4th to 5th Gen Intake Manifold Swap Information
05-21-2001, 05:37 PM
#1
Senior Member
Thread Starter
Join Date: Nov 2000
Posts: 359
- For those of you who have been reading "Don in Texas'" thread on the Exhaust Manifold port and polish work, you'll know that one of the factors limiting a 4th gen's power is its intake manifold. The 5th generation car, which mechanically, is very similar to the 4th, utilizes a dual stage intake manifold. This piece switches to a shorter intake runner length somewhere in the rev range to provide more top-end horsepower. (The 4th gen cars only have a single, long runner that hinders top-end performance.)
- Since the cars are so similar, I'm trying to find out if a 4th gen owner can swap the manifolds and gain some horsepower.
- Also, the main difference between the two generations (***as far as I have been able to determine***) is the intake manifold that we're discussing and that the newer cars use an "equal length something" in their exhaust system. If someone could reply and give me more details, it would definitely help. Other than that, I'm almost positive that everything from the block to the pistons to the cams to the whatever is the same. (Yes, the exhaust manifolds (Part # 14002) and their respective gaskets (Part # 14036M) are the same, so I doubt that they touched the heads or the actual exhaust manifolds. The exhaust changes must be somewhere in the vicinity of the restrictive pre-cat.)
- OK, I called in to my dealership today and got some information. First, the 5th gen intake manifold is $441.34 and the splitter that goes from the intake manifold to the two heads is $528.01 or $578.01 (price depends on something that I didn't quite catch). [If someone knows what the technical name is for the "splitter" please correct me.]
- The few Nissan parts diagrams that I have show that many of the part numbers are identical amongst the two manifolds. The manifold and the splitter and the gaskets may be the only things that we need.
- I wasn't able to determine from the parts guy or the service manager whether the manifold operates electrically (ECU controlled) or if the intake runner change is physical (air flow, etc). My Miata friend said that the new Miatas use an ECU controlled unit for their dual-stage manifolds. Fortunately, he feels that a relay could be hooked up to control the manifold (either a switch in the cabin or a rpm-governed relay). He's heard of people do it with other cars, so he's fairly confident that it will work on us.
- This is all I have so far. I'll be checking in periodically as I gather more information. If you write back, please don't copy all of my threads - they tend to be quite lengthy. Just be descriptive as to what you're replying to.
- Thanks. ;-)
- Since the cars are so similar, I'm trying to find out if a 4th gen owner can swap the manifolds and gain some horsepower.
- Also, the main difference between the two generations (***as far as I have been able to determine***) is the intake manifold that we're discussing and that the newer cars use an "equal length something" in their exhaust system. If someone could reply and give me more details, it would definitely help. Other than that, I'm almost positive that everything from the block to the pistons to the cams to the whatever is the same. (Yes, the exhaust manifolds (Part # 14002) and their respective gaskets (Part # 14036M) are the same, so I doubt that they touched the heads or the actual exhaust manifolds. The exhaust changes must be somewhere in the vicinity of the restrictive pre-cat.)
- OK, I called in to my dealership today and got some information. First, the 5th gen intake manifold is $441.34 and the splitter that goes from the intake manifold to the two heads is $528.01 or $578.01 (price depends on something that I didn't quite catch). [If someone knows what the technical name is for the "splitter" please correct me.]
- The few Nissan parts diagrams that I have show that many of the part numbers are identical amongst the two manifolds. The manifold and the splitter and the gaskets may be the only things that we need.
- I wasn't able to determine from the parts guy or the service manager whether the manifold operates electrically (ECU controlled) or if the intake runner change is physical (air flow, etc). My Miata friend said that the new Miatas use an ECU controlled unit for their dual-stage manifolds. Fortunately, he feels that a relay could be hooked up to control the manifold (either a switch in the cabin or a rpm-governed relay). He's heard of people do it with other cars, so he's fairly confident that it will work on us.
- This is all I have so far. I'll be checking in periodically as I gather more information. If you write back, please don't copy all of my threads - they tend to be quite lengthy. Just be descriptive as to what you're replying to.
- Thanks. ;-)
05-21-2001, 05:52 PM
#2
Sounds like good project...
I'm sure it can be made to work... with a little creativity... that is...
I'm sure a $1000 price tag is too heavy a ticket for the (relatively) few ponies it offers but if the intake parts can be obtained for cheap from junkyards, then it could be a good modification.
Unfortunately, few of us can have our cars down for several weeks to do the fabrication/modifications that are probably needed. We'll leave that to the 'trail blazers' amongst us
who have another vehicle as a primary car.
I'm sure it can be made to work... with a little creativity... that is...
I'm sure a $1000 price tag is too heavy a ticket for the (relatively) few ponies it offers but if the intake parts can be obtained for cheap from junkyards, then it could be a good modification.
Unfortunately, few of us can have our cars down for several weeks to do the fabrication/modifications that are probably needed. We'll leave that to the 'trail blazers' amongst us
who have another vehicle as a primary car.
05-21-2001, 06:29 PM
#3
"For those of you who have been reading "Don in Texas'" thread on the Exhaust Manifold port and polish work, you'll know that one of the factors limiting a 4th gen's power is its intake manifold. "
Thats not what I said. I said that the exhaust manifolds are good as OEM units for the amount of air that can be processed through the engine. I don't think the intake manifolds can be much better. You simply need to push more air through the engine (heads, forced induction, etc.)
Those intakes on the 4th gen are OK, there may be an increase with a different runner design, but I'm not gonna find out
Thats not what I said. I said that the exhaust manifolds are good as OEM units for the amount of air that can be processed through the engine. I don't think the intake manifolds can be much better. You simply need to push more air through the engine (heads, forced induction, etc.)
Those intakes on the 4th gen are OK, there may be an increase with a different runner design, but I'm not gonna find out
05-21-2001, 07:12 PM
#4
Guest
Posts: n/a
Thanks for the info, but it sounds like a recording? I know for a fact we have heard this before already...same info! Oh well....
Also the 5th gen does have different cams than the 4th gen, actually less aggressive....thats about the only internal difference.
Also the 5th gen does have different cams than the 4th gen, actually less aggressive....thats about the only internal difference.
Originally posted by SleeperSE
- For those of you who have been reading "Don in Texas'" thread on the Exhaust Manifold port and polish work, you'll know that one of the factors limiting a 4th gen's power is its intake manifold. The 5th generation car, which mechanically, is very similar to the 4th, utilizes a dual stage intake manifold. This piece switches to a shorter intake runner length somewhere in the rev range to provide more top-end horsepower. (The 4th gen cars only have a single, long runner that hinders top-end performance.)
- Since the cars are so similar, I'm trying to find out if a 4th gen owner can swap the manifolds and gain some horsepower.
- Also, the main difference between the two generations (***as far as I have been able to determine***) is the intake manifold that we're discussing and that the newer cars use an "equal length something" in their exhaust system. If someone could reply and give me more details, it would definitely help. Other than that, I'm almost positive that everything from the block to the pistons to the cams to the whatever is the same. (Yes, the exhaust manifolds (Part # 14002) and their respective gaskets (Part # 14036M) are the same, so I doubt that they touched the heads or the actual exhaust manifolds. The exhaust changes must be somewhere in the vicinity of the restrictive pre-cat.)
- OK, I called in to my dealership today and got some information. First, the 5th gen intake manifold is $441.34 and the splitter that goes from the intake manifold to the two heads is $528.01 or $578.01 (price depends on something that I didn't quite catch). [If someone knows what the technical name is for the "splitter" please correct me.]
- The few Nissan parts diagrams that I have show that many of the part numbers are identical amongst the two manifolds. The manifold and the splitter and the gaskets may be the only things that we need.
- I wasn't able to determine from the parts guy or the service manager whether the manifold operates electrically (ECU controlled) or if the intake runner change is physical (air flow, etc). My Miata friend said that the new Miatas use an ECU controlled unit for their dual-stage manifolds. Fortunately, he feels that a relay could be hooked up to control the manifold (either a switch in the cabin or a rpm-governed relay). He's heard of people do it with other cars, so he's fairly confident that it will work on us.
- This is all I have so far. I'll be checking in periodically as I gather more information. If you write back, please don't copy all of my threads - they tend to be quite lengthy. Just be descriptive as to what you're replying to.
- Thanks. ;-)
- For those of you who have been reading "Don in Texas'" thread on the Exhaust Manifold port and polish work, you'll know that one of the factors limiting a 4th gen's power is its intake manifold. The 5th generation car, which mechanically, is very similar to the 4th, utilizes a dual stage intake manifold. This piece switches to a shorter intake runner length somewhere in the rev range to provide more top-end horsepower. (The 4th gen cars only have a single, long runner that hinders top-end performance.)
- Since the cars are so similar, I'm trying to find out if a 4th gen owner can swap the manifolds and gain some horsepower.
- Also, the main difference between the two generations (***as far as I have been able to determine***) is the intake manifold that we're discussing and that the newer cars use an "equal length something" in their exhaust system. If someone could reply and give me more details, it would definitely help. Other than that, I'm almost positive that everything from the block to the pistons to the cams to the whatever is the same. (Yes, the exhaust manifolds (Part # 14002) and their respective gaskets (Part # 14036M) are the same, so I doubt that they touched the heads or the actual exhaust manifolds. The exhaust changes must be somewhere in the vicinity of the restrictive pre-cat.)
- OK, I called in to my dealership today and got some information. First, the 5th gen intake manifold is $441.34 and the splitter that goes from the intake manifold to the two heads is $528.01 or $578.01 (price depends on something that I didn't quite catch). [If someone knows what the technical name is for the "splitter" please correct me.]
- The few Nissan parts diagrams that I have show that many of the part numbers are identical amongst the two manifolds. The manifold and the splitter and the gaskets may be the only things that we need.
- I wasn't able to determine from the parts guy or the service manager whether the manifold operates electrically (ECU controlled) or if the intake runner change is physical (air flow, etc). My Miata friend said that the new Miatas use an ECU controlled unit for their dual-stage manifolds. Fortunately, he feels that a relay could be hooked up to control the manifold (either a switch in the cabin or a rpm-governed relay). He's heard of people do it with other cars, so he's fairly confident that it will work on us.
- This is all I have so far. I'll be checking in periodically as I gather more information. If you write back, please don't copy all of my threads - they tend to be quite lengthy. Just be descriptive as to what you're replying to.
- Thanks. ;-)
05-21-2001, 08:34 PM
#5
Not DAVEB the parts guy
Join Date: Aug 2000
Posts: 8,555
What I want to know is if the lower intake manifold (splitter) has the same gaskets as the 4th gen. If it does, then to hell with the low 5th gen splitter, I'll just want the top half. The activation of the runner butterflies can easily be done with a rpm swtich.
Vacumn lines, holes, mounting points would have to fabbed so that the 4th gen stuff bolts up to the 5th gen stuff.
Finally, we know the 4th gen VQ can be run to redline safey. My concern is fuel. The additional air of the 5th gen manifold may not be compensated by the 4th gen ECU therefore creating a lean condition and detonation. Anyone else have this concern? I guess a fuel computer (Super AFC) would work if it could supply enough fuel.
I really want to do this, but money is a little tight. It is really a fairly simple concept and I think we could be looking at atleast 20fwhp which is pretty significant if you ask me. 4th gens could easily be in the low low 14s for about $2000 in mods.
Dave
Vacumn lines, holes, mounting points would have to fabbed so that the 4th gen stuff bolts up to the 5th gen stuff.
Finally, we know the 4th gen VQ can be run to redline safey. My concern is fuel. The additional air of the 5th gen manifold may not be compensated by the 4th gen ECU therefore creating a lean condition and detonation. Anyone else have this concern? I guess a fuel computer (Super AFC) would work if it could supply enough fuel.
I really want to do this, but money is a little tight. It is really a fairly simple concept and I think we could be looking at atleast 20fwhp which is pretty significant if you ask me. 4th gens could easily be in the low low 14s for about $2000 in mods.
Dave
05-22-2001, 12:20 AM
#6
Turtle turtle... Moderator
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i think an upper 5th gen manifold to lower pleum(sp) of a 4th gen would be better if it bolts up. Dont forget 5th gen uses top feed injectors while 4th gen uses side feed. if you swapped both upper and lower maniolds from a 5th gen i think the injectors have to be changed as well. something to think about....
05-22-2001, 06:31 AM
#7
Guest
Posts: n/a
Guys, check out www.car-part.com. I called one shop and they have the upper and lower manifold pieces for $75 apiece (used). FYI those are technically the names of the manifold pieces (lower manifold is the "splitter" previously referred to).
Installation will take a LOT of homework prior to starting. Whether or not a lot of the components are compatible between the two gens is in question. Will the throttle body from the 4th gen work? What about the idle control body (with the A/C solenoid, P/S solenoid, etc). What about the throttle cables? Will the fuel injectors/rails work? (I kinda doubt that since the 5th gen uses totally different FIs with top, not side-mounted rails.) You'll most likely need to either get the 5th gen airbox+plumbing because the angle off the TB is different on the 5th gen manifold.
There are a lot of concerns above and beyond whether or not the manifolds themselves will fit, which I have no doubt they will. Most likely it's totally do-able, but like Don said, "somebody needs to just do it and quit talking about it". I do disagree with Don, though...although the 4th gen manifold really isn't all that restrictive from a static flow standpoint (not too rough inside, pretty gentle radiuses, etc), it IS "restrictive" from a pulsed flow/dynamic standpoint. The runners are simply too long to make high rpm power. They're tuned for low/mid-rpm "ramming". The 5th gen manifold is responsible for at MINIMUM 80% of the HP gain on the 5th gen (all gains past 5000 rpm). As Dave said, 20 HP at the wheels is a pretty reasonable estimate, if not conservative, of what kind of gains a 4th gen would see with this manifold. I don't think the air-fuel ratios will be all that outta whack either because our fuel curves are based on AIRFLOW. The increase in airflow will be sensed by the MAF sensor and cause the ECU to run higher injector pulsewidths. The ECU may not be tuned optimally for the 5th gen manifold, but it should work fine.
Oh yeah, another problem with the 5th gen manifold retrofit is the whole issue with how are you going to power the variable volume valve solenoid, but I think most creative people here understand that you can use a rpm-activated switch to do that, so that at least is not too much of an unknown.
Installation will take a LOT of homework prior to starting. Whether or not a lot of the components are compatible between the two gens is in question. Will the throttle body from the 4th gen work? What about the idle control body (with the A/C solenoid, P/S solenoid, etc). What about the throttle cables? Will the fuel injectors/rails work? (I kinda doubt that since the 5th gen uses totally different FIs with top, not side-mounted rails.) You'll most likely need to either get the 5th gen airbox+plumbing because the angle off the TB is different on the 5th gen manifold.
There are a lot of concerns above and beyond whether or not the manifolds themselves will fit, which I have no doubt they will. Most likely it's totally do-able, but like Don said, "somebody needs to just do it and quit talking about it". I do disagree with Don, though...although the 4th gen manifold really isn't all that restrictive from a static flow standpoint (not too rough inside, pretty gentle radiuses, etc), it IS "restrictive" from a pulsed flow/dynamic standpoint. The runners are simply too long to make high rpm power. They're tuned for low/mid-rpm "ramming". The 5th gen manifold is responsible for at MINIMUM 80% of the HP gain on the 5th gen (all gains past 5000 rpm). As Dave said, 20 HP at the wheels is a pretty reasonable estimate, if not conservative, of what kind of gains a 4th gen would see with this manifold. I don't think the air-fuel ratios will be all that outta whack either because our fuel curves are based on AIRFLOW. The increase in airflow will be sensed by the MAF sensor and cause the ECU to run higher injector pulsewidths. The ECU may not be tuned optimally for the 5th gen manifold, but it should work fine.
Oh yeah, another problem with the 5th gen manifold retrofit is the whole issue with how are you going to power the variable volume valve solenoid, but I think most creative people here understand that you can use a rpm-activated switch to do that, so that at least is not too much of an unknown.
05-22-2001, 06:45 AM
#8
Senior Member
Join Date: Jan 2001
Posts: 442
food for thought
This thread is trying to compare the 4th gen's "lack" of high end RPM HP with the 5th gen's ability to compensate. Most seem to think this is the "only" difference between the motors with the exception less agressive cam design. While all this discussion is geared around the difference in HP, has anyone thought about the 4th gen tourque curve vs the 5th gen tourque plateau?
05-22-2001, 10:53 AM
#9
Guest
Posts: n/a
Re: food for thought
Originally posted by Frezny
While all this discussion is geared around the difference in HP, has anyone thought about the 4th gen tourque curve vs the 5th gen tourque plateau?
While all this discussion is geared around the difference in HP, has anyone thought about the 4th gen tourque curve vs the 5th gen tourque plateau?
05-22-2001, 11:10 AM
#10
Senior Member
Join Date: Jan 2001
Posts: 442
Re: Re: food for thought
Originally posted by Keven97SE
Well, in this case torque and HP are kind of one-in-the-same. Increased HP 5000+ rpm plus with the 5th gen intake manifold implies more torque 5000+ rpm. One thing I've noticed is that while the 5th gen torque peak may not be quite as large on the 5th gen, the torque curve is actually broader and smoother, INCLUDING lower rpms. There aren't any nasty "holes" in the torque curve on a 5th gen like on the 4th gen. ...
Well, in this case torque and HP are kind of one-in-the-same. Increased HP 5000+ rpm plus with the 5th gen intake manifold implies more torque 5000+ rpm. One thing I've noticed is that while the 5th gen torque peak may not be quite as large on the 5th gen, the torque curve is actually broader and smoother, INCLUDING lower rpms. There aren't any nasty "holes" in the torque curve on a 5th gen like on the 4th gen. ...
If the rumor of less aggressive cams is true, I'm interested in reasoning behind it. There has got to be some quanititave equation of modifications that can be done to the 4th gen that gives it both the HP and Torque of the 5th gen. Anybody have an "in" with Nissan's engineers?
05-22-2001, 11:37 AM
#11
Re: Re: food for thought
Originally posted by Keven97SE
and cams (actually milder is the information I've gotten, but this is unsubstantiated hearsay, I must admit).
and cams (actually milder is the information I've gotten, but this is unsubstantiated hearsay, I must admit).
Perhaps the engine management is also upgraded in some way? But the intake is the prize winner.
05-22-2001, 11:38 AM
#12
Turtle turtle... Moderator
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id be willing to try this out if i can find them used somewhere cheap. My car will be down for a week when we do the motor/tranny change anyways plus i got my bike back now so i can ride.
05-22-2001, 12:53 PM
#13
Senior Member
Join Date: Jan 2001
Posts: 442
all the power to you
Originally posted by Turbo95Max
id be willing to try this out if i can find them used somewhere cheap. My car will be down for a week when we do the motor/tranny change anyways plus i got my bike back now so i can ride.
id be willing to try this out if i can find them used somewhere cheap. My car will be down for a week when we do the motor/tranny change anyways plus i got my bike back now so i can ride.
05-22-2001, 01:11 PM
#15
Guest
Posts: n/a
Turbo95Max,
I've sent you a private message regarding my source for the 2000 manifolds. I misspoke earlier...the price is actually only $35 apiece! ($70 total) This would definitely be a cool project.
Later,
Keven
I've sent you a private message regarding my source for the 2000 manifolds. I misspoke earlier...the price is actually only $35 apiece! ($70 total) This would definitely be a cool project.
Later,
Keven
Originally posted by Turbo95Max
id be willing to try this out if i can find them used somewhere cheap. My car will be down for a week when we do the motor/tranny change anyways plus i got my bike back now so i can ride.
id be willing to try this out if i can find them used somewhere cheap. My car will be down for a week when we do the motor/tranny change anyways plus i got my bike back now so i can ride.
05-22-2001, 01:32 PM
#16
Originally posted by Keven97SE
Turbo95Max,
I've sent you a private message regarding my source for the 2000 manifolds. I misspoke earlier...the price is actually only $35 apiece! ($70 total) This would definitely be a cool project.
Later,
Keven
Turbo95Max,
I've sent you a private message regarding my source for the 2000 manifolds. I misspoke earlier...the price is actually only $35 apiece! ($70 total) This would definitely be a cool project.
Later,
Keven
05-22-2001, 02:43 PM
#19
Senior Member
Join Date: Sep 2000
Location: NJ
Posts: 5,630
Originally posted by Keven97SE
Check your private messages!
Check your private messages!
05-23-2001, 02:27 AM
#20
Keven I also am interested in this email me I have alot of time on my hnds now that I have been laid off... 
(Regional IT Manager)
One more thing is the CA/NLEV intake different from the Fed version on the 5th gen manifold?
(Regional IT Manager)One more thing is the CA/NLEV intake different from the Fed version on the 5th gen manifold?
05-25-2001, 06:19 AM
#24
Senior Member
Join Date: Aug 2000
Posts: 6,243
Re: Re: Darnit
Originally posted by Murphy_TX_Mike
I did. I will keep you all posted. It may take me a little while to do it. All I have is a WSP Ypipe and Dons VB upgrade. I need to put the car on a dyno to get a base line run.
I live in Dallas. Anybody interested in helping?
Mike
I did. I will keep you all posted. It may take me a little while to do it. All I have is a WSP Ypipe and Dons VB upgrade. I need to put the car on a dyno to get a base line run.
I live in Dallas. Anybody interested in helping?
Mike
I will help
05-27-2001, 07:08 PM
#29
Senior Member
Thread Starter
Join Date: Nov 2000
Posts: 359
Some News
- Hey guys, I am so sorry that I haven't written yet. I honestly haven't been on the web since I started the post (you know how it is sometimes).
- Anyhow, I asked a few questions at my dealership. While there are no performance oriented mechanics/engineers working there, I did get some information...
- First off, the part numbers that I gave out are only half of the real number. The first five digits that I supplied are the "series number" while the later five digits are the final combination. So I can't go by what the parts diagrams that the dealer in Tally gave me.
- Concerning the California/Fed cars: The only time that there was a discrepancy was for 4th gen cars or 1999 model year cars. The 4th gen CA and '99 cars used the same restrictive manifold. The 5th gens all use the same manifold. I'm not sure, but it looks like the 5th gens use the same manifold as the CA and '99 cars I just mentioned. I'll check on this by Tuesday/Wednesday.
- TORQUE PEAK vs. TORQUE PLATEU: This is beginning to make more sense now. Keeping in mind that the VQ has a small stroke (good for revs) and that breathing is unrestricted, it makes sense that they used a "cooler" cam design for the 5th gens. As mentioned before, the lower cam combined with better high-rpm breathing (via the new manifold and better exhaust design) could cause better low rpm pull and a smoother power delivery throughout the rev range - which is also why they can only pull 500 rpm higher, yet still gain 32 horses. Anyone who's driven a 4th gen realizes that there's a bit of a kick right around 3k when then the engine wakes up for about 2 grand.
- THE SWAP!!! The moment you've all been waiting for and will, unfortunately, be disappointed in...
The mechanics and my trusted parts guy both mentioned that something was changed in the 5th gen design, either spark plugs or fuel injectors. The new location of these items could get in the way.
- Frankly, I don't see how this is possible. As far as I can tell (please note that I am unsure of this...) the block and heads were, for the most part, unchanged. Yes, according to a few people, a new cam was used, and every brochure will brag about the "molybdenum" coating in the block - but other than that, Nissan only swapped the intake manifold and created a freer-flowing "equal-length" exhaust (aka - a new, less restrictive y-pipe and a multi-flow muffler).
- Oh, by the way, they referred to the upper section as the intake plenum and the lower as the actual manifold.
- Anyhow, I think that there is a 45% chance that this can be done. With Ken's post that the parts will only be $70, I am HIGHLY interested. Anyone who does this will need the: new plenum and manifold, gaskets, rpm-activated switch, and some patience. Remember those parts diagrams that I mentioned before? Well, even though they are probably off, there are a lot of extra pieces noted on the intake manifold (the lower section).
- I think that with a full exhaust (y-pipe to muffler), the stock 4th gen cam, and the new manifold, one could be looking at about 230hp at the flywheel. I imagine that if the intake plenum were extrude honed and polished, 7 additional hp could be gained. This is more in line with what a VQ should be able to do. Perhaps we should talk to Stillen or Cattman about doing some research?
- Anyhow, let's continue to keep each other posted on this topic. I'll have some specific parts numbers by early next week. See you guys.
Matt
- Anyhow, I asked a few questions at my dealership. While there are no performance oriented mechanics/engineers working there, I did get some information...
- First off, the part numbers that I gave out are only half of the real number. The first five digits that I supplied are the "series number" while the later five digits are the final combination. So I can't go by what the parts diagrams that the dealer in Tally gave me.
- Concerning the California/Fed cars: The only time that there was a discrepancy was for 4th gen cars or 1999 model year cars. The 4th gen CA and '99 cars used the same restrictive manifold. The 5th gens all use the same manifold. I'm not sure, but it looks like the 5th gens use the same manifold as the CA and '99 cars I just mentioned. I'll check on this by Tuesday/Wednesday.
- TORQUE PEAK vs. TORQUE PLATEU: This is beginning to make more sense now. Keeping in mind that the VQ has a small stroke (good for revs) and that breathing is unrestricted, it makes sense that they used a "cooler" cam design for the 5th gens. As mentioned before, the lower cam combined with better high-rpm breathing (via the new manifold and better exhaust design) could cause better low rpm pull and a smoother power delivery throughout the rev range - which is also why they can only pull 500 rpm higher, yet still gain 32 horses. Anyone who's driven a 4th gen realizes that there's a bit of a kick right around 3k when then the engine wakes up for about 2 grand.
- THE SWAP!!! The moment you've all been waiting for and will, unfortunately, be disappointed in...
The mechanics and my trusted parts guy both mentioned that something was changed in the 5th gen design, either spark plugs or fuel injectors. The new location of these items could get in the way.
- Frankly, I don't see how this is possible. As far as I can tell (please note that I am unsure of this...) the block and heads were, for the most part, unchanged. Yes, according to a few people, a new cam was used, and every brochure will brag about the "molybdenum" coating in the block - but other than that, Nissan only swapped the intake manifold and created a freer-flowing "equal-length" exhaust (aka - a new, less restrictive y-pipe and a multi-flow muffler).
- Oh, by the way, they referred to the upper section as the intake plenum and the lower as the actual manifold.
- Anyhow, I think that there is a 45% chance that this can be done. With Ken's post that the parts will only be $70, I am HIGHLY interested. Anyone who does this will need the: new plenum and manifold, gaskets, rpm-activated switch, and some patience. Remember those parts diagrams that I mentioned before? Well, even though they are probably off, there are a lot of extra pieces noted on the intake manifold (the lower section).
- I think that with a full exhaust (y-pipe to muffler), the stock 4th gen cam, and the new manifold, one could be looking at about 230hp at the flywheel. I imagine that if the intake plenum were extrude honed and polished, 7 additional hp could be gained. This is more in line with what a VQ should be able to do. Perhaps we should talk to Stillen or Cattman about doing some research?
- Anyhow, let's continue to keep each other posted on this topic. I'll have some specific parts numbers by early next week. See you guys.
Matt
05-28-2001, 10:41 AM
#30
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Posts: n/a
Re: Some News
That is some good research. Good work man. I do know that JWT did this swap basically when the 5th gen came out back in the day, and it was successful. I don't know what they went through to do it though, but it's defintely possible.
Originally posted by SleeperSE
- Hey guys, I am so sorry that I haven't written yet. I honestly haven't been on the web since I started the post (you know how it is sometimes).
- Anyhow, I asked a few questions at my dealership. While there are no performance oriented mechanics/engineers working there, I did get some information...
- First off, the part numbers that I gave out are only half of the real number. The first five digits that I supplied are the "series number" while the later five digits are the final combination. So I can't go by what the parts diagrams that the dealer in Tally gave me.
- Concerning the California/Fed cars: The only time that there was a discrepancy was for 4th gen cars or 1999 model year cars. The 4th gen CA and '99 cars used the same restrictive manifold. The 5th gens all use the same manifold. I'm not sure, but it looks like the 5th gens use the same manifold as the CA and '99 cars I just mentioned. I'll check on this by Tuesday/Wednesday.
- TORQUE PEAK vs. TORQUE PLATEU: This is beginning to make more sense now. Keeping in mind that the VQ has a small stroke (good for revs) and that breathing is unrestricted, it makes sense that they used a "cooler" cam design for the 5th gens. As mentioned before, the lower cam combined with better high-rpm breathing (via the new manifold and better exhaust design) could cause better low rpm pull and a smoother power delivery throughout the rev range - which is also why they can only pull 500 rpm higher, yet still gain 32 horses. Anyone who's driven a 4th gen realizes that there's a bit of a kick right around 3k when then the engine wakes up for about 2 grand.
- THE SWAP!!! The moment you've all been waiting for and will, unfortunately, be disappointed in...
The mechanics and my trusted parts guy both mentioned that something was changed in the 5th gen design, either spark plugs or fuel injectors. The new location of these items could get in the way.
- Frankly, I don't see how this is possible. As far as I can tell (please note that I am unsure of this...) the block and heads were, for the most part, unchanged. Yes, according to a few people, a new cam was used, and every brochure will brag about the "molybdenum" coating in the block - but other than that, Nissan only swapped the intake manifold and created a freer-flowing "equal-length" exhaust (aka - a new, less restrictive y-pipe and a multi-flow muffler).
- Oh, by the way, they referred to the upper section as the intake plenum and the lower as the actual manifold.
- Anyhow, I think that there is a 45% chance that this can be done. With Ken's post that the parts will only be $70, I am HIGHLY interested. Anyone who does this will need the: new plenum and manifold, gaskets, rpm-activated switch, and some patience. Remember those parts diagrams that I mentioned before? Well, even though they are probably off, there are a lot of extra pieces noted on the intake manifold (the lower section).
- I think that with a full exhaust (y-pipe to muffler), the stock 4th gen cam, and the new manifold, one could be looking at about 230hp at the flywheel. I imagine that if the intake plenum were extrude honed and polished, 7 additional hp could be gained. This is more in line with what a VQ should be able to do. Perhaps we should talk to Stillen or Cattman about doing some research?
- Anyhow, let's continue to keep each other posted on this topic. I'll have some specific parts numbers by early next week. See you guys.
Matt
- Hey guys, I am so sorry that I haven't written yet. I honestly haven't been on the web since I started the post (you know how it is sometimes).
- Anyhow, I asked a few questions at my dealership. While there are no performance oriented mechanics/engineers working there, I did get some information...
- First off, the part numbers that I gave out are only half of the real number. The first five digits that I supplied are the "series number" while the later five digits are the final combination. So I can't go by what the parts diagrams that the dealer in Tally gave me.
- Concerning the California/Fed cars: The only time that there was a discrepancy was for 4th gen cars or 1999 model year cars. The 4th gen CA and '99 cars used the same restrictive manifold. The 5th gens all use the same manifold. I'm not sure, but it looks like the 5th gens use the same manifold as the CA and '99 cars I just mentioned. I'll check on this by Tuesday/Wednesday.
- TORQUE PEAK vs. TORQUE PLATEU: This is beginning to make more sense now. Keeping in mind that the VQ has a small stroke (good for revs) and that breathing is unrestricted, it makes sense that they used a "cooler" cam design for the 5th gens. As mentioned before, the lower cam combined with better high-rpm breathing (via the new manifold and better exhaust design) could cause better low rpm pull and a smoother power delivery throughout the rev range - which is also why they can only pull 500 rpm higher, yet still gain 32 horses. Anyone who's driven a 4th gen realizes that there's a bit of a kick right around 3k when then the engine wakes up for about 2 grand.
- THE SWAP!!! The moment you've all been waiting for and will, unfortunately, be disappointed in...
The mechanics and my trusted parts guy both mentioned that something was changed in the 5th gen design, either spark plugs or fuel injectors. The new location of these items could get in the way.
- Frankly, I don't see how this is possible. As far as I can tell (please note that I am unsure of this...) the block and heads were, for the most part, unchanged. Yes, according to a few people, a new cam was used, and every brochure will brag about the "molybdenum" coating in the block - but other than that, Nissan only swapped the intake manifold and created a freer-flowing "equal-length" exhaust (aka - a new, less restrictive y-pipe and a multi-flow muffler).
- Oh, by the way, they referred to the upper section as the intake plenum and the lower as the actual manifold.
- Anyhow, I think that there is a 45% chance that this can be done. With Ken's post that the parts will only be $70, I am HIGHLY interested. Anyone who does this will need the: new plenum and manifold, gaskets, rpm-activated switch, and some patience. Remember those parts diagrams that I mentioned before? Well, even though they are probably off, there are a lot of extra pieces noted on the intake manifold (the lower section).
- I think that with a full exhaust (y-pipe to muffler), the stock 4th gen cam, and the new manifold, one could be looking at about 230hp at the flywheel. I imagine that if the intake plenum were extrude honed and polished, 7 additional hp could be gained. This is more in line with what a VQ should be able to do. Perhaps we should talk to Stillen or Cattman about doing some research?
- Anyhow, let's continue to keep each other posted on this topic. I'll have some specific parts numbers by early next week. See you guys.
Matt
05-28-2001, 04:51 PM
#31
Senior Member
Thread Starter
Join Date: Nov 2000
Posts: 359
Re: Re: Some News
Originally posted by RussMaxManiac
That is some good research. Good work man. I do know that JWT did this swap basically when the 5th gen came out back in the day, and it was successful. I don't know what they went through to do it though, but it's defintely possible.
That is some good research. Good work man. I do know that JWT did this swap basically when the 5th gen came out back in the day, and it was successful. I don't know what they went through to do it though, but it's defintely possible.
- That's great news, man. I'm going to go e-mail JWT right now to see what I can find out.
- Also, if anyone has dyno charts of the following, please post:
1. Stock 4th gen
2. 4th gen w/ Y-pipe
3. 4th gen w/ Y-pipe and full exhaust (please note if the cat is stock or aftermarket)
4. Stock 5th gen
5. 5th gen w/ Y-pipe
6. 5th gen w/ Y-pipe and full exhaust (please note if the cat is stock or aftermarket)
7. 4th or 5th gen car with any work done to intake manifold or plenum (ie, port and polish work or extrude hone work)
- I will have the specific part numbers either tomorrow or Wednesday. Catch you guys then.
Matt
05-31-2001, 04:35 PM
#32
Senior Member
Thread Starter
Join Date: Nov 2000
Posts: 359
Great News!!!
- OK, I got the part numbers yesterday. It turns out that even the 5th generation cars have discrepancies amongst them. The throttle body and the intake plenum are different between the 2000 and 2001 vehicles. Everything else that I checked was identical within the generation.
- The great news is that the gasket that connects the manifold to the heads (14035-38U00) is the same from 4th to 5th generation cars. This means that if we can get the stuff above the heads to fit, no physical modifications to the heads will be necessary.
- Now, the part that switches the intake runners is actually the intake plenum, not the manifold. Obviously, it would be a snap if all you had to do was swap plenums. Unfortunately, looking at the gaskets that fit between the plenum and the manifold (4th gen: 14032-38U00, 5th gen: 14033-2Y900), the parts won’t match up. This means that if you want the dual-stage intake plenum, then you need to swap the manifold too.
- OK, so now we’ve swapped the manifold and the plenum, but it looks like the stock throttle body won’t fit. You have to pop a 5th gen throttle body into place in order to fit the plenum. (2000 model year throttle body: 16119-2Y900, 2001 model year throttle body: 16119-4Y900.) Also, there are TWO, not one gaskets that connect the newer throttle bodies to the plenum. The two gaskets sandwich a new “bracket/collector/thingamajig” that goes between the throttle body and the plenum. The part number for the two gaskets (they’re the same gasket, just buy two of them) is: 16175-2Y900. The part number for the bracket/collector thing is: 14040-2Y900.
- After you buy all these parts and gaskets, you shouldn’t have a problem bolting things into place. The new throttle body should pop in and you should (I’m not sure) be able to fit the original 4th gen throttle body sleeve around it. Then, you’ll need to hook up an rpm-activated switch for the plenum to actually swap intake runners. I have no clue how to do that, nor do I know what rpm to recommend (I imagine that it would be around 4500rpm). If someone could get information on how to hook up an rpm-switch and find out at what rpm the 5th gens swap runners, it would be appreciated.
- (Just looking at the Nissan diagrams, which the entire Parts Department at my dealership says are not very accurate, there are a few extra nuts and bolts that connect the plenum to the manifold. So, just be prepared to buy a few of those too.)
- One last thing, you should buy a Haynes Manual so that you’ll know what order the bolts should be loosened and tightened on the manifold, heads, and plenum. It won’t make as much sense if someone just posts it – go buy the book and study the diagram. Also, every time you take a part off, you’ll need to use a new gasket. Don’t get lazy! This is your engine – buy the new gaskets and make sure that they fit snugly.
- OK, we just need to find out about the electrical switch and the rpm the runner should swap at. I think that this really could work. The only thing that I'm worried about is that the throttle cables might get in the way. I'm sure that, when performing the swap, it would be very helpful to have some pictures of your engine bay and a 5th gen car next to you for reference.
- Matt
- The great news is that the gasket that connects the manifold to the heads (14035-38U00) is the same from 4th to 5th generation cars. This means that if we can get the stuff above the heads to fit, no physical modifications to the heads will be necessary.
- Now, the part that switches the intake runners is actually the intake plenum, not the manifold. Obviously, it would be a snap if all you had to do was swap plenums. Unfortunately, looking at the gaskets that fit between the plenum and the manifold (4th gen: 14032-38U00, 5th gen: 14033-2Y900), the parts won’t match up. This means that if you want the dual-stage intake plenum, then you need to swap the manifold too.
- OK, so now we’ve swapped the manifold and the plenum, but it looks like the stock throttle body won’t fit. You have to pop a 5th gen throttle body into place in order to fit the plenum. (2000 model year throttle body: 16119-2Y900, 2001 model year throttle body: 16119-4Y900.) Also, there are TWO, not one gaskets that connect the newer throttle bodies to the plenum. The two gaskets sandwich a new “bracket/collector/thingamajig” that goes between the throttle body and the plenum. The part number for the two gaskets (they’re the same gasket, just buy two of them) is: 16175-2Y900. The part number for the bracket/collector thing is: 14040-2Y900.
- After you buy all these parts and gaskets, you shouldn’t have a problem bolting things into place. The new throttle body should pop in and you should (I’m not sure) be able to fit the original 4th gen throttle body sleeve around it. Then, you’ll need to hook up an rpm-activated switch for the plenum to actually swap intake runners. I have no clue how to do that, nor do I know what rpm to recommend (I imagine that it would be around 4500rpm). If someone could get information on how to hook up an rpm-switch and find out at what rpm the 5th gens swap runners, it would be appreciated.
- (Just looking at the Nissan diagrams, which the entire Parts Department at my dealership says are not very accurate, there are a few extra nuts and bolts that connect the plenum to the manifold. So, just be prepared to buy a few of those too.)
- One last thing, you should buy a Haynes Manual so that you’ll know what order the bolts should be loosened and tightened on the manifold, heads, and plenum. It won’t make as much sense if someone just posts it – go buy the book and study the diagram. Also, every time you take a part off, you’ll need to use a new gasket. Don’t get lazy! This is your engine – buy the new gaskets and make sure that they fit snugly.
- OK, we just need to find out about the electrical switch and the rpm the runner should swap at. I think that this really could work. The only thing that I'm worried about is that the throttle cables might get in the way. I'm sure that, when performing the swap, it would be very helpful to have some pictures of your engine bay and a 5th gen car next to you for reference.
- Matt
05-31-2001, 06:31 PM
#33
Senior Member
Join Date: Oct 2000
Posts: 172
This sounds great, but has anyone actually tried porting the original setup ? If we could squeeze a simular amount of power just by porting the intake and exhaust manifolds without having to buy new parts surely this would be a more cost effective solution.
06-01-2001, 05:49 AM
#34
Senior Member
Join Date: Jan 2001
Posts: 442
Originally posted by MR_Maxi
If we could squeeze a simular amount of power just by porting the intake and exhaust manifolds without having to buy new parts surely this would be a more cost effective solution.
If we could squeeze a simular amount of power just by porting the intake and exhaust manifolds without having to buy new parts surely this would be a more cost effective solution.
06-01-2001, 05:58 AM
#35
Originally posted by Frezny
Porting is not the direction to go in this case.
Porting is not the direction to go in this case.
06-01-2001, 06:09 AM
#36
Senior Member
Join Date: Jan 2001
Posts: 442
Originally posted by Blade_99SE
Actually porting and polishing the intake head along with extrude honing the upper and lower intake manifolds will help....
Actually porting and polishing the intake head along with extrude honing the upper and lower intake manifolds will help....
Keven97SE were comparing dyno graphs and he noticed that the toque started falling off on my car about 500rpms sooner and faster on my cars {the 95SE & 99SE} than on his 97SE. He also dosen't have his intake heads ported.
06-01-2001, 06:16 AM
#37
There is no way porting will yeild the expected gains of a manifold swap. With a manifold swap you can expect 12-20 hp increase at the crank. Basicly we expect the dyno graph to keep going up instead of falling off at 5500rpm. And as was stated by Don. Porting the exhaust did nothing.
ZuM
ZuM
Originally posted by MR_Maxi
This sounds great, but has anyone actually tried porting the original setup ? If we could squeeze a simular amount of power just by porting the intake and exhaust manifolds without having to buy new parts surely this would be a more cost effective solution.
This sounds great, but has anyone actually tried porting the original setup ? If we could squeeze a simular amount of power just by porting the intake and exhaust manifolds without having to buy new parts surely this would be a more cost effective solution.
06-01-2001, 07:45 AM
#38
Originally posted by Frezny
If he doesn't have them ported, then what are you camparing here? None of our cars are identical. There will be discrepensies. (SP?) What mods are you running and what has he done to his car. This will affect the curve as well.
If he doesn't have them ported, then what are you camparing here? None of our cars are identical. There will be discrepensies. (SP?) What mods are you running and what has he done to his car. This will affect the curve as well.
I was just stating that porting the heads on the intake side to match the extruding honing will possibly increase power more than just extrude honning alone.
I believe that are power mods were about the same, Cai, y-pipe, cat, custom b-pipe, and muffler. The thing is if you examine the torque curve on a BPU modded max the torque will look similar, TQ spikes at 2400, 3600, ~4800, with power dropping of at 5000 or so. One Kevens his TQ doesn't start falling untill ~5500.
I wan't saying that porting and extrude honnig will work as well as a 5th gen manifold swap, but It will work.
06-01-2001, 08:28 AM
#39
Originally posted by ZuMBLe
There is no way porting will yeild the expected gains of a manifold swap. With a manifold swap you can expect 12-20 hp increase at the crank. Basicly we expect the dyno graph to keep going up instead of falling off at 5500rpm. And as was stated by Don. Porting the exhaust did nothing.
ZuM
There is no way porting will yeild the expected gains of a manifold swap. With a manifold swap you can expect 12-20 hp increase at the crank. Basicly we expect the dyno graph to keep going up instead of falling off at 5500rpm. And as was stated by Don. Porting the exhaust did nothing.
ZuM
Let see what changes were made between 5th gen and 4th gen engines.
1) larger air box and different intake system. This difference can be negated by a CAI or other intake system.
2) Different intake manifold and TB.
3) Slightly less agressive exhaust cam. From what I've read on the board this doesn't make a difference.
4) Supposedly refinished internal to reduce friction. I'm not sure what they have done.
5) The ecu has been retuned.
6) Reworked Y-pipe. This can be negated by and aftermarket y-pipe
7) Last and Least is the muffler. No biggie. I actual have one. It made me lose power until I installed a y-pipe.
8) Different fuel system.
All these things {plus I'm sure stuff I missed} are why the 5th gen makes an extra 32 hp and 12 TQ.
Question I how much power does a 5th gen make with a CAI, Y-pipe, and exhaust? I think is about 195 - 205 at the wheels.
Most 4th gens with a y-pipe, CAI, and exhaust make 175-185 at the wheels.
Well after look at all this it just might produce an 10 hp at the wheels. Oh well never mind.
I hope this works out.
06-01-2001, 11:57 AM
#40
Senior Member
Join Date: Jan 2001
Posts: 442
Originally posted by Blade_99SE
...One Kevens his TQ doesn't start falling untill ~5500.
...One Kevens his TQ doesn't start falling untill ~5500.
I wan't saying that porting and extrude honnig will work as well as a 5th gen manifold swap, but It will work.