That's only if you don't have any other mods to compensate for the slight drop in HP in the lower rpm's.

 

Any mods that would increase power in the lower RPM would be an improvement for either manifold.

For example - If you where to add a Y pipe to a USIM max and a MEVI max they would both see the same increase through the powerband so the USIM would always be ahead in the lower RPM ranges (and the MEVI in the upper RPM ranges). So A Y pipe might bring the MEVI up to USIM levels in the lower RPM ranges but it would also improve a USIM Max in the lower RPM range giving the USIM Max approximatly the same advantage it had before the Y-pipe was added.

Edit - Unless you know of a mod that will show gains the MEVI Max but not for the USIM Max.

 

Don't mind you linking at all.

I haven't studied the 4th gen VI dynos much until looking at these.

I am surprised. On the 5th gen, the dyno plot below 5500 is EXACTLY the same regardless of whether the vias is enabled or disabled (excluding variations from one dyno day to another as in the one of mine to which you linked).

On the 4th gen, that doesn't seem to be the case - the mevi seems to be lower throughout until 6000 or so. Perhaps that is why nissan moved to the composite intake manifold despite its obvious repair limitations.

From that, I tend to agree with you.

One dyno I've never done but wished I had several times is one with the vias set on the shorter intake runners the whole time instead of just at 5500 rpms.

 

I take it from the last post that the VIM on the 5th gen is activated at approximately 5500rpm as well? The reason the 5th gen VIM is superior in all RPM ranges is it's true dual runner design. The MEVI does not have 2 sets of runners, the opening of the secondary plenum effectively shortens the length of the runners, but not effectively as short as the 5th gen short runners, hence even more high RPM power from the 5th gen VIM. At low RPM, the MEVI in the closed position functions as a set of long runners, increasing low and midrange torque. But they aren't as "long" as the 5th gen long runners are, hence more low end grunt from the 5th gen than an MEVI 4th gen.

These are the differences in a nutshell.

 

I am almost positive that the VI on the 5th gen opens at 5000 RPM. If you look at Max_Gators dyno VI vs. no VI the VI power begins to build at 5000 RPM and by 5500 RPM the diffence is already 20 HP.

I agree with you that the 5th gen intake is better because it is a true dual runner design. My guess on the reason for the MEVI low end power loss is that the butterflys for the secondary plenum somehow cause turbulance or restriction in the intake runner.

I wonder if the long runners on the 5th Gen intake are longer than the runners on th 4th gen USIM and that gives it some of the low end power advantage?

 

what are the major hurdles to doing this?

Has it been attempted and failed?

Thanks in advance!

 

You can't fit the 5th gen IM under a 4th gen hood, that's a major one.

 

I believe this is correct. It seems to be taller. The TB is in a different location also, but that is not such a big deal.

 

Hood height is not a problem. Even though the plenum is taller, it should still fit at least with slight rubbing. If the 5th gen strut bar will fit, which it will, then the plenum should still fit underneath. I've got a 5th gen strut bar on my 4th gen, and it rubs slightly despite the fact it appears to be about an inch too tall.

David

 

5th gens open at 5000 not 5500. I transposed the number.

 

isnt a carbon fiber hood higher because its thinner or i would be willing to cut the webbing under the hood. Too bad sombody like cattman,jim wolf doesnt see the potential of this.I would put down 700 or 800 dollers for this setup.

 

The CF hood has much more room, probably on the order of 1.5 inches because there is no supporting structure or heat sheilding at the area where the manifold is.

 

The fuel injectors and fuel rail are the same, right?

The TB position shouldn't be that difficult to change, since it's just cables.

Is there something else, because if hood clearance is the biggest issue, I'd go with a COWL hood to clear. The 5th gen VIAS is controlled via vacuum and an ECU signal at 5K rpms, so with a Harlan switch or custom JWT ECU w/output signal, it should be possible.

4th gens. light weight + VIAS + JWT 7000-7200rpm ECU

 

 

Nope, the 5th gen uses totally different fuel injectors and fuel rail than the 4th gen...top feed instead of side feed. Don't know if the 4th gen injectors can be used on a 5th gen manifold, don't know if the 5th gen injectors can be used with the 4th gen connectors. Also different on the 5th gen manifold: idle air assembly is completely different (idle valve, A/C comensation valve, P/S compensation valve), canister purge control valve is different, EGR connection is different, throttle body is different.

Heck, just about EVERYTHING that bolts up to the intake manifold is different between the 4th and 5th gens. Whether or not the 5th gen manifold physically fits the 4th gen is only one and a relatively minor detail.

 

That makes more sense. I knew it couldn't have been simply hood clearance.

 

Yep, I saw this two years ago when I compared Russ' 01 SE to my 96 SE. Everyone told me I was full of crap and the 5th manifold would work on the 4th gen

As for hood clearance, the 5th gen manifold would most definately rub the 4th gen hood and when you factor in how much the VQ moves up and down in it's mounts, you're going to have a hood that looks like it's breathing...up and down.



Dave

 

I keep reading this over and over. I dont see ANY of those things as being a problem?
First thing use the entire engine , but swap all 4 gen electronics that can be done. Use all the 4 gen valves and egr parts for 5 gen manifold.( I have access to aircraft grade epoxy resin and plastic reinforced composites.) Solution cutoff the hookups on the 4 gen intake manifold ,then epoxy these things to 5 gen manifold . Then direct hookups!. Also some of those things arent even needed.
I probably wouldnt switch some things ,actually most things A/C compensation valve?I dont understand the big problem with this?
Hood problem carbon fiber for clearence ,also really good motor mounts to keep engine from moving and last hammer for firewall if needed
To me the pathfinder TB on my car was quite easy. Im sure if i worried about the cold idle valve on the TB i would have not done it. So it was totaly deleted and to my amazement i could tell no difference between having and not having it.
If you have anything you would like to add or flame feel free. And if you have helpful knowledge thats even better.

 

Dont 99-01's have the aggresive cams. But anyways, witch 5th Gen are you guys talking bout, 00-01, or 02-03>??!?!?!

I know the 00's almost the same manifold, its just heat coated or something

 

they are comparing the vq30de (95-99) to the v30de-k (00-01)

the 02-03's have a different engine (vq35de).. and its a whole other story trying to get things from that engine onto a 4th gen

 

When I made my custom intake I asked my airplane mechanic uncle for some of his stuff. Basically the stuff is retarded, it got so HOT so quickly, But it stayed in place, I was amased it didnt melt and go in My engine

 

This was all before the whole MEVI discovery....

 

die thread die

 

Why waste your time with the 5th gen inatke mainfold when 4th gens has the proven MEVI intake mainfold.

Just my .02 cents
Eric

 

You obviously don't know the difference between the MEVI and the 5th gen manifold. If you did you would've known that posting that will just start another fight.

 

Maybe the fact that a 5th gen intake manifold would be much easier to find, and possibly cheaper than an MEVI..

 

not only that, although mevi works very similar to the 5th gen builtin mevi, i heard the horsepower curve was still a little different, like the 5th gen curve was a little smoother...they have a short and long head osmething something? i dont know the terminology but i think the 5th gen VI setup is still better than the 4th gen japanese VI. Something i read proved this but i forgot where...

for the little hp difference from USVI and 5th gen VI, i dont think its worth checking out anyway....

 

Im not looking at a few measly ponies ,im looking at where they are. Doesnt the 2000 have peak HP around redline . With aftermarket cams i can see the sweet 8000rpm.

 

wow someone sure dug deep here

FYI, the 5th gen VIAS manifold is actuated mechanically (it contains butterfly valves inside the manifold which switch between the two runners), but the mechanical actuation is done by a vacuum diaphragm (Power Valve), who receives its vacuum signal inside some cast assembly on the plenum where it's bolted to... basically there's a vacuum tank on the driver-side end of the plenum, which has an internal route to the Power Valve, but there's also a fresh-air vent to the Power Valve, and the VIAS Control Solenoid switches the Power Valve between those two sources (vacuum vs. fresh-air). The whole assembly looks like one big molded thing (Power Valve, vacuum tank, VIAS and Swirl Control [unrelated] solenoid/vacuum routing box, with all vacuum & fresh-air routes implemented inside) This VIAS Control Solenoid can be activated by any +12V signal to my knowledge, so a simple RPM switch can be used to actuate it. In fact, I've considered toying with that for ****s & giggles... (changing my 2K's VIAS opening parameters to see what happens if I open it at, say, 4000 instead)

 

That sounds badass... Let us know how it goes. Nothing like an almost free mod to help out your fellow org'ers.

 

I have experimented with connecting a hand vacuum pump to the VIAS fresh air inlet, and applying vacuum so the VIAS stays open all the time... definitely loses low-end torque, so that's not so good. But I'd need some kind of RPM switch first, and it's not like I wanna spend any halfass amount of $$ on this

 

ImStockBaby.... "Maybe the fact that a 5th gen intake manifold would be much easier to find, and possibly cheaper than an MEVI.."

Big D.... I know the main difference between the MEVI and the 5th gen manifold that in the 5th , there two(2) seperate runners compare to the MEVI having only an increase in air volume due to the increase airspace once its activated.
Did you know that????

ImStockBaby..... even if it's easily available and maybe cheaper.. this thread speak for itself...has anyone done it yet???

 

Well actually yes I did. You however obviously didn't and just dug deep to find it, 2 days after I made my post.

 

Assuming the 5th gen intake manifold will raise the 4th gen HP close to 5th gen levels it is obvious it is far superior. At 5500 RPM the 5th gen IM is giving a 20 HP benefit while the MEVI is showing a 0 HP improvement. Due to the low end loss with the MEVI there is little if any increase in average HP. In my opinion the MEVI is only worth it for those who can get the JWT ECU (with extended redline) or automatics that benefit because of their wider spaced gears.

The 5th gen intake manifold can probably be gotten from a junkyard fairly reasonably or at least bought from a dealer without dealing with importing them.

Obviously there are some major hurdles to overcome to install a 5th gen IM on a 4th Gen and it may never be cost effective. Still looking at the potential gains of this I am surprised nobody has at least made an attempt at the swap. There is a guy who put a 3.5 in a 2k Max and even someone who stuffed a Maxima V6 into a previous generation Altima, yet no one has attempted this

 

Im in the process of doing this , but the only snag or holdup is not having enough info. I want to know do i need the 2000 lower intake manifold with fuel rails and injectors and if i do will these plug into 4th gen connectors. These are my only hurdles i have solved everything help . I cant believe nobody has even tried this . All i here are guesses not solid leads. If i can bolt it to my 96 without lower intake manifold probs i'am all set. If i just need to bolt the 2000 lower intake manifold with rails and injectors and just connect to my connectors i will be golden this way also. But nobody seems to know anything. Thank you

 

Putting the 5th gen manifold on would be a huge benefit to us 99.5 SE-L's who will never have the JWT ECU. I think there might even be a possibility that a 2K-2K1 ECU might plug into our harness and help to eliminate some hassle.

 

yeah, that does sound like a good idea. One of my older brothers has an old '94 SHO that he tinkers around with and he has the variable intake set up to where he can switch it open when ever he wants.

 

That's what I was thinking of doing... installing a small switch in an inconspicuous part of the interior which switches a relay that switches the VIAS Control Solenoid on w/o the ECU's signal being present.

 

First things first, 4th gens and 5th gens don't share the same type of fuel injectors, I'm not referring to just the size of the injectors, but the actual type(saturated vs peak'n'hold) You would have to cross reference the part numbers for the 4th gen heads vs 5th gen heads, then the 4th gen lower intake manifold vs 5th gen lower intake manifold.

TK

 

I've given up on the swap long ago. I'd just like to see someone cough,coughFrostycough,cough do what I was talking about. Experimenting with the opening point on the VIAS