axion

anyway to swap one of the '02 max engines into a 4th gen?

Daniel B. Martin

Since the VQ35DE engine is a member of the VQ family you might expect this swap to be almost a "drop in". The problems, if any, will be with the electronics. The new engine may require a matching Engine Control Module and some sensors which are not already in a 4Gen Maxima.

gtr_rider

iTrader: (50)

"so your saying theres a chance" - dumb and dumber

Sonic

"Yeah, like one in a million"

Whitemax

It's all about the Chedda'....

vmok

well... even the Honda guys sometimes swap the harness and ECU with the engine...

in terms of fit, it should fit. in terms of displacement, it's bigger. ecu calibration might be off though.

-V

Jeff92se

iTrader: (82)

Okay spend about $3,500 to $5000 for an engine swap and you yield 260hp? Not a very good way to gain hp to me. I would just bolt on a super charger for the 190hp engine and go to town. Kit costs less then $4,000? And some of these guys are getting pretty massive hp.

DA MAX! I'm at it again!

Daniel B. Martin

I'd like to know whether the VQ35DE crank and rods are interchangeable with the VQ30DE parts. If the answer is yes, 4Gen owners have a wonderful opportunity to stroke their engines using factory parts. That's not going to get you a full 260 horsepower, but it could be a low cost and completely concealed power enhancement.

Shingles

hmm... I think since this is the VQ family I bet that the block is the same... that would probably mean that it's probably bored and stroked. hmm this would be a good options... give it a year or so, one would be able to pick up VQ35 from the yard for "cheap". Two years ago, while I was at the yard, there were two good running VQ30DEs for $750.

-Shing

Daniel B. Martin

VQ30DE bore = 93mm, stroke = 73.3mm.
VQ35DE bore = 95.5mm, stroke = 81.4 mm.
A lot of the displacement gain comes from the longer stroke. If my arithmetic is right, a stroked VQ30DE would displace 3318 cubic centimeters. We could call it the VQ33DE engine.

Whitemax

So what your sugesting as a possiblity is to bore our block , and we *could* be able to use the crank and piston from the new VQ35? I like the way that sounds..... especially since I'm going to have to do a rebuild one day anyway.......

Shingles

I think what Daniel is getting it though is something that could potentially be less costly... crank + rod only... no bore.

Hmm...

-Shing

Daniel B. Martin

Nope. I wouldn't bore the 4Gen block because the maximum overbore is only 0.20 mm, a trivial amount. I'm just thinking out loud about substituting the a VQ35DE crank and rods for the corresponding parts in an otherwise stock 4Gen VQ30DE engine. That would result in an engine with the same bore as the VQ30DE and the same stroke as the VQ35DE. It works out to 3318 cc.

Whitemax

Makes sense. Good to have you around Daniel

axion

But here's the thing...say u got a lot of miles on your max, so do an engine swap, hopefully you'll be good to go. And THEN supercharge THAT! 60 HP + however much you get from the super, that's quite a bit. Well, if this is possible, who would be able to do it?

Cumalot

iTrader: (8)

"when I thought you can't come up with anything dumber...you come up with this idea...and completely redeem yourself!"


or something like that, not sure if I got it right.

Daniel B. Martin

Who could do it? Stillen, in a demonstration vehicle.

Daniel B. Martin

Yes, exactly. Let's consider another consequence of this hypothetical VQ33DE engine. The volume of each cylinder in a VQ30DE engine is 498 cc. The compression ratio is 10.0 to 1. This tells us the volume of the combustion chamber is 55.3333 cc. The proposed installation of a VQ35DE crankshaft changes the volume of each cylinder to 553 cc. Consequently the compression ratio is increased to 11.0 to 1. Higher compression has the advantage of increased power and the disadvantage of requiring fuel with a high Anti-Knock Index.

The idea of using a VQ35DE crank as a low-cost "stroker" in a VQ30DE engine is based on a slew of assumptions. To list some of them ...
- both blocks have the same deck height (that's the distance from the crankshaft main journal centerline to the surface which mates with the cylinder head)
- both cranks have the same main journal dimensions (width and diameter)
- both pistons have the same wrist pin diameter
- both pistons have the same wrist pin hole to crown distance
- both pistons have the same weight
- both connecting rods have the same small-end width
- the VQ30DE block has enough "elbow room" in the skirt area to accommodate the VQ35DE crankshaft counterweights

None of these assumptions is completely unreasonable, but I point out that they are only assumptions. I have no "insider" information which will confirm or contradict these assumptions.

Jeff92se

iTrader: (82)

Not to be a spoiler but if the compression ratios are different and the volume of air is different, we can reasonably assume the ecu must be reprogramed to accomodate it. Now fuel can be done fairly easily by the S-AFC or just a crude FPR, but the timing issue w/ the rasied compression would worry me. You also cannot assume to much about power becuase you still have the same heads as before. You also have the same TB and MAF. If these become one of the airflow limiting factors, then full hp gains will not be realized.

Daniel B. Martin

I agree that keeping the 3.0 liter intake, throttle body, sensors, and exhaust system will prevent the 3.3 liter engine from achieving its maximum power potential. However, I believe those parts will serve quite well up to, say, 5500 rpm. Between 5500 rpm and red line they will be performance limiters. I don't see the need to reprogram the Engine Control Module. It will still respond to the same signals from the same Mass Air Flow Sensor and the same two front Oxygen Sensors, to control the same six fuel injectors.

I envision the VQ33DE engine as providing significantly more low-end "punch" than the stock 4Gen engine. This is the kind of power enhancement you will feel and enjoy in everyday driving.

Jeff92se

iTrader: (82)

I certianly would hope it would work but w/ higher compression, the ignition maps might or might not be correct. Increased comrpession usually means less timing advance is needed(unless the heads are very good design). Too much timing might mean knock, which means det sensor kicks in, meaning the timing gets pulled way back, which means less hp vs if the timing maps were done right to begin with.

Daniel B. Martin

I agree with all of your points. You are correctly pointing out that changing the stroke of a modern engine without changing everything else will not produce the best possible result. I'm saying it would be good enough and also conceding that I have no evidence to support this opinion. Everything I've written in this thread has been speculative.

philpoe

iTrader: (4)

Maybe that's where a new ECU could come in.
While this one may be "too" custom, maybe something like The Racer's Groups UNICHIP product (formerly known as The Program) could really make it shine.
Now how to get those variable intake runners on board

Shayyadin

I feel like I just got about fifty times more knowledgeable in engines reading this thread. I have to admit all I really knew before was "intake, compression, power, exhaust." Quiero mas.

Where can I go to learn such things? (Aside from engineering school... I'm at Bennington college studying philosophy + metaphysics, and I'm lovin' it.)

Thanks,
Shayyadin

philpoe

iTrader: (4)

I went to copartfinder.com a few months ago and only saw 1 2000+ Pathfinder. Go there now and have a shopping spree! 17 at last count. Now how to get that variable runner system on board!

NeverEnough

One thing that may help is a book called, if I'm not mistaken, "John Lingenfelter on Modifying Small Block Chevy Engines". It sounds like it has nothing to do with an overhead cam, multi-valve engine, but it is still an engine, and this man knows way too much for his own good. It is easy to read, with good theory and application data, not to mention some cool pictures. You can sit down at Borders or Barnes & Noble and read it in an afternoon. You will leave there as if you had just watched a marathon of fu flicks, ready to scream and kick someone's ***.....or maybe I'm just a huge gearhead. Anyway, it is very informative, and thorough, covering everything from forced induction to exhaust, and everything in between. And, the best part of it is that it was all written buy the man who modified and drove the current "Car and Driver" record holder for top speed and 0-150mph-0. Hope this has been helpful for you. Let me know what you think if you do decide to read it.


Later on-
Lee DeVine

loup1276

there was an article in sport compact car about a year ago they said something about doing that... but wait guess this it was for a 240sx... they gave all sorts of numbers as far as bore stroke etc... and they reason as to why they prefered this over the 4cyl turbo motor in japan...can't for the life me rember what month or year the magazine was but i know it was thoroughly discussed...louis

Pmp-n8a

in the end you'll get beat by a boosted maxima...so why not just save the money???

Pmp-n8a

in the end you'll get beat by a boosted maxima...so why not just save the money???

boy o boy...it would be fun to see a 11:1 boosted maxima though....hahaha:P

SuDZ

That is a great magazine and you see a lot of Nissans in there usually. I think the 240sx you mean is there "Project 240sx". I know the article your talking about.

SuDZ

JDM4LIFE

iTrader: (2)

on the remark of 11.0:1 plus boost... are you nuts? it'd be sweet for about the first 3,000 rpms

as far as boring out the engine, it'd definitely be too thin. considering the people discussing this are considering boost as well, it'd be wise to do something such as iron sleeves. you've already got the block out and all, so might as well go for it. i'd definitely go for the swap before the s/c though. think about how unique it'd be. sure, it'd be great to have a boosted max, but how about having the first vq35 4th gen? even if someone else were to do it first, i'd jump on the chance if i had the cash flow. i haven't had a chance to check out the vq35 in the max but from the one i saw in the altima, it's quite bulky. the engine cover looked like it might have a slight chance of causing a fitment problem. in any case, having a "stock" 255 bhp under the hood is sweet. that 255 is rated on a stock engine, considering most of us have intake/exhaust and such, you could definitely pull some decent numbers on the dyno, with no boost even it's about time someone follows along the honda/acura path. i'm all for it!!

cbr2

iTrader: (1)

I got an engine for $400 w/ 80K on it. If someone wants to take it and try it out on one that is not in their car just in case it does not work.. If it does swap it in after you got the bugs worked out.

Pmp-n8a

i was joking

i am fully aware this would be a dumbass thing to do:OP

Axra

Will someone explain to me how changing the rod length will result in a longer stroke? If I am correct stroke is just piston travel in the cylinder, so unless you change the crank dimensions how would this create a different stroke.

As far as compression you could always use a lower compression piston in conjunction with a longer rod to achieve the 10:1 ratio. However with a longer rod wouldn't you lose torque to gain HP? The crank would travel faster nearer to BDC as opposed to TDC.

Black VQ

Is that you'll have the power from the swap, and still be open to the option of an S/C. Am I right, or am I right?
Same thing with my friend that owns a Civic. He just wanted to spend around $2k for a turbo kit on his D16 SOHC engine. I showed hoim places where he could get a B16 DOHC for less than half the price. With installation, he'd still be ahead in money terms. The main point was that he'd still be able to turbo the B16 later if he wanted, and its the same issue here.
If you just S/C a VQ30DE, that's about all you can do. But if you stroke it first, you make a lot of power, and still have the option of an S/C.

MaxSE98

if anyone plans on trying the swap get the tranny too, the new maxi comes with a 6speed if im correct, it should be able to handle the higher power capabilities of the motor. so the chances of stripping third gear (not that i know from experience or anything) should be significantly less. im glad that at long last people are looking into real options instead of just buying a "kit" that has all the fun stuff done already. back in the day it was comon to use a diesel maxima crank in a 260z effectively stroking it. if the blocks are identical i dont see why it wouldnt work. i bet it would be a straight fit too because its in the place of where last years motor was which had the same block as vq30de. im going to look into this further, maybe i wont sell my baby

98sterlingmist

What kind of numbers are MardiGrasMax putting down. His VQ30 is bored 3.2 i think and s/c.

Keh mon

Has anyone does more research or actually tried this yet? Since Nismo is coming to the US this could potentially be a good thing considering they'll probably be making internals for the vq35.

Keven97SE

This theortical stroker kit Daniel and others are talking about would involve the replacement of two major components in the VQ30DE engine: the crankshaft and the connecting rods. If this theoretical swap of VQ35DE parts into a VQ30DE were possible, it would involve installing connecting rods with SHORTER main journal to piston wrist pin lengths and LONGER crankshaft stroke. The "stroking" action (...ewww) is provided by the increased crank throws. The connecting rods would need to be shorter to keep the pistons from slamming into the head at the other end on the compression stroke.

This whole discussion is regarding a theoretical upgrade that would allow the user to use off-the-shelf Nissan parts, which is why there hasn't been any talk of lower compression pistons. Where would you get them from? If they did exist, they certainly wouldn't be from Nissan. Also, I would personally argue that you should KEEP the 11:1 CR and instead have custom camshafts ground, albeit at exorbitant cost ($2000+ I'd guestimate). The cams would have increased duration and overlap. This increased overlap would decrease the dynamic compression of the motor by decreasing combustion chamber pressures and would thereby decreasing the tendancy to knock. It would also allow the motor to breathe better at higher rpms. I would also argue that the UK/middle east or 5th gen variable volume intake manifold be installed to further increase high-rpm breathability.

The combined effect of the 3.3L displacement, increased CR, hotter cams, and variable volume intake manifold would give a nice increase in torque and an even more substantial increase in HP.

More details:
I had to dig this up from around a year ago, but I actually did a full-blown cranking pressure vs. V/P index spreadsheet calculation on this exact upgrade. To maintain the same the same cranking pressure on a 11:1 VQ33DE as the stock VQ30DE, you'd have to add 18-19 degrees duration to the intake valve closure, ie add that much intake valve timing duration. This acts as a sort of pressure vent to the combustion chamber to keep temperatures down and hence increase knock resistance. At 18-19 degrees, you'd have the same knock resistance as the stock VQ30DE motor (same cranking pressure). The increased duration hurts torque over what the stock cams would provide on a "VQ33DE", but would still yield roughly a 5% increase in torque over a VQ30DE. The increase in high-rpm breathability with the almost 20 degrees increased intake duration would give a huge increase in HP, though, but only when coupled to an intake manifold that was correspondingly designed for the higher rpm flow, ie the variable volume intake manifold. Without the manifold, you'd choke a lot of the engine potential. The only downside to this engine configuration would be that the valve train likely would not be reliable past the stock redline, and the torque curve would still be pretty flat ("pulling") at 6000+ rpms, so you would also want to upgrade to stiffer valve springs as well as get the rev limiter removed or at least bumped up well past 7000 rpm. I don't have any proof on this, but I think it's very safe to say that this motor would make 300+ HP at the crank. It'd "feel" very similar to the VQ30DE below 5000 rpms (a little more torque), but would continue to pull through 6000/6500/7000 rpms and make gobs of HP.

All speculation, though.

Jeff92se

iTrader: (82)

*Jeff falls over dead after reading Keven's post* *thud*

Speculation has it that his head exploded from information overload.