Since the internals of the early RWD & FWD VQ35's block and head are supposedly identical, what accounts for the huge difference in power between cars with weak VQ's (like the Altima and Frontier) versus an '04-'05 era 350Z?

The only things that I can think of that will account for the difference in about 40hp would be the RWD's intake manifold might flow better and the RWD's ecu is set up more aggressively. Anybody know anything else that may be a reason?

Ultimately, I'm using this info as a basis to decide which FWD VQ's would be best to choose for an s13 swap. Typically, I see that the Altima/Quest/Frontier VQ's are cheaper than the more powerful Maxima VQ's. But if the power can be easily recouped with ecu tuning and swapping on a RWD manifold, making decisions would be even easier...

Exhaust manifold/intake manifold/ecu...

There is really nothing else it COULD be... 40 hp does not sound unreasonable for those three things, and really 40hp from a tune alone does not seem completely unreasonable...

The compression ratio is different. For example 05 Altima 3.5 is 10.0 and 04 350z is 10.3. I'll have to dig some more to be sure but I believe the pistons are different.

nissanmstr wrote:The compression ratio is different. For example 05 Altima 3.5 is 10.0 and 04 350z is 10.3. I'll have to dig some more to be sure but I believe the pistons are different.

Plz do. And plz post links supporting your info, because everything I've read says the internals & compression ratios are the same. Like this:

http://autos.msn.com/research/...97476

All my info is from factory service manuals. I'm going to get the parts department to check parts numbers, I know the cylinder heads have different part #'s. I have an 05 altima 3.5 and an 06 z 3.5 at home but I haven't pulled them apart yet. I'll do some digging.

I noticed that the RPMs are lower by 400 on the altima and quest. Intake/exhaust/ecu for sure. It's going to take me forever to come up with the money to do the swap. Guess that gives me plenty of time to do my research...

nissanmstr wrote:All my info is from factory service manuals. I'm going to get the parts department to check parts numbers, I know the cylinder heads have different part #'s. I have an 05 altima 3.5 and an 06 z 3.5 at home but I haven't pulled them apart yet. I'll do some digging.

I just looked up a few FSMs and 02-06 altima are the only VQ35DEs besides the Pathfinder to be listed at 10.0:1 (of the ones I checked). 2007+ altima, Muranos, Maximas, 350Z, G35, FX35, are all listed at 10.3:1... I wonder if that the 10.0:1 is a typo in the altima's case - we've seen typos in the FSM before.

A check of the piston part numbers would be informative, if the piston part # is different then maybe they really are different.

I think intake, headers, exhaust would be enough to give you the power you are looking for. I have a maxima and with about $1000 worth of mods I'm pretty confident I could pull on a z/g. you can put a Z intake manifold or keep stock manifold and use NWP engineering phenolic spacers... advance your timing, AFR tune and you'll be smoking z's all day.

btw which vehicle do you want to swap the vq in?

nzelinsky wrote:btw which vehicle do you want to swap the vq in?

S13. It's cheaper to convert a FWD VQ35 to run in a RWD platform than it is to buy a RWD VQ from the Z or G. But I don't wanna do it if I've gotta play this huge game of 'catch-up' just to match the RWD VQ's power.

If it's just simple stuff like the intake manifold/exhaust plumbing/ECU, then great. But if the heads & cams are different and non-interchangeable, then I don't want to bother with the FWD version.

Nealoc187 wrote:
I just looked up a few FSMs and 02-06 altima are the only VQ35DEs besides the Pathfinder to be listed at 10.0:1 (of the ones I checked). 2007+ altima, Muranos, Maximas, 350Z, G35, FX35, are all listed at 10.3:1... I wonder if that the 10.0:1 is a typo in the altima's case - we've seen typos in the FSM before.

I think it's a typo. Not that MSN autos is the definative source for car info, but even the comparison link that I post above lists the same compression ratios for the 2004 models of Altima, 350Z and Quest. But they all have wildly different power production...

Nealoc187 wrote:A check of the piston part numbers would be informative, if the piston part # is different then maybe they really are different.

Yes, that would be really helpful. Along with part numbers for piston rods, cams, valvesprings and retainers.

I've read a bunch of info on this on maxima.org and from what I understand the engine internals are same. (cams, pistons, etc) but it has a different intake manifold and different injectors I know for sure.

nzelinsky wrote:I've read a bunch of info on this on maxima.org and from what I understand the engine internals are same. (cams, pistons, etc) but it has a different intake manifold and different injectors I know for sure.

the compression ratio is different, but all the internals are interchange able. the heads are the same too for all 02-05 vq35de non-revup. a lot of the power difference is the intake manifolds, the exhaust manifolds, exhaust, cats, and tuning. the injectors have different part numbers for some reason, but are exactly the same.

Finally! An authority on the subject! Thanks Irax... That was precisely what I needed confirmed.

you're welcome Bob Makihara

Lolz... Thumbs up for Irax!

I have wondering the same thing although with a different car. I have a Pathfinder and have been trying to figure out what parts interchance since the block is the same. I understand ECU, intake, manifolds, possibly pistons are differnt. I am trying to figure out what parts from a z can I swap since the pathfinder aftermarket is no where to be found. In theory could I take a 350z ecu and intake and see gains on a path?

I have a pathfinder as well. mine is the simpler manual tranny VQ, and methinks it would be great to see a write up on that.

Ultimately, I'm using this info as a basis to decide which FWD VQ's would be best to choose for an s13 swap. Typically, I see that the Altima/Quest/Frontier VQ's are cheaper than the more powerful Maxima VQ's. But if the power can be easily recouped with ecu tuning and swapping on a RWD manifold, making decisions would be even easier...

correct me if im wrong but the s13 was never fwd it was always rwd so why is he trying to put a fwd VQ in his car? Sir the simple answer to your question would be to save and buy yourself a vh45de the swap would provide more then the latter and ive found a motor on ebay http://cgi.ebay.com/ebaymotors/1996-Inf ... ccessories cheap to huh? soo you dont know how to swap the motor into your s13 http://www.nicoclub.com/archives/nissan ... ation.html dude this motor produces 310 hp given you have VTC the motor shipped is 500 time spent installing one week of nonestop labor time spent enjoying the effin beast priceless hope i helped