VQ35DE engine performance upgrade - opinions wanted

[sigman70]

Hey all...I'm in the process of pulling the engine on my 2002 Pathfinder (casualty of the power valve screw issue), and have been searching for ideas on
increasing the performance of the engine (VQ35DE)...as most of you probably know, there isn't much in the way of products available for this Pathfinder engine, but I did come across some things that I wanted to get people's opinion of. (NOTE: I do realize this is not a race car, but I just would like to see if there's anything I can do to increase the power on it)


This is an engine kit I found:

http://www.importperformanceparts.net/i ... issan.html

And another one:

http://www.rhdjapan.com/power-enterpris ... q35de.html

This is a cam I found:

http://www.4x4parts.com/i-18916837-high ... -cams.html

A performance module:

http://www.4x4parts.com/i-18980869-v-fo ... odule.html

A place that does custom headers (since I've been unable to find anywhere that has them for this engine):

http://www.stainlessheaders.com/customheaders

I already have a dual exhaust and cold air intake that I had put on before the engine seized, so I will still have those for the replacement engine. Just curious to get some opinions on all these and if anything else would be needed for them (like if I got the engine kit, are there other things that would need to be upgraded). Thanks!

[atraudes]

I'm with you; if you can bump up your power, why wouldn't you at least consider it?

Those first two are great finds and definitely necessary if one were to turbo or super charge, but do you know if they'd increase power by themselves? The first site sort of implied that, but they were kind of dodgy in the power increase verbiage (intentionally, I'm sure). My understanding was that things like forged pistons and connecting rods were a necessity if you're going the blown route, but any power increases they contribute would be incidental.

As for the others, I'm sure they'd all make a difference; it's just a matter of whether they're worth the cost to you. I do really like that cam option though. I wish I knew of a way to identify them on sight. I'd start pulling valve covers off at pick-a-part places

4x4parts.com tends to resell other brands under their own name; it's highly possible those cams are available elsewhere for cheaper. It likely won't be a colossal difference, but it's worth a look.

[sigman70]

That's a good question...I'm not sure if I only were to do the engine kit itself, if it would increase power...I remember reading a long time ago on another site that if one were to add a turbo, that the internals of the engine would need to be upgraded, and that's what I think all this would do (like you said), but I am by no means any kind of expert on this! Maybe someone can chime in and let us both know.

Thanks for the tip on the 4x4parts site...I didn't know that they did that, so it is worth looking further to see if the cam could be found cheaper.

What I was thinking along the lines of, was finding a used engine (hopefully for around $1000), then getting an engine kit & cam installed which would hopefully give more power then if I went the route of getting a re manufactured engine (which from what I've seen online are around $4000 - $5000). And since the engine is going to be out of the vehicle, I figured I might be able to save on the labor if I just brought the engine to a shop versus them having to try to install everything with the engine already installed (I could always add the headers myself later). But like I said I no kind of expert so just wanting to see what others think.

[jroo]

you may see a small bump in power for the kit because it looks like the piston will be higher compression. Not sure what stock is but they are listing close to 11 so you may also worry if it can run on premium fuel? The biggers concern for me would be the module. I saw those years ago and thought they worked but mainly on a stock engine. I thought it just doubled over the stock ecu. I dont know if it would help you on cams, headers, and internals. You would have to ask to be sure. If you go that serious, you may have to look at true stand alone to make it work.

[4xq]

There is a vq35 engine thread here, you might learn some stuff over there, altho you may have to go back a few years to when these engines were the latest thing - I think a lot of performance tuning is now done on the 4.0 v6.

The later Z's used a 287 hp version of this engine - bigger valves, different cams, etc. Since you have a manual transmission, it *might* be possible to use a long block from that and hang all the necessary Pathfinder parts on it. You would probably need an aftermarket ECM. That is just a guess tho.

Check car-part.com for engine prices. Pathy engines can be had for 400.00 from the wreckers.

[sigman70]

you may see a small bump in power for the kit because it looks like the piston will be higher compression. Not sure what stock is but they are listing close to 11 so you may also worry if it can run on premium fuel? The biggers concern for me would be the module. I saw those years ago and thought they worked but mainly on a stock engine. I thought it just doubled over the stock ecu. I dont know if it would help you on cams, headers, and internals. You would have to ask to be sure. If you go that serious, you may have to look at true stand alone to make it work.

Thanks for the info! I did a little more research on that module, and it has a lot of bad reviews...you can't customize anything with it, so like you said I would probably need to go with a different unit.

[sigman70]

There is a vq35 engine thread here, you might learn some stuff over there, altho you may have to go back a few years to when these engines were the latest thing - I think a lot of performance tuning is now done on the 4.0 v6.

The later Z's used a 287 hp version of this engine - bigger valves, different cams, etc. Since you have a manual transmission, it *might* be possible to use a long block from that and hang all the necessary Pathfinder parts on it. You would probably need an aftermarket ECM. That is just a guess tho.

Check car-part.com for engine prices. Pathy engines can be had for 400.00 from the wreckers.

Hey thanks for the heads up on the VQ35 engine thread...I apologize that I probably should have put this into that thread! I haven't had time to look at all the posts in that thread, but I just glanced at some and the majority of them are dealing with the 350Z VQ35DE (which isn't surprising, lol). I actually have an automatic transmission on my pathfinder, so I don't think I'll attempt to go with a Z engine. I checked that car-part.com website...cheapest engine listed was $950 (there were some that said to call for price). I got a number for a local shop here that has very good reviews that I'm going to ask and see if they would be able to source an engine and what the cost would be.

[sigman70]

Hey all...I'm in the process of pulling the engine on my 2002 Pathfinder (casualty of the power valve screw issue), and have been searching for ideas on
increasing the performance of the engine (VQ35DE)...as most of you probably know, there isn't much in the way of products available for this Pathfinder engine, but I did come across some things that I wanted to get people's opinion of. (NOTE: I do realize this is not a race car, but I just would like to see if there's anything I can do to increase the power on it)


This is an engine kit I found:

http://www.importperformanceparts.net/i ... issan.html

And another one:

http://www.rhdjapan.com/power-enterpris ... q35de.html

This is a cam I found:

http://www.4x4parts.com/i-18916837-high ... -cams.html

A performance module:

http://www.4x4parts.com/i-18980869-v-fo ... odule.html

A place that does custom headers (since I've been unable to find anywhere that has them for this engine):

http://www.stainlessheaders.com/customheaders

I already have a dual exhaust and cold air intake that I had put on before the engine seized, so I will still have those for the replacement engine. Just curious to get some opinions on all these and if anything else would be needed for them (like if I got the engine kit, are there other things that would need to be upgraded). Thanks!

I found another option...I can't quite tell if this is considered a header or just a manifold replacement (it comes with the pre-cats on it and is supposed to be a direct fit), as they mention :

http://www.autoanything.com/exhausts-mu ... 5A0A0.aspx

It's definitely a lot cheaper then going with that custom header from the link I posted above, but not sure if it would give any real increase as compared to those headers?

And I forgot to mention before that I found this guy on Youtube with his turbo Pathfinder:

https://www.youtube.com/channel/UCtlilo ... vLgog/feed

Maybe I should just ship mine over there and have him turbo it, lol!

[4xq]

Well, for some reason I put in engine block price. Seems I have lost a powervalve screw between the ears. Gotta slow down and reread what I post.

[sigman70]

Well, for some reason I put in engine block price. Seems I have lost a powervalve screw between the ears. Gotta slow down and reread what I post.

Lol, no worries...I almost did the same thing when I was searching!

[351cleveland]

If you are going to go the route headers, i am in the middle of making some doug thorley shortie headers made for a 2005-2009 pathfinder/xterra/frontier with stock magnaflow replacement cats for 2005-2009 pathfinder work on my 2003 QX4. Still waiting on my doug thorley 4.0l pathfinder b-pipes to arrive, then im taking it to A 4x4 shop to install and finish off the exhaust to fit. It should work, as i have already mated up the ports to one of my old stock manifolds, and they match up perfectly. Will update everyone when the project is finished.

[sigman70]

If you are going to go the route headers, i am in the middle of making some doug thorley shortie headers made for a 2005-2009 pathfinder/xterra/frontier with stock magnaflow replacement cats for 2005-2009 pathfinder work on my 2003 QX4. Still waiting on my doug thorley 4.0l pathfinder b-pipes to arrive, then im taking it to A 4x4 shop to install and finish off the exhaust to fit. It should work, as i have already mated up the ports to one of my old stock manifolds, and they match up perfectly. Will update everyone when the project is finished.

Hey there...thanks so much for the reply! Yes, I would really be interested in hearing about how this goes! The one link I posted about the custom headers is very expensive, and I've almost pulled the trigger on these (which again I'm not sure they are actually headers or just manifolds - they mention both in their description):

http://www.autoanything.com/exhausts-mu ... 5A0A0.aspx

Not sure if these would give me any type of performance increase??