Hey all,
I've been lurking these forums for quite some time reading about mods for these cars.

I have an 04 AT Coupe with a few bolt ons.

I recently stumbled on the DIY Manifold Porting stuff and wanted to know if there is anyone with real experience in porting these that is still around here.

Most of the threads have dead pictures and little to no results.

I have spent hours reading everything on here and my350 or whatever and literally 95% of it is useless

I just picked up a new bottom collector & a full plenum (top + bottom w/ TB) for some work!

I'm going to send the TB out to maxbore and bore the plenum opening to 64mm.

I also got Thermal gaskets for the head to Manifold and Manifold to Collector.

https://g35driver.com/forums/intake-...-manifold.html

^this thread probably has some of the best information.

I'm going to try to duplicate that to some extent.

But so far what I have collected is that I should;

Shave the posts off on the top plenum.
Bore Plenum opening to match TB.
Remove all casting imperfections & stamps on top & bottom.

Smooth out casting on bottom plenum for the 2 runners closest to the walls.

Polish / Sand Bottom & top Plenum

Mill down the two bottom runners about 5mm.

Port match bottom collector to head's & Remove casting extra material.

Port out lower collector openings about 1mm on each port.

Use Thermal gasket from Head - > Collector & from Collector -> Bottom Plenum
And then Throttle Body Coolant Bypass + Tune.

Anything else I am missing?

Anyone have any better ideas? I saw many ideas in the 35 page thread, but none of them materialized or if so then nobody posted any actual dynos in the thread.

 

Look at this new company, rj manufacturing .they are designing a lower intake or runners what ever you wanna call them. Looks promising. If you wanna keep the oem plenum, i would recommend the mrev2 lower plenum from motordyne. Also an nwp throttle body And a limp mode 4" intake. Those are the mods alot of guys are running now that are making good gains.

 

The problem here is that it's already great design from Nissan. I've looked into gasket matching, port matching and polishing the inside of the plenum. Not much room for improvement. The biggest room for improvement that I found was polishing the inside of the plenum. When done right I've heard of 3hp gains. But I have read about lost HP too when over polishing. As long as you have extra parts, it might be fun to experiment, but I wasn't gonna risk screwing myself for a negligible amount of HP.

 

There's a reason why the MREV has been so popular to the original 'Driver crowd, and it's not just because Tony has been on the forums for a while before he decided to do the R&D to make the MREV. Search for those threads. You can also find threads about imitation failures and Tony has actually explained why.

 

MREV2 hasa very stupid price for a close to 0 gain.

I was considering an MREV 2 until I saw the terrible dynos (3-6HP gain for $400).

From what I have read around here, people have made much power power than the MREV2 for DE engines while doing their own stuff.

There are a few people who have posted 10+WHP gains from manifold work.

I believe that with the heat shielding gaskets + the manifold work I should be able to make even more than that with a good tune.

The manifold is not at all a good design, its actually one of the worst I've seen across all cars.

Also I found nothing about this RJ manufacturing. Do you have a link?

 

Man, this is an old *** platform. The bugs have been worked out regardless of your thoughts and research. I don't mean to discourage you, but best case scenario will yeild you 1hp over previous companies r&d. And that's really only if you find a flaw in the other designs that have taken on this endeavor. I just highly doubt this ttee will produce much fruit.

 

And there have been many people who have had gains by actually removing all the casting imperfections and porting out the lower plenum & collector & polishing the top, etc.

MREV isn't meant for this, its meant to bolt on and go. And as such that's why it doesn't make much power.

What I have seen on this forum over everything, is massive laziness on the part of the community at large. Most people unwilling to try something new and many people who keep saying they will dyno their cars and never get around to seeing any gains.
Also many people who just simply disappear while "working on a project" and never return, or return like 1 year later with everything changed and no conclusive evidence.

Its completely different from Honda-Tech, where I have been a member for a long time since I have a fully built turbo Honda.

This car is just my daily and I am doing some tinkering :P

 

From what I read, NWP throttle body loses power on G's. Every dyno I have seen makes it lose power across the entire RPM band and then gain a bit at the top (but nothing over peak, the peak is always lower).
The throttle body is way too big for that manifold. Only the Altima/Maxima guys have had any good gains with NWP stuff because they have a different manifold and have more room for changing its design due to the transverse mount.
The angle on the G/Z manifolds restricts the gains from huge throttle bodies.

 

i think this thread has a lot of interesting info. this was definitely the direction i wanted to go in before the guy completely disappeared.

http://my350z.com/forum/na-builds/60...maxima-tb.html


if you look at sasha's research, it has been shown the upper plenum been a big bottleneck.


http://my350z.com/forum/engine-and-d...5de-32-hp.html

read through this thread, sasha's original thread

http://my350z.com/forum/na-builds/46...ing-power.html

 

No there haven't. Show me one guy who gained power by ultra polishing. All tryers have lost TQ.

 

If you have an ig follow this guy. He had one of the most powerful NA vq35de's . The real problem with the plenum is the bottle neck at the top which you can see they tried to reduce. Also had an nwp tb.


Here is a link to his mod list and car running


Engine.
VQ35DE.
JE 12:1 compression pistons
Eagle Rods
JWT C10 cams intake. 300 degrees duration. 13 mm lift
JWT C9 cams exhaust. 287 degrees duration. 13 mm lift.
heavy duty valve springs. custom cam timing stop.
Multi angle valve job.
Deshrouded valves.
Ported Heads.*
Ported lower plenum.
Enlarged and gutted OEM upper plenum wih transition to 3.5" intake
NWP Throttlebody
UPREV GT MAF
3.5" Vibrant Cone filter placed infront of radiator
R35GTR Fuel Injectors
Walbro 255 fuel pump.
SGM Longtube Headers
3" Y Pipe
3.5" single exhaust. (custom)

Tuned with UPrev OEM ECU.
Innovative Tuning. Mustang Dyno.
335 whp. 278 lbft

 

Thanks alot man! this is some of what I was looking for!