GTM Performance Engineering: GTR Manifold Conversion
 

We are happy to announce our GTM GTR intake manifold conversion. Our custom cast lower intake manifold has a smooth transition from the VHR cylinder head ports to the GTR’s upper intake plenum. This allows the factory GTR upper plenum to be installed on the VHR engine.

For those wondering why we embarked on this, we noticed that the factory plastic manifold on the VHR would start to swell under higher boost pressures. The GTR’s cast aluminum plenum will not. Also, the GTR has a larger twin plenum design as opposed to the slimmer single plenum design on the factory VHR manifold. Generally, larger plenums will develop more torque than smaller plenums.

Also, due to the small inside diameter of the OEM fuel rails, we are offering a higher volume fuel rail system that comes in -6 or -8. The fuel rail system can be used with the factory style returnless setup or as a full return fuel system for higher power cars. This conversion kit can be used for forced induction or NA.

We are offering introductory pricing on our website here: GTM Motorsports*::*INTAKE*::*GTM GTR MANIFOLDS CONVERSION MOD KIT

Our adapter can be purchased separately or as a complete kit with the OEM GTR upper plenum and our fuel rails. Here are the links to the separate items:

GTM Conversion Manifold:
GTM Motorsports*::*INTAKE*::*GTM LOWER GTR INTAKE MANFOLD CONVERTIOD

OEM GTR Plenum:
GTM Motorsports*::*INTAKE*::*GTR UPPER INTAKE MANIFOLD

OEM GTR Manifold Cover:
GTM Motorsports*::*INTAKE*::*GTR UPPER INTAKE MANIFOLD COVER

GTM High Volume Fuel Rail (-6):
GTM Motorsports*::*FUEL SYSTEM*::*GTM High Volume Fuel Rail - VQ37VHR

GTM High Volume Fuel Rail (-8):
GTM Motorsports*::*FUEL SYSTEM*::*GTM HI VOLUME FUEL RAILS KIT -8


We have brought in a virgin test vehicle specifically to test the manifold on multiple levels: all the way from stock, untuned to tuned, tuned with intakes, OEM exhaust, aftermarket exhaust, turbo and supercharger kit. We will also be developing a strut tower brace that will work with the GTR manifold.

In the meantime, here are some pictures of the conversion:

So cool. Can't wait to see results. Do you plan to offer new piping to go from the intercooler to the throttle bodies for those of us with your Garrett kits?

Over the top today aren't we? lol

I'm going to say on a FI car this will make 25whp extra.

Of course :)

Sam

Dammit. Every time I think I'm done, you go and make cool new ****.

Wow I'm definitely purchasing this for sure. Can this work on my 7AT sam??

GTM, just curious why you guys didnt develop a new upper plenum exactly as gtr design but with increased diameter?

$2k for the kit ? :icon14:

all right... let's wait for the testing results.

Forgive me if this is a stupid question, but do stock fuel rails work with this system? ^^

EDIT: Actually, now that I think about it, if the upgraded rails fit in the factory location...that means the factory rails will fit this manifold converter. YESSSSSSS.

$700?? Hmmmm. Will wait for dynos.

Wait, so the throttle bodies are not in the exact same location, so my MHI TT kit will not work as a bolt on for this?

Also, is the throttle body opening on the manifold same diameter as oem throttle body?

I'd guess you'd just need two new pipes.

Sub'd for dynos!

Money is ready. Waiting for result :)

This is why I love GTM

GT-R and the VQ37VHR share the same throttle bodies, so I'd assume so.

Looks like ChrisUR's hardwork and time and money invested just went to waste as GTM has just trumped him with a finished and released project. Especially as he was saying his was going to be minimum of $1200. Nice work GTM. Sub'd for results

sub'd for results.

GTM,

Will the Greddy RX Upper Intake Manifold for GTR application work with this lower?

Awesome!! I cant wait to see results on both Na and Boosted Application. Interested for sure.

Hey Sam, you know, my car is a virgin test car at your shop...

In for some test results on N/A and Turbo applications

Good job on the lower intake manifold ! I might be very much interessted into this ! :)

I have two easy question. Would it be possible to know what is the diameter at the exit side of the lower intake manifold ?

Is the Oem fuel rail could work, or not ? *if custom holding bracket were to be made localy.*

Very interested but almost 2k in parts alone and Iam almost certain a us with FI will need a retune of at least $600 unless your going to offer a revised map?? Most of us are on a stock block so even more power would seem like a waste. Hell what do I know.......................@#$%^&*

soo nice but soo expensive!

I already have the cover and intake manifold, but no hardware (bolts, fasteners, screws etc). Can you supply the hardware? Will the adapter work with the oem fuel rail setup? Will the adapter come with new hardware to mate with the VHR?

Well, what's more important- the cost or the power it makes? Guys here spend $1500 on a catback that gives them 10 whp. If this turns out to make 20 whp, is it then not a better value?

but the cat-back makes noise.....:ugh2:

:tiphat:

But this is prettier, so I think that cancels out and we're back to the power question. I kinda doubt there's going to be a lot of NA gains, but I have a feeling it will really shine with boost.

obviously. no intake manifold really helps out N/A that much. boosted cars always benefit more with manifolds.

It's not completely finished yet... They are still working on the Strut brace, which ChrisUR at least has a posted design that is track tested. His kit (as he said once), will come with a strut bar as well. Or he will partner with a US manufacturer if one will work with him so they're made locally.

Good competition helps spurn progress as we've been waiting for GTM to release some info on this for what, 2 years now?

:tup:

I can't wait to see the final product.

Exactly. Having more options is always a good thing.

Yes, it will work with the 7AT.

Considering that the OEM GTR upper plenum is $958 by itself, are you really that surprised?

The stock fuel rails do not work with our lower manifold. Also, the inside diameter of the stock rails is quite small.

The throttle bodies are the same for both the VHR and the VR38DETT. That said, they are in different locations and since we make our own turbo kit as well as this conversion, it's only logical for us to have the appropriate piping available for both to work together. ;)

Thanks.

For your first question, that would be assuming that the port is a perfect circle, which it is not. That said, the cross sectional area of the port is 1669mm^2.

For your second question, the stock fuel rails are not compatible with this manifold. The crossover is not long enough to span the width of our lower manifold. You could cut the crossover and mounting tabs off the factory rails, weld on A/N fittings and new tabs to make it work, if you really want to.

The thing is, the inside diameter of the factory fuel rail is surprisingly small. As you can see below, we cut the crossover to get a better look at things and they are very small (~5mm =~ 0.197"). While the inside diameters of the rails themselves are 11.25mm as shown in the last picture, the restriction is in the feed lines and crossover.


That is precisely why we offer the various components for the conversion separately. You can purchase the lower manifold by itself along with one of our fuel rail setups (either -6 or -8). For the hardware, it will come with the adapter manifold.

Mike/Sam, for someone running this on an N/A setup, but in the future plans to go TT, which fuel rail setup would you recommend so they don't have to buy multiple setups? the -6 or the -8?

Ouch, too rich for my blood considering I have all of the power I will ever need. Nice products though!!!

-6 will do. -8 if you are planing on doing big power on E85

Sam

No big power, 500 streetable and normal pump gas. Thanks Sam! :tiphat:

This mod the more I think about is worth the price for what you get such as the material (and the quality of it) and there's no doubt it will make power. I could see this making +15whp with tune on NA and +25-30whp on tuned FI. Not to mention this GTR manifold makes ease for direct port nitrous/ meth into the runners.

Just be on the clear, per say I intall this on my 7AT with my 18 mhi kit with my VB of course included and 25R tranny cooler, I can't go past 520hp (assumption) because my engine will go Boom?

Your tranny will let go long before your motor blows.