Forced Induction Discussion of turbos , superchargers , and nitrous upgrades on the G35

Early 03 G35 + Boost????

Old 11-05-2018, 10:54 PM
Eric@TCGMiami's Avatar
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Cool Early 03 G35 + Boost????


here we go....

I am strongly considering going boost. driving the gtr has spoiled me quite a bit the sedan is just insanely under-powered and I am looking to spice things up a bit.

but I want to go a "Safe" route.

for those that do not know the 2003 in it's "stock" form is UN-TUNE-ABLE!

So this brings me to a big dilemma, I am going to have to go either A: Full Standalone for the ECU/TCU... or B: get a earlier 2004-2006 version and swap out "everything".

Keeping the stock setup and just tossing in a haltech I face another issue... clearance. the fan clutch takes up an important route for the intercooler piping.

I've gone through quite a bit going from fan clutch to e-fan back to fan clutch.

The electrical load on early v35's with the fan setup and controllers I used (SPAL PWM) it's just too much the cycling would prematurely burn out alternators.

Someone here (forgot who) was right, the fan clutch works just fine. on Initial acceleration with efans off car moves much better. BUT once they are on... it is 1 minute to 3 minutes of load and in bumper to bumper traffic with a/c on it is NON STOP. the load takes its toll. Plus the a/c is not as effective.

moving on....

The question will be then tuning options:

Uprev with oem ecu for 2nd gen V35
go Haltech

The next question is "bang for the buck"

Should I go with the Vq35 there will be quite a bit of mods to the engine that will need to do,

desired power output

750 PEAK whp (high boost)
500 whp daily

more important is the powerband.

i do not want a powerband that peaks at the end of the rpm range. prefer a 3800 to 6800 rpm range where the power is consistent.

so snails....

high compression pistons low psi (mid to big turbo size)
low compression pistons mid to high psi (low to mid turbo size)

so then we move onto the bigger question...

Why keep the VQ? using the haltech you can opt for other engines

LSX (or variant), etc...

bare in mind the objectives

daily driver on low boost
would be great to stay auto for laziness

most of you that know me, know that I like to keep a car for a LONG time. Don't want to be dealing with engine down issues.

Let me hear your thoughts fellow members.

Budget is about 20k

engine build, custom turbo kit
e85 compatible, auto trans build,
fuel system, ecu/harness swap/standalone.

Places where I have considered taking the car to:


anyhow, give me your thoughts. don't hold back comments or questions really want to hear you all out.

Old 11-06-2018, 12:27 AM
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Oooh, this is almost my dream build, except mine involves a T56!

With that kind of budget you should be able to LS swap your G using a full swap kit and standalone wiring harness. Grab a low mileage iron block 5.3 truck motor, freshen up the top end, ARP studs, head gasket, springs, LS3 cams, etc and you'll be able to snap half shafts if you turn up the boost too much.

I've done a bunch of research awhile back when I was bored, pretty sure you can get all the parts for $10k conservatively, that leaves you plenty for supporting mods and labor. A 700 hp tune should last for years and years no matter how you drive it with a good tune.... plus when it finally does blow up it's super easy and cheap to rebuild and really make into something unique.

Honestly, if I had that kind of money to play with I'd start with a 2007 sedan, swap it, and then swap all the nice parts from your current G onto it, entirely for the interior and exterior aesthetic upgrades. You'd be able to drive your current G while the swap was being worked on. OFC I have no idea how much you've dumped into your 03 over the years!

And PLEASE post it on here whatever you get built!

Last edited by cswlightning; 11-06-2018 at 01:01 AM.
Old 11-06-2018, 01:29 PM
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Eric is good about posting here. Amazing mileage on that G35. I'll do some research Eric but as you know the early G35 sedans were... weird in many unique ways.
Old 11-08-2018, 01:13 AM
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Looking at the G37 with the VQ37VHR

can get a wrecked one from copart for under 1k.

Seeing the power in stock form O.o

Since I am strongly considering just going full standalone I can run the bcm from the 03 for internal electronics and stuff and run the engine/trans from the standalone.

Magical question will be

vhr with auto
vhr with manual...

The GTR has spoiled me in ways that are unexplainable, But the comfort of the G is beyond outrageous...
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