flicktitty

Hi, I was just wondering as to what stock VG30ET motors are able to make (HP) wise. Such as pistons and connecting rods. Cause i am getting ready to rebuild my motor and i was hoping for about 470ish Horse power. I didnkt know if i should just use stock Z31 Turbo pistons and connecting rods or if i should use the Stock Z32 TT pistons and connecting rods. Or if there is something else i should look into. Also what cams should i look into getting i was thinking of the JWT S1 or S2's what do you guys think i should use? Also what kind of headwork should i look into doing? Also is there anything else i have forgotten? I know i will need to upgrade suspension and brakes and drivetrain as well. Well thanks in advance - Nick

jmw.81

The crank and rods will probably be able to hold that much power as long as everything is balanced nicely enough to keep things smooth. I seriously doubt the stock pistons however will be able to handle 470HP. You should atleast upgrade the pistons and get the whole assembly balanced.

flicktitty

ok, any thoughts on what pistons i should go with? Z32 TT? Or some differant ones. And i thought it might be better to get new rods since i'd be getting new pistons. I got the car non-running. So i have no clue how much damage there is. I figured better safe then sorry.

Velox ZX

Go to JE forged pistions... or weisco as a secondary option... order a set of standard bore Z32 turbo 8.5:1 forged pistons... should be between $500 & $750 Also request a set of rings. If you're rebuilding a turbo motor... then you're going to need to rebuild your turbocharger as well. So... you'd do a hell of alot better upgrading a T3/T4 hybrid turbo.. like a Garrett GT series GT28R or GT28RS. No offense to you... but if you're needing advise on this kind of thing, then you haven't been building, or rebuilding motors for any length of time so you don't need to go over the top on boost.. so the 8.5:1 CR should hold you pretty well up to about .70 BAR.

JD

AZ-ZBum

more than you can afford. way more than you can afford. no really. that much.

jmw.81

If you can afford aftermarket rods then go for em. But the stock rods are already forged and pretty strong. But the weakspot of all these Z motors (L & VG) is the cast pistons. Dont get me wrong, the stock ones can handle a decent amount of power, but they'll be the first thing to go if you do break something. I only say "weak spot" because the rest of the motor is can handle loads of power.

flicktitty

Yeah, Non taken. I knew someone would say this sooner or later. I have been into the car scene for about 8 years or so. But i got my Liesence 3 years ago and i just recently aquired my Z this past summer. I have about $6,000 to $7,000 in which i could spend i was originally gonna go and get a differant car but i thought that this would be a good way to learn more about cars and how they work. I have been doing some research on the VG motor so i know a little of what i am doing. IHave a few friends that are willing to help me rebuild my motor. And between my 2 friends they have rebuilt over 30 motors so this shouldn't be overly hard. And there is a machine shop that said they will do some head work for me so i have the places to get this done.

flicktitty

Oh, btw thanks for all the help guys. Any idea as to what fuel and computer mods to do? I know of the JWT ECU tune. And i was thinking of some sort of Piggyback system. Any thoughts on that? I'm sorry for all the questions just looking for some guideance from all the Z guys.

AZ-ZBum

none of the piggy back systems do very well in the Z31.

AZ-ZBum

WTF? Why waste the time on rebuilding the motor if you're only going to run 0.70 bar? You realize .70 bar is only 10 psi, right? The stock turbo motor will easily handle 12psi without even sweating. Even without an intercooler.

And the GT28? Don't make me laugh. That is hardly considered an upgrade from the stock T3. Take on a GT32 or even a GT35 if you really want to upgrade the turbo.

flicktitty

Yeah, i was kind of thinking of a turbo in the GT line most likly the 35, Ialso thought that .70 bar was alot low. You said the piggy back doesnt work very well on the Z31's so what would you recommend me using? AEM EMS? or a Microtech? Well thanks again for all the help. -Nick

AZ-ZBum

There's a lot of discussion about stand alone systems.

JWT custom programs ECUs for your car. But they may take three or four tries to get the bugs worked out completely.
A lot of people use (and are happy with) Mega-Squirt.
A few people are starting to program their own, but that's really only just getting started.

flicktitty

thanks again AZ-ZBUM! you are the man!

260DET

Sounds like you should have an aftermarket ECU, the best you can afford that a local dyno tuner is happy/competent to tune with. The initial outlay is a shock but if you are serious it is the best way to go for longterm reliable power. I use a MoTec myself but apparently these are very expensive in the US