Hi all

I'm a newcomer on the forum, i'm modifying my engine VG30DETT
I know increasing the turbo pressure will give me more power, but until what pressure shall I configure without breaking anything ? (please dont tell me i have to test )
i didnt find topics about it maybe I had a bad search so you could help me!

(I'm using wiseco pistons, eagle rods, stock head gasket)

thx

 

I know there is a language barrier between us, but adding more details about what you have done to your car is really helpful.

 

Hi Hov100,
thx for replying, hope you'll excuse my poor level of english I'm doing my best (just hope i'll be better with my engine)

I had a few problems of oil gaskets with my engine and decided to totally open it... and rebuild
it's not totally finished yet but at the end here are the new parts that will be in:
-HOWE radiator
-new stock clutch fan+blade
-jwt R4+ cams
-Viton Valve Stem Seals
-EGR Elimination Kit
-JWT HD VTC Springs
-JWT HD single coil valve sprin
-Ferrea Ti Valve spring retainers
-Deatschwerks Injector Sets 740cc
-AMS Underdrive Pulley Set (sorry Z4ever i didnt know...)

and then i should use Z1 GT675RS Turbo Kit (didnt order it yet)

are these informations usefull enough to determine how much pressure I can use with the turbos ?

 

including the pistons and rods, id say you can push well over 20psi @ 3000rpm, and i think with the new valve springs retainers you can rev an extra 1k, so you can probably go 8500 maybe 9, not that you would want to since your turbo's wont be efficient at that type of rpm. you need to find the right turbo and for that, you need to bring it to my shop lol, or take it to a local tuner that can see what turbo's you can use on each side so you can have max boost @ low and really high RPM.

these turbo's (according to the compressor map on the website) will serve you best between 21-26 PSI @ 7000 RPM and 16-18 psi @ 3000.. your going to need a good tuner to tune these turbo's to a precise PSI for every 1000 rpm and a really good auto boost controller if your going to want this for lauch type racing or straight's, or if you going to have a little more fun with corners and tracks, then these turbo's are actually a little too big, id suggest something around 40-50MM

also i would recommend changing the head studs (if you havent already) and adding a thicker headgasket. (if you havent already)

 

I don't see an ECU or custom tune anywhere on that mod list... so the answer is "don't touch the boost or turbos." The factory preset on all aftermarket turbos is more than the stock ECU can handle.

Stock ECU can't do more than 12psi without detonation, stock injectors can't handle more than 16psi (assuming stock turbos - this number drops for larger turbos), stock intercoolers can't handle more than 18psi.

With an aftermarket ECU, larger injectors, aftermarket intercoolers and turbos, I still wouldn't do more than 20psi without race fuel, but 20psi on aftermarket turbos (no matter which) will make the car a rocket.

 

Ok nice advices, thanks !

I'm not involved in turbos and i'd really appreciate your help to choose one!
wich brand, size etc and if you have some links or topics to learn how to calculate and choose them it'd be nice too

I changed the head studs with ARP main studs but let the stock headgaskets...

 

Hi Zlover

fair enough, i'll change the ECU it's in my program!
I'm rebuilding the engine for now, waiting to see if i didnt mistake before going further

This is the first time i repair a car (i didnt know how to change oil when I've begun) so I do it step by step... decided to do that to lear how an engine is working

that's why I really appreciate your advices and your help

thx again

 

to be perfectly honest man, i dont know what type of Car you want to have, your building this machine like a monster, but whats your goal in HP and why? If you go to my shop, Or any shop they will ask this question, i know i would, and the main reason is simple; goal = Customer Needs. if you want 20-30 PSI i have to find turbo's that will support this boost under high rpm. if you want The car for drifting, tracking, draging or endurance i need to know what mods the engine will need and how big turbo's you will need as well Since you must consider turbo lagg and components.. I strongly recommend you take it to a shop in paris (which is where it says your from) and let them help you. here in forums were limited and cannot do much with simple information. trust me man, Tunning shop = happy you

 

It's hard to fine a good shop in here, and there are only about 1500 Z32 cars in France
not many people repair themselves, less modify and more less modify that much...

My goal is to get 600HP without any risk of breaking the motor
i'll have a daily driving and would like to test on circuit, I dont want to have the max pressure if not needed, I dont need the biggest turbos, I'm looking for the most of power at low rpm

 

Hi guys

here is what I have chosen to continue my build:
(on Z1)
JWT dual pop intake
labree catbackexhaust
GT725R turbo kit

what do you think of that choice ? does Z1 have good price for this stuffs ?
is there anything else I would need that I forgot ?

 

did I say something wrong ?

 

I don't have the time to ask a load of questions or read through everything to find all the mods you already have, but upgrading turbos requires A LOT of supporting mods (larger injectors, larger intercoolers are highly recommended, aftermarket clutch, etc etc etc). So do your research and figure out everything you need, first.

Aside from that, change that Labree exhaust to Specialty Z. Labree used to make the systems for Specialty Z, then they had a falling out and Labree continues to sell Specialty Z's design. By buying it from Specialty Z, you'll be supporting a company that continues to do innovation in the Z32 market - Labree doesn't contribute anything to our community.

 

Just a message to share with you the repairing of my motor
I dont have much time to spend on it but the end has never been so close
added dual intake since my last post

 

Cool man, hope you get through it. It would be nice to see the final product!