JON054

Hey guys,

First post here but I picked up a built turbo 350z about 6 months ago and been bringing it to the level where I like it.

I just got a new ECU (Vi-PEC 350z ECU - new one) which has had great reviews and the guy installed it and tuned it to 12psi, and gave it some runs and he said it runs great perfect timing on the motor, but only came out with 300hp.

300HP seems very low for 12psi, am I wrong?

I'm running built motor (supposedly, but would've blown already if not lol), HKS Single Turbo GT3037 turbo with standard intercooler, running 98 premium, and oil cooler kit along with a bunch of other gadgets.

He said the coolant level was like 3L low so he topped it up etc before the dyno run. That's been fine ever since.

If anyone has any thoughts, is this a normal power level? I thought people get 320hp on 6psi with this kit, non built motor.

This is my car:

Conway_160

iTrader: (1)

Better pic of engine bay? Any more specs on the motor besides it's built? Yes 300whp at 12 psi is very low, people get more than that with superchargers.

JON054

Don't really know much, he won't give me the engine build receipts. One of the guys who was friends with him when he had it built said it was Low compression, and not sure but maybe 10:5 forged pistons

WeightLimit

iTrader: (5)

Yikes I think the DE is in the 280's at the flywheel stock.

JON054

JON054

Could this be something to do with my stock MAF sensor? The VI-PEC ECU has an internal 4 bar MAP sensor (http://www.vi-pec.com/ecus/iseries__pluginecu) - tuner didn't mention anything about it, we just used the boost solenoid that came with the old TurboXS ECU and hooked that in.

He also mentioned my inlet piping was running hot.

Not sure if any of this makes any difference.

Conway_160

iTrader: (1)

Well you have a small FMIC, I would say change out your intercooler and try to get as much info as you can on that motor. Until it can be proven beyond a doubt assume its a stock motor! Stock MAF should be good up to 400WHP on a turbo set up or 10psi'ish on a supercharger.

JON054

Do you think that FMIC could be the issue?

Well my friend knew the guy when he built it and he's confident it's low comp, he just doesn't know the pistons etc used. The car is also running 12psi so by now, i'm pretty confident its built in some form otherwise it would've blown at 12psi as I knew another guy who blew 2 stock motors on 6psi twin turbo.

Zivman

iTrader: (19)

it spikes to 12? it holds 12? tapers to like 5 at redline? so many variables to know what is going on. dyno graphs/AF ratios would help some

boost leaks?
bad tune?

Highway Riding

iTrader: (6)

That's a tiny intercooler and turbo. Swap those and retune.

Boosted Performance

iTrader: (14)

Before doing anything else, you will need to source a properly sized turbo for your engine, with a T4 turbine in order to get some good power out of a built engine.

DaveJackson

iTrader: (5)

Remember that it's not the psi that pops the engine, it's the torque and at only ~300hp you will not likely be generating enough torque to bend the rods or damage something else.
Please continue to assume that it is stock until you have conclusive proof. At stock, many people get away with ~400 lbFt of torque which usually translates to about 400whp.

iideadeyeii

iTrader: (6)

How much did you pay for this 300whp beast?

str8dum1

iTrader: (11)

the FMIC is properly sized for that turbo, that all part of the $$$$$$$$$$ HKS turbo kit. That HKS 3037 is very small with a t25 flange, 52mm so 300whp at 12 psi isnt surprising, but a little low. copuld be the compression, coulld be soft timing, could be alot of things

backpressure is probably 40psi

same turbo kit dyno for reference

evilscorp

10.3:1 is stock so 10.5:1 would be higher compression. Do a compression test and find out, intercooler is very small so not surprised the intake is getting to hot to create safe higher power.

taywan

iTrader: (53)

That doesnt sound correct-boost/power level. 12 psi "should" put you well above 400whp.

racer59

iTrader: (2)

Try running less boost U will prob make more power ,the turbine is to small for that boost on that size engine
The reason your power is low,is back pressure and charge contamination due to exhaust gas being forced back into cylinders

nathanwl2004

iTrader: (2)

Boost in and of its self does not equate to power. Additional airflow provided by a pressure gradient (ie boost) + additional fuel equals power. I would be very conscerned as to why your car is making such low power numbers. Not just because it isn't making the power you want it to but because it is obviously not running correctly.