92blackr1

Okay so my engine builder said i need a tune for my set up consists of a street port hks catless dp and 3 inch straight with a hks carbon muffler and some sort of intake im running stock everything else. I do not have the money for a power fc or haltech right now i have been looking at the pettit ecua limited and unlimited would i be safe with either one of these ecus and eventually i will get a power fc i just want to make sure i will be safe i dont care if i run rich as long as it wont hurt the engine

Dvst8

iTrader: (6)

You'll be safe with the pettit ecu.

XLR8

iTrader: (52)

I would keep the stock intake box, to be safe.

With a full 3" exhaust and a street port, you are going to have serious boost control and spiking issues with stock turbo's. Your intake temps will also dramatically raise above 12psi with a stock intercooler. This is not good for your engine, or overall reliability.

The Pettit ECU will protect you as far as the stock MAP sensor can read, which is around 14.7psi. You can push it a little more, but accuracy goes out the window, as it is only a 1 bar MAP sensor.

Personally, it is not worth having a little more power, boost, or response for a temporary time and rebuilding your engine because of it..

RENESISFD

iTrader: (13)

^ The OEM MAP sensor is a 2 bar sensor. It is based off of absolute pressure, not gauge pressure.

92blackr1

So with the porting my boost will atomaticaly raise?

XLR8

iTrader: (52)

Thank you for the correction.

Nonetheless OP, porting will increase flow, which in turn, can increase boost. The stock wastegates are only so big. As you begin to open the system, they will be over-run. Many people port the stock wastegates as they begin to open up the stock system.

I have seen a completely stock car go from 10psi to 14psi (spiking to 16) with...

Full 3" exhaust
Intake pipes

Every car is a little different. Ambient temperatures also play a role. If you add a ported engine into the mix, it can get sketchy.

I would keep the stock air box for sure....

92blackr1

Okay so would a stock air box and a k an n filter be better then a set of cone filters for keeping the boost undercontroll better or is that just gunna keep my air intake temps down and lessen dètonation

DriftDreamzSS

iTrader: (4)

That straight pipe is the main thing that will cause your boost to go too high if you had to narrow it down to one part. If you still have the stock cat I would put it back on and monitor boost to ensure you dont go above 10psi until you can afford an ecu and a tune. Years ago I learned the hard way and added a straight pipe to a car that was running excellent with intake, catback and aftermarket smic and blew my engine and destroyed the turbine wheels on my stock twins shortly after.

XLR8

iTrader: (52)

I think the Pettit Unlimited will play a big role for the OP. It's a pretty flexible ECU, but it does have its limit for sure. You're definitely right, the main cat is the big limiter for flow, as well as the main catalyst for keeping boost down with stock twins. Good suggestion.



OP, the stock air box will limit flow a little which will help keep boost down. Realistically, it will also help keep intake temps down slightly as the box draws fresher air with the snorkel. The greatest component for intake temps is of course the intercooler. The stock core is a joke. As you raise boost, which happens inherrintly from opening the system, your intake temps will sky rocket. It's all bad.

I ran a Pettit Unlimited with the same mods as you and saw 14psi with spikes to 16psi. I was always leery of it in cool weather. I also had a stock port engine. I would not have done it with a street port. Ported engines have better midrange and topend flow, which doesn't help your situation. I did this with a stock intercooler for a short period of time.

I also assume you have an upgraded fuel pump?

92blackr1

No i have a walbro and i wll not be raiseing boost on purpose if that is some needed info