Stock Turbo

[Skatelement]

What is the specs on the S4 stock turbo such as what is the max boost it will produce and would it help to use A boost controller on the stock unit?

[Phoenix7]

if you have stock fuel system then you're better off leaving it alone...

Now if you get a boost controller I would not go past 10 psi if you keep the stock injectors. You'll also need a fuel cut defender since the higher boost will cause the fuel to cut out...

Now a lot of 13BT guys, especially the S4 peeps, tend to have problems with boost spikes...the wastegate can't handle the increased flow and you can blow your motor by boosting so high without the fuel to back it up. To help with the flow, a lot of people port the wastegate and that helps with over-boosting...

How's your car running? how long have you had it? mods? Mileage?

[Skatelement]

Got the car with A coolat seal blown due to the electric fan failing, I plan going back to the clutch fan setup, The car is makeing around 9 psi but cuts out around 9. someone has added an external regulator with gauge showing around 30 psi. It has stock injectors. I just got the car and finding alot of what appears to be little half done problems, it has 180k. Going to get the engine built and street ported. Mainly I want to boost at leat 10 psi if possible. Would I need to change the injectors and reset the fuel pressure if so what injector size and pressure would you say would be safe for 10 psi boost. It has a fuel cut defencer installed by the previous owner. Along with a 3 inch down pipe free flow exhaust system.

[Phoenix7]

720CC secondaries and you might be able to get 12psi....but watch out for boost creep....you plan of putting a stock turbo on the new modded motor?

[RETed]

Mazda does not release specs on their turbos, except for the model # (Hitachi HT-18) and the turbine A/R (0.88?).

Please get "max boost" out of your head, cause it really has nothing to do with power.
It's all about airflow.
Any turbo can hit stratospheric boost levels given the right conditions.
The consensus is to keep boost around 10psi for best efficiency.

I don't recommend boost controllers unless you know what you're doing.
I don't recommend MBC's; I prefer EBC's due to their better control.


-Ted

[13bpower]

What can i do to get rid of the fuel cut out or is that not poseball,i did a t2 s4 swap and wired the n/a resister will that efect when use the t2 fuel pump???Id also like to know if it's common that a stock t2 manifold crack's???

[Phoenix7]

You can buy a fuel cut defender online...Racing beat might have one...if not then mazdatrix. I don't recall if any vendors on here sell them so ask them.

What resistor did you wire in? are you using an NA pump?

It's never OK to have cracks in your manifold...

[13bpower]

Originally Posted by Phoenix7

You can buy a fuel cut defender online...Racing beat might have one...if not then mazdatrix. I don't recall if any vendors on here sell them so ask them.

What resistor did you wire in? are you using an NA pump?

It's never OK to have cracks in your manifold...

I used the n/a resistor and know im going to put on a t2 fuel pump,would that effect me on anything. What does a resistor do? I had the n/a fuel pump and n/a resisrtor and my car run's perfect and floored it and never broke it. But like now im going to use my t2 fuel pump im afraid that i will break my motor.thank's for the help...I know it's not ok to have a crack on a manifold but id like to know if it's common.

[RETed]

Why you threadjacking?


-Ted

[Phoenix7]

Might as well as long as he has people answering....

as far as the relay, if it's getting full voltage at all times then it'll have bad mileage but it's better for the TII anyways....You're keeping everything and only replacing the pump?

RETed?? Any thoughts?

[13bpower]

SORRY.for highjakeing the thread i apologize,i will pm phoenix7 for further question.

[Phoenix7]

or make another thread.....either way will work....