Psi - Kw Ratio

[Rah]

hey guys, i am curious, if a stock standard car produces 147kw at 7 psi, if the boost was increased to 10psi, what kind of kW output would i be acheiving?

[salad]

Depends on the turbo

[bigcarl]

with my set up power goes from 274 rwkws at 17psi to 346rwkws at 25psi thats 10rwkw per psi but with a stock turbo it may only be 5 or 6 rwkw and that would give you an extra 15 to 18 rwkw but turning up the boost without additional mods to a stock set up would probably almost go back wards without a larger exhaust cooler and aftermarket ecu. then at 12psi with these mods 180 rwkws would definately be possible.

[LTHLRB]

i noticed on mine with stock turbo, 7 - 8 psi made 190kw and 11 - 12psi made 209kw. anything more than 12psi made bananas

[Devils_Advocate21]

efficientcy zone, 12psi just creates more heat, plus there is no direct rule for psi to kws, as theres so many other variables to include that can alter results, ie: exhaust, fmic, fuel, filterchoices, as well as outside or intake temperature (cooler means more, hotter means less) and many more that will determine what power you get, not only that dynos all read different. And before a mod says it there are plenty of results under the search function as well as check the dyno results in the FI area, then you can gather what you may or may not get or close to it, from the information that is listed.

Cheers Adam

[Cubes]

It has to do with the whole package.

The compressors ability to flow at the given pressure ratio and the turbine/hot sides ability to allow that air to flow out of the motor.

As you increase backpressure (smaller turbine housing and turbine wheel) you reduce volumetric effiency as less air is able to easily flow into the cylinders.

This is why bigger turbo's make more power on the same boost level, there's less back pressure so greater VE so more air flows in to the cylinder easier hence less boost required to make the same power.

[markimak]

i noticed on mine with stock turbo, 7 - 8 psi made 190kw and 11 - 12psi made 209kw. anything more than 12psi made bananas

bananas wouldbe worth alot 6months ago.

anyway.. thats because thats out of range for the standard turbo. it needs a bigger compressor housing. its creating far too much heat too.

[LTHLRB]

thats why i have ordered a highflow but im selling my car so blah

[RB SANDY]

on a std rb25 I would say about 5kw to 1 psi more boost