I Have A New Engine

[wheels_24]

Hi guys, i have just got my car back and i have just had my little Rb20 rebuilt. I have basical done a standard rebuild top and bottom but have thrown in some 40thou over aries forgies to be on the safe side, as i got them at a good price. I was wondering after i have finished running my engine in what sort of boost would be ok to run at and the power that i should get from it. These are my support mods: HKS FMIC, bosch 040, adjustable fuel reg, bigger injectors i think about 440cc not sure on that, wolf 3D, POD, 45 external gate, 3" exhaust turbo back, all 3" piping from FMIC if that matters and a GT30 ballbearing rated at 550bhp+ so the guy told me that gave it to me.

Yer so if anyone has any ideas what sort of boost levels would be ok that would be great thanks

Edited September 29, 2005 by wheels_24

[wheels_24]

Anyone! any help would be good just after some personal thoughts on it i have had a couple of different tuners tell me different things thats all

[Cubes]

What static comp ratio did you end up with?

The stock 8.5:1?

Providing you have the required support mods, fmic and turbo to support such boost levels I would look at 20-25psi.

As I said thats providing the turbo is efficient at those boost levels and the fmic can handle the flow and charge temps.

I would tend to run the higher boost levels on the street and a less highly strung boost level for the track. As really, on the street its only quick bursts of power not big long 4th gear windouts.

Edited September 30, 2005 by Cubes

[CEF11E]

Not knowing what your turbo will push out at 20+ psi,

My dad once said to me "an engine is only as strong as the weakest part"

in this case i think it is going to be your con rods.

I think 250RWKW is safe for RB20 rods. Also pushing that thru a standard RB20 plenum and head is reaching its limits. the motor if properly built will handle the boost pressure required to make this power figure.

[Mandingo]

Your injectors will run out before you can run max boost anyway.

I'd start low then leave it at 12 to 14, that should be enough for the street.

I take it there GTR injectors? if so there good for around 300KW

Edited October 1, 2005 by Flipmo

[Cubes]

Also pushing that thru a standard RB20 plenum and head is reaching its limits.

<{POST_SNAPBACK}>

Nothing wrong with the stock plenum.

They handle up to 300rwkw without issues.

The RB20DET plenum is exactly the same as the RB25DE plenum, the rb25 inlet manifold does however have slightly larger ports.

The stock exhaust manifold becomes an issue before the plenum does.

Edited October 1, 2005 by Cubes

[wheels_24]

thanks guys for the feedback not sure on the ratios will ask the guy that built then engine for me i was thinking of running about 18psi to be safe

[wheels_24]

me again i talked to the guy that biult my engine it seems that my comp. was 8/3/1 not sure if this is good or not i think standard it 8/5/1 not sure is it better to have lower comp.