Forum » General Tuning Discussion » Rb25 boost

Rb25 boost

General Tuning Discussion

Discuss all things tuning in this section. News, products, problems and results. 

Page 1

Hey guys ive built an rb25 engine from an r33. I used wossner forged pistons and pec rods. It has stock compression ratio, solid lifter conversion and running hks 256/264 cams, inlet vct is still functional. The car has 2x bosch 044 pumps, twin feed rail and id1300x2 injectors. Turbo is a 6062 gen2 precision. The car will be used for drifting. It is running on e70 fuel mix. Can anyone advise a rough target for max boost pressure?

It's a difficult question to answer as the boost will come down to your power targets and the way the engine will be used. For drifting you have the advantage that the engine is generally only under heavy load for the judged section and hence this is a relatively short time but boost and power generate heat and this needs to be managed.

The 6062 is a 750 hp turbo but sadly we don't get compressor maps for these turbos which isn't overly helpful. If you want the most out of the turbo you're probably going to need to be running in the vicinity of 30+ psi however this may be a touch high for long term reliability. I'd personally be aiming for a slightly more conservative boost level in the mid 20's which should provide a good mix between reliability and power. Ultimately only you can decide where you are comfortable on this scale though.