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whatever do u mean by basic.

If u want to run the power relaibly, i would suggest nothing over a 12.1 afr ratio, and maybe add a little toluene when u are gonna punish the car. THen the car should be fine. However if the car does run lean, it is very easy to crack ringlands which many forum members have lately. good luck.

Realistically how much power do you gain by running a 12:1 afr over a 11-11.5:1afr.

10-15rwkw?!? Bugger all.

The extra fuel helps things stay just that little bit cooler.

Keeping the combustion temps cooler prevents detonation (cracked ring lands).

I have no idea when it comes to tuning. From what I have seen the stock RB25DET's tend to crack ring lands up around the 250rwkw+ mark. If It was my car running that power I would ask for a slightly richer afr. 11-11.5:1

1 Bar is nothing for the stock internals even at stock CR, 265 is fine too. Merli was running more boost and more power with totally stock internals for some time without dramas.

It all depends on the tune, you can destroy stock internals with alot less than 265rwkw.

I would highly recommend you dont take any short cuts though, ie, do your injectors!

sounds good, make sure you have a good intercooler (no doubt you already have one), and good management. A conservative tune doesnt mean you wont have power. Hopefully your tuner will go for around 11.5/6 AFratios at peak torque, and 12s thereafter.

You wont know for sure until you get the turbo fitted and on the dyno for a tune - this seems to be where gremlins will raise their head in the first instance, then on the road, until you have them all ironed out. There are so many variables, it would be near impossible to highlight them all. I have found the issues I have had, others havent. and vice vesa.

Timing is another matter. If you have a power fc, you can actually make correction across the range when driving should you run into trouble. If you detect detonation on the street, just pull 1 deg of timing across the range, and monitor closely. I deg seems to make a huge difference to knock when you are at the threshold where the power fc starts to warn of problems.

I have managed to keep my engine in one peice with over 300kw on stock internals with just a head gasket to drop CR to 8.6:1 - but I am running around 1.5 bar and up to 1.7 bar regularly.

Best advice I can probably give is look at what they do in japan, then copy it exactly, without taking any shortcuts - they have been tuning these engines for so much longer than in Aust, and they tend to perfect things to a fine art. All the R&D has been done by them - with proven results.

What other mods have you got? what turbo are you running? what fuel are you using?

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