sorry man, I don't know anything about P28, all i know how to chip is obd0 (PM6) make a post in the engine management section, and read some more about chipping, it's actually really easy to do it yourself, you seem like a smart person, i bet you could do it.

 

So if the ECU is retarding the timing at high boost, it would be best if I retard the timing by a modest amount...6 degrees from stock which is 16 degrees BTDC. So, when the ECU advance the timing in low boost, the increase will be cancelled by the amount it is retarded in high boost. Is my assessment a good one?

 

Spencer, thanks again for the feedback. I will do some more reading.

 

i am about to chip my P28, so if you want i can tell you what to get and how to do it, but remember it is my first time.

 

Thanks man.

 

I just retarded my cam gear 3*.Havent had a problem with detonation yet

 

I don't think retarding the cam gear will affect detonation. Advancing or retarding the cam gear will only affect the power output. Retarding the cam gear will reduce low down power but it ncrease top end speed...advancing the cam gear is the opposite .