I have been having a little problem with my RB30DE motor in the hot weather. This started when I got another ECU for it (it runs an R33 RB25DE ECU) and I had it set up to the standard base ignition timing setup that the RB engines run on (i.e. 15 degrees BTDC),it didn't do it with the first ECU as it had a problem where it wouldn't read any voltage from the AFM,causing it to run rich,foul plugs and cut out at 2000 RPM. Last night I set the ignition timing up so it was retarded by 5 degrees (i.e. 10 degrees BTDC) but the VVT unit advances the inlet cam by 5 degrees above idle,before it advanced it to 20 degrees BTDC above the base setting of 15 degrees,it now advances to 15 degrees above idle from the base setting of 10 degrees. I run SHell Optimax on with it and I had to advance the valve timing by 1 tooth so I could pick up enough scope to adjust the ignition timing,previously the ignition timing was set at 0 degrees and the most I could go was 10 degrees BTDC even though all of the timing marks on both cams lined up to the marks on the cam covers and crankshaft pulley. The motor in the night time pulled well and didn't ping,today it pulled o.k. but pinged under load and it was hot up my way,it pinged less with more fuel in the tank but there was still half a tank of fuel left before I topped up. Could colder plugs fix the problem?,I could go down to 5 degrees BTDC which may even free up some more power but I am not sure whether it will stop it from pinging,if this helps the motor runs a 10.5:1 compression ratio and it would be great to stop it from pinging as this affects the performance a little by dropping the torque.

10.5 compression....... id avoid optimax, as from what ive been told it has a very limited shelf-life compared to other fuels. give synergy 8000, or bp ultimate a shot. i know personally my car will ping sometimes on optimax but never on synergy or bp ultimate