I have been trying to WOT tune for about 4 months and seem to never get anywhere... changed everything that has to do with PE from one extream to the other and everything in between. I was getting high end hesitation under WOT and figured it was in the tune. Now the other day I on a long haul home and decided to throw in some 93 octane at the pump. It did wonders for the WOT responce for the car... Last time I went to the track I ran 89 octane and ran mid 14's, but that was before the cam lobes rounded off and I put in the roller cam. I though the compression ratio was the only factor in what gas you should use. Yes, the cam is huge and in my opinion too large for the heads, but why is higher octane makeing WOT that much better with the same CR, which is slightly higher than stock, which I have always had?

 

TIMING.

there are a few other factors, like cumbustion chamber design, ect.

well compresion plays a major roll, you need to forget static compresion ratios, look at the dynamic compresion. the cam overlap ect will all effect the dynamic compression. example: with a big enough cam, 14:1 compresion will run on pump gas. because there is so much overlap, the effective compression ratio will be the same as a 9:1 engine with a small cam.

check you timing, and check the total timing commanded in the chip. if it is only happening at WOT, back the WOT Spark adder vs RPM values down. you might also back the timing in the 95 and 100 Kpa columbs down.

I also forgot to ask, do you have any knock when you log?

 

No knock at all, i tuned all that out and changed max knock retard, which helped a lot, but not enough.

I dont have a timeing mark anymore... so i kinda guess, and play with it a lot and set it per highest vaccume at idle and at cruseing highway.