I know there's some sharp people in the group so I'd like to get some feedback on something I've been thinking about. The T/A is driving me nuts as it picks up power at the track the hotter the engine gets. I'm looking at timeslips and the car consistently picks up 2.5 to 3 mph if I hot lap the car. If the car sits for an hour or so it slows down and I go through the process again.
It's an aluminum headed 462 Pontiac with the deck height of -0.025. I run a
100 octane blend to reduce the chance of detonation with the cast pistons so far down in the cylinders. The static compression ratio is around 10.0:1. I pulled the plugs last week and they all seem to be running dark to me. I just had the car tuned on a dyno with a wideband O2 sensor so the engine shouldn't be running rich. Can too much octane cool the combustion chamber to the point of fouling the plugs? The car sees street traffic as well as time at the strip and runs well in both settings, idle vacuum is around 13.5 to 14.0 @ 950 rpm idle with a 255/265 @ 0.050 duration cam. I'm thinking of running the octane down to 95 and seeing what happens. I ran the car with new plugs at the track Saturday but haven't had a chance to pull one yet. If they are fouled again, I'll be leaning towards lowering the octane. Also, oil consumption isn't an issue, the rings are still tight, no smoke or blowby noticed yet.Dave