[Andrewyoung78]

My car has been running great but once in a while when I shut off, it pre-ignite?
There's no sign of pinging and what so ever. I only use chevron 92. I try to keep the fans running for cool down about a few minutes before I park to avoid the motor being too hot and my holley 770 set up to idle at 850ish.

Any idea why it does that sometime?