1FastS2k

So, I've been getting some pinging that sounds exactly like detonation. Usually only happens in high heat, most noticeable when I'm on the highway and throttle is applied. I have a wideband and it does it under light load and when under the WOT map. I threw a bottle of Torco Fuel Accelerator in on our last group drive and everything was fine on that entire tank. Problem came back on the next tank. Apparently it is octane related? New plugs and valve adjustment have been done along with an ecu reset, but the problem persists. I drive in AZ/NV/CA so we only get 91 octane out here.

Some background on the car:

The motor is an 03 with roughly 100k on it. Mugen intake, Toda header, Spoon radiator, Mugen rad/fan/thermostat, Invidia TP, and HKS single. I've never had this issue during the winter time, but during that time, I usually run the Mugen ecu with a bottle of the Torco Fuel Accelerator effectively bumping the octane up to 93-95.

Any thoughts on this? Its kinda been driving me nuts as I can hear it, but no CEL.

1FastS2k

Any thought, comments, or suggestions?