I'm running 12.7:1 CR, knock happens no matter what. It's the bad kind of knock aka pre-ignition that worries me. The sensor is failing, and it cuts power to the car, it's annoying to drive, and I don't want to damage my $7k engine. I also don't have a way to set timing, I'm running the factory ECU.
12.7:1? What motor? Honda? That's a lot of compression out of a factory type gas motor. It can be done but you need to have the chambers polished and a lot of cooling. The knock sensor is probably not bad , it is probably reacting properly! Throw some e85 in there and see if you get your power back.
It's a K24 crank with custom rods and OEM pistons, knock sensor is failing, it always happens when you remove the transmission. I swapped the transmission after I did the clutch with the engine swap because the original transmission with 204k miles lost the 3rd gear synchro. So I must have damaged it during the install, it's common, just frustrated that I've been waiting on the knock sensor since the 10th of this month. I can't run corn syrup in my engine, injectors max out at 390cc but for corn I need 600cc injectors.
I am assuming it's part throttle pre ignion around the torque peek , the e85 will verify that is the case. Obviously can't do full throttle w it. But now that you said more info, we both know the results so unneeded.
Hondas have crazy compression. My real experience is tuning the big boys and keeping a 4.50 bore 12:1 alive on 91 pump gas.
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