Now I can do some street tuning and play with the timing.
I used "Afrotechmods" video on op amps to build it. If you want to build one here are a few tips for this application. You don't need to power the knock sensor so omit that part. Also since you aren't powering it the filter part can be removed. (The 0.1 uf cap and 100k resistor.) The knock sensor has a chassis ground and signal pin. The knock sensor ground goes to the 9v battery ground setup in the video. For the gain resistors just omit the second one. That sets the gain to max. In the video the second one I'm talking about goes from signal output to inverting - in.