Spark plug heat range

[flattop1]

FYI.

 

[Dav]

Compression and cam intake valve closing. Head flow? My modified world formula picked 0.35 tenth’s on the local sprint track after 5 days of testing. I raised the compression 10.7 to 11.6. Wf cam to dynos mod 1 cam. This winter. Similar duration and lift. But closes intake valve alot earlier. And its a work out to pull start. The dynamic compression is high. But i want to try dyno’s 315, 310, and 356 cams. Mayb im to concerned with dynamic compression! And just choose one with more duration And spin it faster. 8000 to 8500. Without a dyno its a guessing game. Im not prepared to put a larger carb on it yet. I still need it to go from 4000 to 4200 out of two corners.

 

[Colt sr]

Compression and cam intake valve closing. Head flow? My modified world formula picked 0.35 tenth’s on the local sprint track after 5 days of testing. I raised the compression 10.7 to 11.6. Wf cam to dynos mod 1 cam. This winter. Similar duration and lift. But closes intake valve alot earlier. And its a work out to pull start. The dynamic compression is high. But i want to try dyno’s 315, 310, and 356 cams. Mayb im to concerned with dynamic compression! And just choose one with more duration And spin it faster. 8000 to 8500. Without a dyno its a guessing game. Im not prepared to put a larger carb on it yet. I still need it to go from 4000 to 4200 out of two corners.

With the mods you have on your engine and what you are wanting to try. I would be investing in a starter nut and a portable electric starter. Your arm and shoulder will thank you later.