Dark, light, brown, black, tan, white. Initially more influenced by air fuel ratio than heat range.

Make an educated guess as to what heat range you may need. (to get close) Dial in fueling, or at least get close.

Then look at jwb123 post, at least in reference to heat range.


69 Charger. 438ci Gen2 hemi. Flex fuel. Holley HP efi. 650rwhp @7250 510rwtq @5700