Quote Originally Posted by Matt167
Because my dad lost low end power with the HEI he recently put in his '72 350, and it is backfiring through the carb more than ever, he bought a Advance timing light from HF and wants to check to make shure the curve is right. I googled for advance curve specs to set it at/ check for but no 2 are alike. what is a normal advance curve for an HEI?
you buy the curve kit you want, and all you can do with the adv. timing light is check for total timing. far as i know, to check to see what curve you have, you need to get someone thats set up to do that. i don't believe a adv. light will check the curve. the curve and how soon it comes in has more to do with racing than st. get your base timing, and check you total timing and thats all you need for the st. be sure the vac. adv. is working. backfiring sounds like its late in timing or running lean.