well I wrapped the header on my 12asp and now it pops and carrys on I ahve a holley 650 double pumper low range sucks and high range is feeling lean I have 67s jets in the front and 76sjets in the back should i go to a bigger jet to compensate for running cooler?

 

I take it by wrapping you mean you wrapped the header with some sort of heat shield blanket thing. If you did the popping is likely due to the fact that the exhaust gasses aren't cooling that much since you insulated the header. Basically the left over gas is still combusting when it leaves the exhaust. IMO. I would try leaning it out some to see what it will do. if it was already too lean it prolly wouldn't pop since most of the gas has been combusted already. Make sense?

anyways i saw you sig, what kind of tranny/transfer case are you using. Sounds like a pretty cool combo. haha do you off road it or anything I can't imagine it being that good with such a high torque curve.

 

that extra heat is helping your exhaust flow, but killing your headers. try going to a smaller air bleed to richen up the top end a little.

carl.

 

79 mazda trans to samurai tcase yeah I wheel it but the carb sucks off road .also I put in 5.13 gears to make up for low end its great I can pull up to a mustang gt and smoke his *** or I can pull up to a v8 jeep and tear him up on the trail. thanks carl I will try it