1965 Mustang Backfire

[joemac1000]

Hi!

I am new to Stangenet.com. I am new to the automative field and learning as the time passes on. I have acquired a 1965 mustang coupe Code C. Since then I have invested a lot of money into the engine and body. To make this story short, I have a backfire problem (popping in my carb) . I have a 1966 289 block with 1972 ford heads with screw in studs. I have installed a 600 cfm carb (edelbrok) with a drop in MSD distibutor. I used my orginal rockers (1965) and push rods on the 1972 heads that I aquired which were recently rebuilt. When I start my engine, I have a immediate start but as soon as I increase the throttle, I backfire or (pop) out of my Carb. I have tried to adjust the timing which I have moved back and forward one tooth which did not help. I tried to adjust the rocker arms but do not know if that is the problem since all of them are tight but not too tight between the pushrod and valve spring. I have tried to adjust the carb air/fuel intake raito but does not help. The popping starts when I increase the thottle quickly but as soon as I keep the throttle at full it stops with the occasional pop. Can anyone help me with my dialima? Once again I have tried everything and lost.

Thank you for any help you can provide!!!

 

[57fairlane]

probably a timing issue. You really should check it with a light.

Typically a severly retarded timing setup.
But usually it wouldn't start right away very well when its cold. Also, the motor will run cooler but unless you have a gauge this probably won't matter.

 

[Cannoball888]

Do what 57fairlane said. I had a similar problem with hesitation and occasional pops through the carb. After advancing my timing the problem was gone.