Howdy y'all..my t/a has been problem after problem..
Has a 305, eddy performer rpm intake, point type dizzy, holley 600 vac secondary, inverted long tube headers..factory cam, tpi heads.
She will fire and idle fine, and I could drive her around, but around 3500-4000 rpm+ she pops out the exhaust real bad and flames shoot out. Flames to be expected with just headers..its the popping that I'm concerned about. That and my header on pass side getting red hot after 2 mins running from cold start.

I'm unsure what my timing is currently set at, I believe to be 20-23* base. Retarding and advancing the timing doesn't affect anything, still pops. Double checked all my plug wires are right and tight. Dizzy is entirely new as well, everything good condition.

I also just re adjusted all my valves, all are opening and closing fully. Motor has 36k original miles.
New intake gasket, carb gaskets.. no leaks there.
Just today it flamed out the carb (99% chance of blown power valve now), but everything I said was happening before that happened. My carb also has no choke, elec fuel pump putting 6psi.

Not sure where else to go from here..

 

does your exhaust smell real rich? sometimes running rich can make headers glow as the fuel is igniting in the hot headers.

i've always heard with open headers you should bolt a length of pipe on, spray paint a line on the pipe, start the car and let it run a few minutes. where the paint stops burning off, is where to cut the pipe. something to do with flow or scavaging. maybe somebody can explain it better?

i'd throw a timing light on there and verify the timing. check the total advance too.
why not run an HEI dizzy?
do you have vacuum advance? if so hook it up to full manifold vacuum, it will run a lil cooler.

just tossing out a few ideas.

 

To repeat what Joe has suggested, sounds like timing. Having checked it, do you know what it is around 3000 rpm? Do you have vacuum advance? The points distributor is suspect too unless you know how to set them up with the cortrect dwell time and how that dwell affects timing.
Yes, open headers right at the collector can cause all sorts of odd things to happen. The extended colllector as Joe had alluded too is for just the reason he states. Collector length directly affects the "tune" that's put into the exhaust. Although there's more to it than what Joe describes (the old racer's trick for establishing the correct collector length) any length of pipe on there will change how your car reacts.
The popping in the exhaust is unburnt fuel being ignited by the hot exhaust gas. An overly rich mixture combined with late ignition timing is a sure recipe for what you describe. (But I stll say gets some pipes on it befor you proceed).

 

I have some pipes I've been throwing on, and found the issue.
She was burning real lean.
I discovered my secondaries were opening, but not actually spraying anything, made her burn real lean at high rpm.. threw on a buddys confirmed good carb, she red lined with no popping and only flame when I backed off throttle.

 

nice to hear you found the problem