Ive got a few questions for you all. I have a 429 that I recently put in my 77 F150 4x4 w/ a C6 and an NP205. The engine is mildly built, and everything on it is brand new, with less than 600 miles on it total. I have a mild cam ( i can't remember specs of hand, but it is a performance range 2 cam ) and a 600 cfm edelbrock performer carb. The carb has a jet one stage richer than stock along with matching rods. I am new to tuning this carb and may need some help.

My first question.... What should the timing be at on the engine?

Second, I am having a problem with the carburator I think. When I leave a stoplight or exit a sharp corner and let on the gas after idling for a little while, sometimes the engine seems to sputter and miss. This seems to be only after it is warmed up. Sometimes it even backfires. I have tried adjusting my mixture screws on the carb, and they do not seem to make a difference in this case. Any thoughts? Should I just bring it to someone who knows how to tune this carb and have him do the tuning?


A week ago, I had a problem with my truck seeming to miss very badly after driving for a while. We attributed this to the arcing of the plug wires, and a crack in the base of the distributor cap. I thus replaced my ignition w/ accel wires, new plugs, distributor cap base, ignition module, and I also have a fairly new coil. Any help would be appreciated.

 

Sounds like your timing is off. It sputters when you nail on the gas? and it backfires? Ummm, does it backfire consistently..? Backfiring through the carburator usually indicates a timing problem.
I'd say it's Either carburation or timing. Since you just replaced your plugs, wires, cap, etc., I doubt it's any of those.. your ignition sounds to be in fine shape.
To tune an Edelbrock, you must change out the metering rods in the top of the carburator. There will be little plates with Star Head screws in them (should be, anyway) and under them will be L-shaped metering rods.
Check your plugs. if they are covered in dry, black, sooty looking fouling, you are running rich. You need to get leaner metering rods. If they are chalky and white, you are running lean. You need to get Richer metering rods. Ideally, they should be light tannish color, with no heavy fouling or residue.

First of all, though, check your timing. It should be set between 8 and 10 degrees BTDC..

J/.c

1965 Ford Galaxie 500 (okay, so not quite a truck)
ANOTHER 460/C6 @ 365hp/519 lb.ft.
14.36@100.4, 16-18 mpg AHHAAAHAAAHAAA!

 

This morning I drove the truck to school and my problems happened very badly. After it warmed up, my problem occured, it seems like it happened when the rpm dropped. After I slowed down for a car in front of me, I got back on the gas and it started missing and then simply quit completely. I was able to pull into a parking space, and start it back up again. I noticed that my headlights were very dim, and looked at my voltmeter, it was reading around 10.5 even while reving it (the headlights became brighter) it only went up to 12.5 I made it about 2 miles down the road and it happened again, same situation, but I was able to keep it running barely. I finally made it down to a gas station and filled up. It seemed to run very well until I got to school, 20 minutes later. Those twenty minutes were in very slow stop and go traffic. When I got into school, it died, I restarted it, and drove into a parking space. Mid way through fiddling with the carburator, it died out of the blue again, very suddenly. Do any of you all have any ideas. I am at a loss.

My timing is at 6 degrees btdc. My entire ignition system is almost brand new. I recently replaced my voltage regulator as well, and all of the wiring is new.

 

Check all your electrical connections, including grounds, and primary wiring. For your lights to dim like that, it sounds like you have a major, intermittant short. These problems are no fun and the only way to correct them is to methodically check each wire and the connections. It could be something as simple as a loose headlight wire.

I've used the Edlebrock 600 and 750 on several 460s. For stock or mildly modified engines, in almost every case they perform (no pun intended) best right out of the box. I have most of the jets/metering rods and for mild engines always end up back at base jets/rods. The exception is the 750, which likes the non-electric choke jet/rod configuration.

If it's stumbling on initial normal operating temp acceleration, you need to check the step-up springs on the metering rods. There are four different springs available and Edlebrock recommends starting with the strongest to determine if that's your problem. Then back down in spring tension until you find what works for you. Sometimes changing the accelerator pump arm position will cure this problem, but in my experience its always the springs.

 

Did you check your vacuum advance it may not be working properly
also check your mechanical advance and timing should be at 10 dergees

 

I would remove the alternator and take it to a local parts supplier and have it tested. It probably won't cost you anything to have it tested and that would be a great start instead of spending numerous hours tracking down wiring. Furthermore, you may want to check your battery cables. I have seen where a loose cable (especially the ground cable to the block) can cause the symptoms you are describing. Hope that helps.

TBirdGuy

"Stuck with a m*par, Settle for a ch*vy, Happy with a Ford!!!!"