So as the title says its pinging at acceleration, worse on hot days. I run 93 octane, and still does it. Also at lk 4500 it begins to break up. Feels like its missing.

I have adjusted the timing everywhere from 36 total to 28 total and still does it. Also the dizzy is recurved with lighest springs. Dizzy is only lk 3 years old.

Plugs were pretty white (lean condition) so I richened up my carb.

Carb is edelbrock 600 (1406) which i read is lean from factory so I put the richest metering rods in. Maybe helped a little but didn't cure it.

Changed fuel filter, maybe helped a little, but not fixed.

12cc dished pistons and 68cc chambers IIRC. The compression ratio is right around 9.4:1.

I'm stumped, any help guys?

 

hows and what kind/size wires are you running? are they in good shape? have you took a multimeter and ohm'd them? i have 383 with same carb, had accell brand new wires on it that were no good cause the samew thing, in higher rpms and plug wires were breaking down, causing ping and the miss of course, got me a set of 8.5 msd streetwires and no more worries, even header heat dont phase these things......also carb has internal jet screws that are changable if your running rich or lean reasearch edelbrock calibration kits....

 

The wires are 8mm Accel wires. They are fairly old, about 5 years. They appear to be in ok shape, but inside might not be in good shape. I'm goin to test them with my multimeter soon.

I actually have the calibration kit. Have you tuned yours? any idea of what the ideal jet/rod combination is for a mild 383?

 

What fuel pump are you using? have you checked pressure at high RPM with a mechanical gauge?

FWIW I had the same exact problem and it progressively got worse until it didn't do anything but ping and choke over 3k RPM. It was the mechanical fuel pump dieing.

 

Just got done testing the wires. The lowest reading was 7,000 ohms on the shortest wire. The highest reading was 15,700 ohms on a real long wire. All the others were right around 11 or 12. According to the little info I know these numbers are pretty normal right?

The fuel pump is just a stock replacement (mechanical) it's about 2 years old.

Oh yea, before I replaced the fuel filter I was listening to the carb as i gave it quick revs by hand, and it sounded odd to me. You know how you can hear the fuel being squirted? well when i cracked the throttle it was not a solid, constant, clear squirting sound. It was kind of spitting and did not sould like a clear path of flowing liquid should. dunno if this helps.

I think the mechanical guage is next on the list.

 

I just recieved my fuel pressure Pressure Tester kit from summit.

http://www.summitracing.com/parts/SUN-CP7818/

However, the guy who I talked to obviously didn't know what he was talking about because he said I could use the clear line to attach to my fuel line, but the directions say its a bleed off.

How should I go about plumbing this thing, I need to run it into the cabin so I can monitor the pressure at throttle.

 

Most recommend plumbing it into the fuel line and taping it to the windshield.

I have the same gauge but I've never used it on anything but FI. Hopefully someone knows how to get it working for you. Maybe get the guy on the phone who sold it to ya?

 

Alright so I ended up getting the right guage and found as I hit wide open throttle the fuel psi dropped to about 3.5 psi... too low.

So this means, as Doom86 said, that my fuel pump is on its way out? I'm thinking yes.

Advance has a holley similar, if not this one.
http://www.summitracing.com/parts/HLY-12-834/

Do I need a return fuel line?

 

I believe the return line is for fuel injection. With the carb you just get a fpr to meter your fuel needs.

 

So should I just cap off the return line? I have 3 lines on my fuel pump. You only need a regulator on the really high flowing pumps though right?

 

You'll only need 5 to 6 psi for normal driving. Good place to start anyway. Too much fuel will cause it to run rich or even flood. Gas is to expensive to waste. IMO.

 

Well seems the fuel pump fixed it.

Thanks for the help guys.