I've found that too-stiff springs that jack the rods up at idle do actually richen up the mixture. Doesn't make much sense, but that's been my experience with two different carbs.

I'd suggest switching to the 4" springs until you can get the idle and cruise mixtures dialed in, at which point you can probably switch back out to the 5" or 7" springs.

But yes, you do need to pick up a tune kit.

 

I was just reading the instructions on the edelbrock site and it looks like the fuel for the idle circuit is pulled through the main metering jets and rods which would make it too rich at idle if the rods are pulled up. I guess I'll be getting a kit when I get back from my road trip and get to tuning on it.

 

The other thing to look at is fuel pressure. Edelbrocks are very sensitive to high pressure and will behave exactly as you describe if the pressure is too high. Too high is anything over about 5.5 to 6.0 psi.

 

Well the timng thing helped a bunch. I checked it and it was at 12 with no vacuum advance. I bumped it up to 20 and thought that might be too high and it would ping. I don't have a fancy timing light so I could not tell what total was but it was off the charts. Went for a test dirve and it was running really good, no ping at all, good acceleration and I could actually keep it in drive when I came to a stop. The vacuum would drop to 4 but it would stay running. Before it would drop to 2 and just stall. The PO must have put one heck of a cam in that thing. I'm still going to get the tuner kit for that carb and change out the springs on the rods. I have to believe they are pulling up at idle since I only have 4 inches of vacuum but I'll run it awhile and see how she does.

 

Whooooaaaaa, 20* initial is waaaaaay too much, unless your mechanical advance isn't working. You may be pinging even if you can't hear it. Total should be 30-35* all in by 3k.

You really need to get the carb tuned properly. Set the idle higher if you need to in order to get it to idle smoothly, then adjust the idle mix screws. The higher idle should get it to pull enough vacuum to keep the rods down.

 

I'm tell you it is sitting at 20 and running great with no ping. I know the wild cams like a lot of advance and I thought the same thing until I drove it. Runs fantastic.

 

i have a feeling the timing marks on your balancer are out of whack. check them with a wire or piston stop.

 

Most likely the PO screwed up the distributor advance curves. I set up distributors, using a Sun machine, and I have yet to put one on the machine that turned out to be "in limits". Typically, the ones from performance models are the worst, from people messing with them trying to "improve" performance. Invariably, the opposite is true.