I installed an Edelbrock 1406 (600 cfm, elctronic choke) on my 72 grabber after having problems with the old carb. After getting gas to the carb it started right up. It idled a little high but after messing with the lean/rich screws we seemed to bring it down some. And it idled pretty smooth. My problem is, when I take it driving, if I give it more than a little gas, it will bog and I'll hear a spitting sound coming from the carb and if I stay in the gas, it will stall. If I let off right away it will stay running but with no power. Sometimes, i can baby it and get it past that point (25-30 mph) and it will seems to run ok after that. At idle, if I give it gas, I can hear it bog, but no stall. But when it revs back down, I'll hear some backfiring from the exhaust. Ive tried to adjust the mixture screws both ways. Lean....rich...same thing either way. Also I want to say thanks to 9mpg for all his helpful info and advice!
The mixture screws only adjust idle air/fuel mixture. Is this carbn New? Is the vacuum advance hooked up to the correct port on the front of the carb? With the ca off can you pump the throttle and see the accelerator squirt fuel? A 1406 should run out of the box pretty decent on a 302. But it will be a bit rich. These are tuned for a 350 at the factory and to get it right on most anything you may need to get a jet and rod kit to fine tune it.
Rebuilt by edelbrock. I have the vacuum line hooked up to the passenger side port on the front. I havent checked to see for fuel when the car is off. Just assumed it was getting fuel because it starts right up and idles pretty good
Not sure if an Edelbrock is anthing like a Holley but, when we used to do the circle track thing, a backfire through the Holley carb usually meant we had to replace the power valve because the backfire blew it out
I had mine hooked to the drivers side port and it ran great, when I hooked it to the passenger side port it ran like crap couldn't even get it to idle. If I remember correctly the passenger side only pulls vaccuum with the throttle plates open try switching the and see what happens. Also have you checked your timing?
This is easy enough to try. Have not checked the timing yet. On my list tonight. Would replacing the carb, have an effect on timing?
edelbrocks/rochesters have no power valve circuit to blow out. and the poster above has you headed in the right direction. Initial timing is probably off to begin with and the disty's vac pot is likely hooked to a ported vacuum signal(which only increases as airflow through the carb increases significantly.. not the manifold vacuum which the disty needs to advance timing once the engine is at idle. Look at the schematic of the Eddy and you can see where you need to be. PS. once you get timing jacked up at idle where the motor likes it.. you'll probably have a high idle and likely need to back off the throttle plate a bit to drop it down where you want it. I usually figure out where the motor likes to idle once the auto trans has loaded it and then set my no-load idle to that just for tuning purposes. Then adjust it back up a bit for your no-load idle speed. 200-300rpm is usually ballpark for what amount the trans pulls the idle down.
Yes a tuning pamphlet, I went through it and it didnt describe my condition exactly but under bogs it says vacuum leaks or too lean or too rich. Now that I think about it. When the old carb came off, it was mounted on a 1 inch spacer (Made by Gasket) I went ahead and mounted the Edelbrock on the spacer. I put a gasket between the manifold and the spacer and another gasket between the carb and the spacer. Is there an advantage to having the spacer or is it just another area where a vacuum leak could be?
Is there a section about the spring, and rods in the carb? I had one, I didn't like it, and went back to a Holley.
I ran the port on the back to the transmission. Mine ran better, and really liked, the vacuum advance port that had vacuum all the time. It would run on the correct port, but it was really happy with the full-time vacuum. On my original low compression engine. Not so much on my 5.0 with 9.5:1. By then, it ran way too lean and I started using holley double pump carbs, 600 first, then 750 before I could get it to run where it wanted to.
