[DuDe]

I put my 4 barrel carb on. My 350 has its new hei distributor in and it is timed also.

So now when I stomp on my gas pedal it doesn't take off like I thought it would. It seems to be slower acceleration than my 2 barrel.

I have a 73 nova with 350. 600 cfm edelbrock carb.

any ideas?

 

[bowtie0069]

what intake? How much timing? Too little info. Most 2 bbl. intakes will make lots of torque down low, so it might feel a little soft at low rpm now depending on manifold selection.

 

[DuDe]

I am using an edelbrock performance intake.

 

[Gary and Matt]

I hate to say it, put we did the same thing when our 307 was still running. It worked OK.

Then the 307 died and we moved up to a modified 350. Then we had the same problem as you are having. Poor launch and driveability with partial throttle position. The only help I got from this board and other sources was to buy the metering rod kit and 'experiment'. Hell, I wanted to drive it, not jack around with the carb all summer! It ended up being a fiasco, so we dumped it, and got a 600cfm Holley with vacuum secondaries. It worked out of the box and only needed some mixture adjustments.

Good luck. Sorry I couldn't be of much help. Just thought you should know you're not alone.

Since then, I have heard the Demon carb's are better than the Holley, since they seem to be less sensitive to environmental conditions.

 

[SuperNova69]

Yeah, I had a Holley on my 283 and it ran great. Can't say the same about the Edelbrock on my 350, though. I've had it in a carburetor shop countless times, and I've even tried messing with it myself to no avail. I only wish I still had the Holley from the 283 to swap and experiment with, but I sold it to a friend.

Edelbrocks are supposed to be great right out of the box and hassle-free, but I've had horrible luck with them.

Matt

 

[DuDe]

. Im really dissapointed because I heard better about the edelbrock. I stomp on the pedal and it doesnt really pick up like with the 2 barrel. Im pretty dissapointed .

 

[Purple72]

I don't see how you can expect to bolt a new carb on have have it work perfectly right out of the box. With a 350 Chevy you stand a pretty good chance of that happening since it is a baseline engine for the aftermarket.

The Edelbrock is very easy to tune. Even those who have a running car with a bolt on carb got lucky. You can bet there is room for improvement if it were tuned. It won't take you all summer, the car will run better, and you will learn a lot if you take the time.

I spent the time and figured out how to tune a q-jet. That car runs great now, responsive, great top end pull, no stumbles, or bogs. It was definately worth the price of the tuning kit and a few hours of fiddling around. I am learning a Holley now(Demon 650) and it is much harder to figure out so far. It is a much cruder design than either the Edelbrock or a Q-jet. Stick with it, get it tuned

 

[Bucs01]

I seconed what Purple72 said. I have put Edelbrocks on my 70 Monte Carlo, 67 Chevelle and now (2) 500's on my 63 Nova Tunnel Ram. No problems at all. Fired up right out of the box but of course needed fine tuning to run just right.

Set the carb on the engine and see if it will fire up "out of the box" but bottom line is you'll still need to tune it in. I just adjust the idle and air/idle mixture screws with a vacuum guage, set idle screws, checked timing again and it's alway dialed right in with minor adjustments. Plugs have always been light golden brown.

 

[DuDe]

It started up when I bolted it on but of course I had to lower the idle and such. I have tuned the edelbrock as much as I can and it still doesn't have the power. Should I take it to a carberator shop and have them professionally tune it?


Thanks for all the replies.

 

[Bucs01]

You are 100% sure it is not your timing since you changed the distributor at the same time? Timing will dog you out like you're mentioning.

Do you have a vacuum guage to hook up while adjusting your carb? You can buy them at Autozone for like $15-$20. If this is a brand new carb right out of the box it should be pretty close and just need fine tuning.

Tell us about your timing. Initial, at 2,000, 2,500 and 3,000 and 3,500 rpms. What amount of timing do you have at each of these levels and at what RPM does it no longer advance?

 

[IgnitionMan]

Which "HEI"? If it is a Pro-Comp, take it out abnd throw it in the trash, go get a Pro-Form, stock GM, go back to points, anything else.

Initial timing is 10/12 deg/BTDC, yes? You did restrict the amount of degrees the vacuum advance gives, down to 8 crankshaft (pull pin travel set to .086, yes?), then connect it to full manifold vacuum, didn't you?

WHICH Edelbrock manifold? SOME of them, even if they have the correct carb base pad, need an Edelbrock 2732 plate to seal them to the carb. Use UNLIT propane around the base with the engine running, propane smell out the exhaust, engine cleans up, LEAK.

Also, send the Deadbroke carb back, Q-Jet works leaps and bounds better than an Edelbrock "Performer" AFB EVER WILL.

Demon = disaster. Not many people ever get the street Demons to work right, let alone close, as they don't have the tunability their "race" carbs have. The "techs" at BG really don't have a clue about most of the situations they misadvise as far as carb setup. BTW, Barney Grunt sues HOLLEY DOMINATOR carbs on his own Pro-Stock race car.

 

[misterjj]

Thought I'd bump this thread as I'm running into issues w/ my edelbrock 650.

Idles fine, drives find after 10mph, but it when I stomp on the gas, complete silence.

When I start from a red light I'm constantly worried I'll stall if I open it up too much so I have to crawl to a start then I can let loose. Drives me INSANE.

When I have it in park and idling, if i push open the throttle the same thing--it clicks and bogs. If I very slowly open up, it sounds find but I just can't stomp on the gas and get any kind of response.

Does this sound like a carb problem? Vaccuum problem? Timing problem?

 

[72GreenRally]

Your problem sounds like a bad accelerator pump. If you look down inside the carb, and open the throttle quickly, you should see some gas squirt inside. If you don't see the squirt, then get a new accelerator pump.

BTW, it is probably best to do this test with the engine OFF.