The Stovebolt Site Forums The Shop Area General Truck Talk Edlebrock

I've been having a real bad experience with a Edlebrock carb. Poor performance, rotten milage just plain unhappy with it. I've heard a lot of mixed feelings about them. Anyone care to give some input? I'm quit willing to through the money out the window and call it a bad experience but I keep asking myself, "Why'd I buy this thing? I thought they were bullet proof."

Fat: What is it doing, I run 3 Edelbrock's, 1 on 318 (500) 1 on our race car (650) and I have a 750 for the 59 might change my mind on that and go a different route. We have got years service out of ours. You might be trying to run to big cfm's on your application.

popcorn The Truth is Out There (The only thing I have heard is a choke problem now and then)

I,ve been running them lately with great sucsess.Although I,ve always been a Q-jet fan.
Do you have a filter in front of it? Maybe you
are getting dirt in the needle & seats. How about
the timeing? Do you set it with the vacuum line
disconected? :confused:

It's burning so rich that people travelling behind me are afraid to light up their cigarettes. I picked up a calibration kit and so far have the largest metering rods and smallest jets. I'd hesitate to say I'm getting about 8 mpg, the tail pipes are blacker than coal, electric choke that is functioning correctly. Running a 305 with a TH400 and 3:35 gears on a Fjord 9" - timings +12 deg with vacuum off and plugged, MSD ignition. Not that I want to burn rubber but this ol' thing won't even chirp the tires. Oh it's a 51 Chev 1/2 ton with a 30 gal tank behind the wheels (for traction - lol)

What's the manifold vacuum at cruise speed and light throttle? You might need lighter springs under the metering rod pistons, or maybe just a carburetor with a lower CFM rating. If the throttle plates and venturis are too big, the vacuum drops drastically every time the throttle is opened, and the metering rods go to the full-rich position. You'd be better off by far with a stock-calibration Quadrajet. It was designed for the 305, and other GM engines, and there should be plenty of correctly set up carbs available. The Edelbrock is a generic replacement unit, and unless you've got a flow bench, it's going to be difficult to get an exact match.
Jerry

I have two Quadra jets ... not sure which one to use ... one came off a 350 (Corvette) he said his machine ran like stink .. but there's a lot off holes, pipes and such that should be filled up and I don't know which ones to block or which ones to leave open.

For the 305, you really dont want to go over 600cfm, which would be the Edelbrock 1405 (manual choke), or 1406 (electric choke). And those are for the square bore performer carbs. I bought an Edelbrock 1405 600cfm, and it works great. I almost got a 750cfm for my 305, until I was told by many people that its too small of a motor to handle it.

Also, what are the numbers on your quadra jets carbs, i can look them up and see how many cfm's they are.

- Shane

My Edlebrock is a 1406 (electric choke). I've got the Q Jet sitting on my lap in front of the 'puter where'd I find the number on it?

Fatfenders, great thread.... I had an edelbroke 1406 w/electric choke that did the same thing yours is doing... I sold it on ebay...

I've got another one on The Ox now, it gets a little better gas mileage (11 mpg or so) but still not what it should be. It also backfires occasionally when it is cold and I floor it.

An Edelbrock 600 is designed up for use on typical V-8's like you have.If it's too rich ,it was bad out of the box,fairly unlikely. More likely,engine vacuum is not pulling down the metering rod pistons into the light load position or the float needle leaks.
With the engine warm and at idle, loosen the screw on small cover for the metering rod piston, the piston should be in the down position, if it pops up when you slide the cover aside, there's your problem.

RR - when I floor mine is sounds wicked but it doesn't do much ... just sounds great ... lol ... occasional backfires when it's cold ... I was wondering if the float is set to high and I'm just plain pushing gas ...

Trucked ... this is the stuff that this page is for and thanks - I'm out there now ... back in a few minutes ...

Backfire out the carb when cold is cause of leaness,wait till it warms up before beating on it
I'm no big fan of the Edelbrocks, but they are pretty much a copy of the Carter AFB,which is an ok carb when used on the applications it's designed for..
Q jets are ok too, but they suffer from a rich idle sometimes.The small primaries have ya dipping into the secondaires whenever ya need some power. Guys like the big surge of power that comes from opening the secondaries,but that's just a bog,the power should build smoothly and evenly without any "surge"

Shoot! It'll have to wait 'til after the race.

Had a 1406 on a stock 84 GMC and it ran great. After that motor blew I put it on a reasonably built 350 and it still ran great.

Fatfenders, the part number on a Q-jet is on the driver's side, near the secondary throttle linkage. it will be about an 8-digit number probably beginning with 1705- - - -, or possibly some other 4-digit sequence that indicates the general year of manufgacture, followed by another series of digits that tell what it was originally calibrated to fit. Since these carbs might have been installed on any size engine from a Pontiac 230 overhead-cam inline 6-cylinder to a 500 cubic inch Cadillac, there are lots of different jetting and metering rod combinations. My reference books are 80 miles away, but I'd be glad to check it out in a day or two.
Jerry

Well I just did something that I have been holding off 'cause I knew it was going to be bad. I did the math for milage ... 3 mpg ... 3 good God I knew it was bad but 3 - jumpin' jehosifats ... It's like there's no jets ... a 1/4" hole would be about right ... oh and by the way this is the second carb as the other one was shot inside. I think I may replace the carb with a garden hose ...

3 MPG? Don't blame the brand, you've got something really FUBARed - junk under the needle, sunk float, missing parts, related engine troubles, etc. Maybe you should look at it like this: "As fouled up as thing is, it's still running - that's bulletproof!" Fix it.