View Full Version : Stupid Edelbrock

03/18/06, 08:35 PM
Okay, I Give Up. I Bought My Bronco. I Have No Idea What's In The Motor. Guessing Rv Cam/ Mild Rebuild. It Has An Edelbrock Intake And Carb. My Problem Is The Carb Sucks. The Thing Has Stalled Going From Neutral To Drive When I Was In Low. Yes, It's That Bad. The Plugs Look Good And It Starts Right Up. Getting Tired Of Taking Little Bumps And Stalling Or Avoiding Obstacles That I Know I Should Be Able To Do Because I Know It Will Stall. The Only Way I Can Wheel It Is If I Get The Rpm Over 1000 And Hold The Brake To Ensure It Doesn't Stall. Get's Exhausting. Got A Few ????

1. How Do I Tell What Cfm The Carb Is?

2. What Came Stock On A 302?

3. I Bought The Off-road Needle And Seats. What Else Should I Do? I.e. Float Level Or Fuel Pressure Regulator?

4. Should I Just Not Worry About It, Until I Can Go Efi?

Duke Nukem
03/18/06, 09:19 PM
What is the model number of your Edelbrock? It should be stamped on the front. The most common I see are 600 cfm, which is a bit more than a 302 needs but can be set up to run just fine. The offroad needles and seats won't help much. The edelbrock is a great steet carb but it has a tendency to starve/flood when offroading. One thing some people have done is to block off the channel that runs along the back of the carb to keep the fuel from sloshing around between the fuel bowls. Someone did a writeup on that that also included changing the float levels and using a fuel pressure regulator and had good results. I'm at a loss to remember where I saw it but perhaps a search on this site might turn something up.

03/18/06, 09:31 PM
I'm having the same problem with the 600 Edelbrock on my rig.
I thought it was the vacuum advance on the dizzy but now I'm sure it is the carb..
It lugs climbing inclines, Pops when I mash the throttle, and surges when I WOT..

I may swap it out for the 1650 Holley I have in storage.

03/18/06, 09:40 PM
Throw the edelbrock away and buy holley truck avenger. I had same problem with mine always sputtered and flooded out on inclines finally junked it and bought holley. Never looked back. And no dont ignore it and wait for EFI. Carbs are just fine if set up right.

Duke Nukem
03/18/06, 11:24 PM
OK, I found the information I was looking for on the edelbrock. This info was plagiarized from Pirate4x4 but I'll summarize the steps you should do here. Before you toss your carb you should try the following steps first:

Step 1
Install the offroad needle and seats.

Step 2
Install a fuel pressure regulator. Start by setting it to 2-3 psi. You may need to play with this setting depending on your particular engine.

Step 3
Adjust the floats. Factory settings are best for street use. With the hat off of the carb, lay the assembly upside down. Measure from the edge of the float to the base of the hat. Bend float arm until you get somewhere between 1/2 to 5/8 inches. Again, you may need to fine tune for your specific engine. Make sure you do not press the needle down into the seat. You can use a flathead screw driver under the float arm to keep tension off of the needle/seat during bending. You can also use a bolt or drill bit as a ghetto measurement tool. (see first picture)

Step 4
Block off the rear channel between the fuel bowls. This channel allows one bowl to flood the other if you are off-camber. The best way to block this channel off is with a short piece of hose. Make sure the piece is big enough to block off the entire channel but small enough so that the carb assembly can be bolted back together. (see second picture)

Step 5
Set the float drop at 1.25 inches. There will is a small tab on the back of the float arm that you can bend to adjust the float drop. (see third picture)

03/19/06, 11:15 AM
The Only # I See Is 406 1151. Is That What I'm Looking For?

03/19/06, 11:38 AM
Whats your idle RPM's set at? try turning the idle speed up if its below 800 rpm when in drive.
Lowering the floats and blocking the channel should help your offroad performance. Thats pretty much all you can do besides buy a holley I wouldnt but a TA just get a regular holley and see my tech article it will save you about $200

03/19/06, 12:42 PM
Make the mods that are mentioned above and you won't have any problems. I have been running Edelbrock carbs for over 15 years on my Broncos and have not had any problems.

03/19/06, 12:46 PM
I'm in the middle of doing that carb upgrade on a carter 625(same as edelbrock performer) off our 66. I figured we'd give that a shot. If it still works bad she gets a q-jet like my 72. The q-jet works great but she has less hood clearance for the taller set up. I'm also working on a lower set-up for the q-jet using an offy manifold.

03/19/06, 01:45 PM
Done everything that has been thought of to my Edelbrock to littles satisfaction. Switched to a Q jet from BC and couldn't be happier.

03/20/06, 07:17 PM
Well This Is Helping. I Had Read The Article On Pirate Before Just Forgot About It. That's Where I Heard About The Off-road Needle And Seats. Already Adjusted My Foalts The Same Way. I Have A 500cfm Holley On The Way From A Freind. But It Looks Like I Definately Need To Get A Pressure Regulator. If I'm Not Satisfied W/ The Holley. Maybe I'll Try The Bc Q-jet.

03/20/06, 08:20 PM
My edlebrock is out the door. Where is the best place to get the Q Jet? Sorry for the hijack.

03/20/06, 09:46 PM

06/16/06, 05:55 AM
Who sells the offroad needle setup??

06/16/06, 12:08 PM
Who sells the offroad needle setup??
Try Summit (

Here's the original Pirate article Carb Mod (

06/16/06, 01:48 PM
Before running out and getting the offroad needle and seat make sure it isn't already there. Carters didn't have them but most of the Edlebrocks did so buying them may be a waste of money.

FWIW, Before Quadrajets became common the Carter/Edelbrock was the only carb I could get to work good offroad. Not perfect by any means but still much better than most other carbs. it does require fiddling with it (Not just the mods above but also the mixture) to get it working well though. I have no experience with the TA Holley's but you couldn't get me to run a stock one. (I would just as soon throw it in the trash) If I were to run a carb now though I think I would look at the Quadrajet turned backwards. (I already know forwards doesn't work too well)

06/17/06, 08:32 AM
I am having the same problem as of last night with my Holley TA , it dies when I put it it into Drive . It is strange because the idle sounds funny also now . It will idle smooth then drop a few RPMs and run smooth again every few seconds . It will die in park if rev the motor up a few times also . Its strange though cause the problem comes and goes ???
I will play with some more later today .

06/17/06, 09:59 AM
Before I went EFI, I had the same set-up as you. It took me awhile to get my edelbrock carb to run well offroad, but after installing and offroad needle and seat, fuel pressure regulator and a 1/2" phenolic spacer it worked great.

The regulator was the most important thing. The fuel pressure is overcoming the needle and seat when you hit bumps and flooding the carb with fuel. They'll all do that. I bought a cheap Purolator regulator with a dial. I would keep it set around 4 for in town and dial it down to 1.5 to 2 for offroad. Adjusting the float as described above also helps with this, but the ultimate cure is the regulator.

After I cured the stalling when I hit bumps it would quit at high altitude on hot days like it was vapor locked. After trying an electric fuel pump with no success, a friend suggested that I try a phenolic spacer. The aluminum intake was real efficient at transferring heat and the fuel was boiling out of the carb. This occurs at a lower temp at high altitude. I bought a 1/2" phenolic spacer from Summit and it completely cured that issue.

Another piece of the puzzle is your idle mixture. I found that it had to be right or the carb would hesitate or stumble at times. That's real easy to adjust on the Edelbrock. Just turn both idle mixture screws in all the way (gently) and then back them both out exactly 2 1/2 turns. From there hook up a tach and a vacuum guage. Adjust them in or out equally a 1/4 turn at a time until you reach the max vacuum and idle speed. At that point you can leave them which has you slightly rich, it will run well but not pass an emmissions test. I would turn them in 1/2 turn, when ever I had the annual emmision test and adjust them back out afterwards.

Lastly, depending on what altitude you are at you might need different jetting. At my altitude I went to smaller jets.

All carbs will suffer from these issues, but not all are as easy to adjust as the Edelbrock. Here's a link that may help .

06/19/06, 03:26 PM
Lastly, depending on what altitude you are at you might need different jetting. At my altitude I went to smaller jets.

What size jets did you end up with? We probably run about the same altitude; my driveway is at 6000, goes up from there.

06/19/06, 06:12 PM
What size jets did you end up with? We probably run about the same altitude; my driveway is at 6000, goes up from there.

Yep, same altitude. When I converted to EFI, I sold the manifold and carb to another Bronco owner and I really can't remember what jets I used. I used one of the charts in that link I posted as a guide.