Edelbrock Carb Issues
Thread Starter
Instructor
Joined: Feb 2011
Posts: 234
Likes: 15
Edelbrock Carb Issues
Hi All,
I have a 1975 350 4spd. I purchased and installed an Edelbrock 1406 600 cfm carb. When the car idles everything is fine including revving the engine. However when I put the car in gear and go down the street the engine sputters like it's going to stall. I need to take the car out of gear and pump the pedal to keep it going. Sometime this will not work and the car stalls. When it does stall out I pump the pedal once and start the car up.
I changed the rotor, distributor cap. coil, spark plugs, spark plug wires, fuel filter, set the timing to 6BTDC. Adjusted the electric choke flap when the engine was cold to a the thickness of 3 credit cards.
Today I installed a fuel pressure gauge and at idle the needle bounces from 4 to 8 sometimes 9. I checked down the barrels of the carb and don't see any fuel dripping down. The only fuel I see is when idle and I rev the car up.
I can't figure this out. Why is it stalling when in gear? Can anyone please help?
Thanks
I have a 1975 350 4spd. I purchased and installed an Edelbrock 1406 600 cfm carb. When the car idles everything is fine including revving the engine. However when I put the car in gear and go down the street the engine sputters like it's going to stall. I need to take the car out of gear and pump the pedal to keep it going. Sometime this will not work and the car stalls. When it does stall out I pump the pedal once and start the car up.
I changed the rotor, distributor cap. coil, spark plugs, spark plug wires, fuel filter, set the timing to 6BTDC. Adjusted the electric choke flap when the engine was cold to a the thickness of 3 credit cards.
Today I installed a fuel pressure gauge and at idle the needle bounces from 4 to 8 sometimes 9. I checked down the barrels of the carb and don't see any fuel dripping down. The only fuel I see is when idle and I rev the car up.
I can't figure this out. Why is it stalling when in gear? Can anyone please help?
Thanks
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,181
Likes: 9,315
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
what is your idle speed in gear and have you adjusted the 2 idle set screws with a vacuum gauge
Thread Starter
Instructor
Joined: Feb 2011
Posts: 234
Likes: 15
Racer
Joined: Oct 2009
Posts: 276
Likes: 68
As a baseline, the 2 idle mixture screws should be 1.75 turns out +/-. If the primary throttle blades are open too far (idling too high) this circuit doesn't matter as circuit is bypassed. I would try giving some more ignition timing as 6 btdc sounds a little low. I always set distributor at full advance and adjust from there. curve, advance , fuel, cam and compression always play a part. try a little more initial timing and see if it helps. easy enough to go back.
Those Weber/Carter (Edelbrock) carbs are very simple carburetors. Unless some dirt clogs the needle and seat, a very good , albeit ugly carburetor (compared to a Holley). I was required to run them for my class in my last race car and heavily modified them, which was actually very minimal baseline mods. Very good, simple carburetor.
Those Weber/Carter (Edelbrock) carbs are very simple carburetors. Unless some dirt clogs the needle and seat, a very good , albeit ugly carburetor (compared to a Holley). I was required to run them for my class in my last race car and heavily modified them, which was actually very minimal baseline mods. Very good, simple carburetor.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
I don't believe the carb is the problem, at least not all of it. Timing is way low @6*, try 12 to 15. Check that the vacuum advance is connected to manifold vacuum ( right vacation port on front of carb) and that the vacuum advance diagram is functioning.
then tune the carb.
then tune the carb.
Thread Starter
Instructor
Joined: Feb 2011
Posts: 234
Likes: 15
First tganks for your help. The 12 to 15 is that timing with the vacuum advanced disconnected from the distributor and plugged or still connected to the carb. Also if I'm standing in front of the carb is that vacuum connection to my right of left
Racer
Joined: Oct 2009
Posts: 276
Likes: 68
If you have an adjustable timing light set it at 38 degrees and raise rpm until timing stabilizes and all in, usually 2500rpm. Only way I've ever done it. too many variables involved. And yes, you can double check initial timing afterward. May surprise you.
My race cars have the timing locked out so you usually can set the timing within a degree or 2 before installing the engine in the car.
My race cars have the timing locked out so you usually can set the timing within a degree or 2 before installing the engine in the car.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Once you advance the timing you'll need to back down the idle RPM to a normal RPM, 700 to 800 out of gear 600 in gear or something close to those numbers.
Last edited by REELAV8R; Sep 5, 2018 at 12:47 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
