Heat soak issues.
Thread Starter
2nd Gear
Joined: Mar 2022
Posts: 2
Likes: 0
From: Texas
Heat soak issues.
I am looking to convert to a Holley Sniper throttle body EFI system. Heat soak is killing me on my L 82 with Edlebrock intake and carb. Any thoughts on this? 1977 L82 Original 350.
Thread Starter
2nd Gear
Joined: Mar 2022
Posts: 2
Likes: 0
From: Texas
Flooding
When car warms up, carb seems to percolate fuel. I have read that it because ethanol boils at 180°. I have not tried a heat shield. If I do, how thick can I go with spacer?
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,034
Likes: 4,177
From: US-PNW
Does your Edelbrock intake have the exhaust cross-over passage? If so, you may want to research using intake gaskets with blocking plates to eliminate the exhaust gases from heating the intake.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,026
From: New Braunfels Texas
What carb base gasket are you running? It should be 1/4" thick.
What is your timing set at? Excessively retarded or advanced timing can raise EGT's and underhood temps dramatically.
10% Ethanol fuel can boil at 200-240 degrees F.....it really depends.....I have never seen pump fuel...but it is probably not impossible.
There are thousands of Q-Jet equipped Vette's that run just fine with the stock system on today's fuel and yours can too.
Jebby
What is your timing set at? Excessively retarded or advanced timing can raise EGT's and underhood temps dramatically.
10% Ethanol fuel can boil at 200-240 degrees F.....it really depends.....I have never seen pump fuel...but it is probably not impossible.
There are thousands of Q-Jet equipped Vette's that run just fine with the stock system on today's fuel and yours can too.
Jebby
Le Mans Master
Joined: Dec 2003
Posts: 5,381
Likes: 415
From: N J
I had the same problem on my 77.
Edelbrock rpm performer intake and 750 Edelbrock carb. I could not restart the car when hot without holding the pedal to the floor and cranking.
I could hear the fuel boiling in the carb after shut down.
4 longer studs and a 1/4" spacer did the trick. Much better now.
Edelbrock rpm performer intake and 750 Edelbrock carb. I could not restart the car when hot without holding the pedal to the floor and cranking.
I could hear the fuel boiling in the carb after shut down.
4 longer studs and a 1/4" spacer did the trick. Much better now.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,026
From: New Braunfels Texas
I will add that if you use a 1204 Fel-Pro gasket that blocks the heat riser it will lower the carb pad temp about 100 degrees.....then you just convert the choke to electric which is super easy to do on a 77' and cheap.
Jebby
Jebby
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Le Mans Master
Joined: Apr 2011
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From: Hermosa
My 77 did the same thing in it's stock config. What really helped was blocking that crossover heat, but until I did that I did put on a thick insulating gasket between the carb and intake and that helped a lot.
PS you don't need a choke unless you plan on running in the winter, get rid of it. I've been running chokeless for over 10 years.
PS you don't need a choke unless you plan on running in the winter, get rid of it. I've been running chokeless for over 10 years.
Is my vette stock?? HAHA
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I have an L88 hood which gave me a ton of room for thicker Phenolic spacers, I like 1 inch. I new hood and paint might be less than the $4000 for the EFi when its all said and done. You need the EFI, Fuel pump, 2 filters, return lines, most likely a single plane intake, and if you want to use the timing control the either an MSD setup or the Sniper plug and play distributor....