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-   -   L78 idling issues (https://www.yenko.net/forum/showthread.php?t=105757)

Jeff H 07-11-2009 10:12 PM

Re: L78 idling issues
 
My 70 L78 Camaro never had that problem but the motor wasn't stock spec L78 either. It had the stock 569 intake and a generic Holley 750 with no choke setup and double gaskets, no heat shield. Maybe try the double gaskets or heat shield to reduce the temp at the carb itself.

WILMASBOYL78 07-12-2009 12:50 AM

Re: L78 idling issues
 
I think it's the bad air on Long Island https://www.yenko.net/ubbthreads/imag...s/rolleyes.gif https://www.yenko.net/ubbthreads/imag...s/rolleyes.gif

Salvatore 07-12-2009 01:22 AM

Re: L78 idling issues
 
Maybe a vacuum leak. When cold it runs a little richer. When hot it vaporizes. I would go over and retrace all your steps and make sure the set-up is the same as it was before you took the intake and distributor out. Recheck idle circuits, dwell,timing and any lean condition around the carb and intake you may think you have. It didn't do it before so trace your steps. https://www.yenko.net/ubbthreads/imag...lins/dunno.gif

ss427copo 07-12-2009 01:49 AM

Re: L78 idling issues
 
I had taken the heat shield off a few years ago and ran around for a few weeks and began to have "silly" carb issues. SO.....I put it back on and they went away https://www.yenko.net/ubbthreads/imag...s/confused.gif Haven't had any since. AND....the plate has been there since 1972 when BWAG owned the car as a SS/EA. He even painted the underside of it gloss white. Ugly? maybe...Works? Way to go Bob! YUP! (smart man!)
https://www.yenko.net/ubbthreads/imag...ns/naughty.gif
http://i141.photobucket.com/albums/r...c/100_4028.jpg

http://i141.photobucket.com/albums/r...c/100_4027.jpg
Jeff x 3 https://www.yenko.net/ubbthreads/imag...ns/burnout.gif

JRSully 07-12-2009 04:24 AM

Re: L78 idling issues
 
an update, I forgot to mention that I am running original Motion alum v/c's which are taller and fatter than stock. This brings the stock air cleaner to almost touching and now "shrouds" a lot of heat (lack of air flow) around the fuel lines near the carb bowls and with the new intake gasket now allowing the heat crossover to function, just exacerbated the problem . Tried an experiment, pulled the air cleaner and wrapped some alum screeing around the air horn. Drove the car for about 45 min's, about 80 degrees through all conditions (stop and go,h'way etc.) and the problem almost entirely went away. I think the fuel is getting boiled by the air cleaner base and valve covers, too much heat in the vicinity. Going to install an air cleaner spacer on top of the Holley and put the heat shield on and hopefully that should do it. Wilma, for once, the weather was picture perfcet here on LI today. Thx for tips SULLY

Salvatore 07-12-2009 04:35 PM

Re: L78 idling issues
 
Also make sure the top of the air cleaner is not touching or to close to your bowl vent tube when the lid is tightened up. Sometimes the air filter is not tall enough placing the top of the air cleaner lid too close to the vent tube.

JRSully 07-18-2009 05:12 PM

Re: L78 idling issues
 
Put the heat shield on and 1" air cleaner spacer, about 80 degrees out now. I'm going to hit my favorite 1/4 mile stretch on the other side of town shortly and see if the problem is cured once and for all, stay tuned

Salvatore 07-18-2009 05:23 PM

Re: L78 idling issues
 
Let us know......... with a VIDEO!!! https://www.yenko.net/ubbthreads/imag...ns/worship.gif https://www.yenko.net/ubbthreads/imag...iggthumpup.gif https://www.yenko.net/ubbthreads/imag...ins/3gears.gif


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