Please help. Have a SBC with two fours, small heads, .500 Comp cam, 4speed ,Headers , 3:42 rear gears and a stock GM hei. With that said this "beast" seems to eat plugs every 400 miles. Have AC 44s in the motor now. What plugs do you folks recommend to solve this problem? Also have a problem changing plugs with these headers and thought that the new "shortie" plugs may help ( lots of pain in my old fingers)but have never used them. Thanks for your time and may God bless u all.
What do you mean by eating plugs? Are they fouling out? If so, what do they look like? Crusty carbon or wet and oily? Are they all like this, or just the rear ones?
Motor has maybe 1500 miles on it. Run very rick as i have taken the chokes out.Just a summer car. Starts missing after 400 miles ans all the plugs look dark and sooty.
What kinda carbs? Holleys? Make sure the float level is right. Ever backfire out the carbs? If yes on the Holleys ya may have killed the power vlaves.
Sounds like you need to tune the carbs to me. If it's fouling out and it's running that rich. Tune them a little leaner....
Yeah sounds like a carb issue, not a plug issue. You are geting spark but it sounds like you are just getting too much fuel into the combustion chamber.
I see you have a HEI ,is there 12 volts to the coil?I have also this problem on a chevy with a bad or weak coil.
Thanks fellows. The carbs are new Edelbrock 500cfms and all the parts were new when the motor was built including the HEI.The retune the cards may be the answer.
Fix the carbs,check for full voltage at coil-not resistor voltage,hope like hell the cylinders are not gas washed from all that gas going by the rings,change the oil-it's got to be contaminated with gas>>>>.
First change the OIL--the rings are gas washed like some of they guys have said. Call Edelbrock and talk to there tec guys. They should be able to give you a jet and rod size to go too. Also i'd look at an aftermarket coil accel makes one that bolts right into the top of the cap and looks stock. Also use an advanced timing light to check the timing and make sure the advance is working.
1000cfm of edelbrocks presumably straight out of the box on a tunnel ram on a small block chebby would need to stay pretty wound up to not foul plugs. When you add in the small heads and "only" a .500 cam you'll need some serious carb tuning to get it not to foul plugs. I dont mean to sound rash, to a fellow Kentuckian especially, but its a lot of carburation for that combo.
Is the linkage progressive or 1:1? If the carbs came with the Edelbrock manifold, as a kit, the carbs should have the correct rods. The kit also supplies other rods for bbc applications.
I would have to agree with most here.. way too much fuel for that engine. I would say 1000 CFM is a bit much on an SBC that isnt highly modified to handle and breathe that much, with the small heads, the larger cam..its just too much fuel getting litterally dumped into that engine. you would probably benifit from a single carb intake and one of those Carbs., that engine might wake up and run better too. Or a progressive linkage, with very little of that second carb comming on at 3/4 to full throttle. Although like others have said , you may have already fuel washed those rings to the point of creating other problems maybe with only 1500 miles on it you may be ok.. JM2C
Sounds like you only masked the real problem. If the car was running rich and fouling plugs why not tune the damn thing?
Thanks fellows. Engine was built by a Very good circle track engine builder with 40 years under his belt.I very rarely kick in the second carb and with a slamed 57 chevy I like it "Low and Slow".LOL Maybe I need to "Ring it out more offten"LOL.
Also, put a good curve kit and adjustable va***n advance in that HEI, and like several others have said, run a full 12 volts to it, the early 12 volt Chevies had a drop down resistor on the firewall, do away with that.
I'm from circle track country and have fought this problem my whole life. The best circle track engine builders don't build engines that idle, they build stuff to pull a front tire exiting turn 2 at 6500 rpm. Very smart, very capable guys. But their knowledge base is built upon their customer demands. And racers don't demand idle quality that keeps plugs clean without constant revving. dual quads + small heads + 500 lift cam is gonna cause you fits. What's happening is fuel is falling out of suspension in the intake manifold because of insufficient velocity on the fuel/air mix. When it starts to puddle on the intake floor you're hosed, expect the plugs to foul. If you don't want to change your mechanical combination, consider an MSD or Jacobs multi-spark to try and keep the electrodes clean. BTW, gearing can be a huge help or hinderance with your setup. 3.73 or higher numerically will put you in the rpm range where the plugs might self-clean with a few blocks of travel. good luck
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