plug gaps

essexcoupe3131

All you guys with small blocks, what would you set the plugs to on a Edelbrock

small block with MSD and 6AL non vacum distributor



Thanks Mike

Lee ODell

Hi Mike, I'm assuming this is a driver not a race car.



I would stay close to Chevy's recommended .035 gap. The greater the gap the spark will go to least resistance. The more gap you use, the harder it is on the MSD, ignition wires and distributer cap. When the MSD goes bad you will think the engine is coming apart. (My personal experience).



You didn't mention which Edelbrock engine you have. If you have the Edelbrock supercharged engine go with slightly smaller gap. Don't get carried away changing gaps in either direction.



Why not use the vacuum advance. It doesn't harm performance and it will improve normal driveability. Also, gas mileage will be much better. I even used vacuum advance on my supercharged 350 El Camino and was getting 24 MPG on the highway. Only without the lead foot.



With the old stock 327 engine I was gettling 26 MPG and turning 90 MPH in the 1/4 mile drag races using the vacuum advance.



Going to far astray from factory specs generally reduces performance and and much time and energy is wasted trying to find out why you didn't get the hoped for improvements.



I like performance but not at the expence of reasonable good gas mileage.

I prefer 20 plus MPG for my driver.



Just my two cents. Lee

essexcoupe3131

Thanks Lee for your imput, its a 435hp and torque, all the literature I have been reading says at least 45,000, I can,t run a vacum unit as the cap clashes with the fire wall, this is why i put on the 6AL to try and sort it out, the Edelrock site says we should run short plugs in a heat range of 4 (NGK) but have ended running colder 6 range (NGK) longe reach as it was the fowling plugs too much

I know that the bigger the gap you go you can start losing power it over 6k range

I was looking to see if any had ideas or sugestions as you boys must have played around in this area



thanks Mike

Unknown

Mike, are you running a carb, or injection system? I run twin Holley's, and had to jet the carb's waaaay down to get the proper mixture. When I was dirt-tracking, we'd make a few hot-laps first. At the end of hot-lapping, I'd let off the gas, put into neutral, and kill the engine, as one move. I'd then coast into the pits, pull the plugs, and see how the plugs were burning. White ash is too lean, grey to light brown is perfect, and obviously black was too rich.

hudsontech

wkitchens wrote:

Mike, are you running a carb, or injection system? I run twin Holley's, and had to jet the carb's waaaay down to get the proper mixture. When I was dirt-tracking, we'd make a few hot-laps first. At the end of hot-lapping, I'd let off the gas, put into neutral, and kill the engine, as one move. I'd then coast into the pits, pull the plugs, and see how the plugs were burning. White ash is too lean, grey to light brown is perfect, and obviously black was too rich.

From experience - melted electrode is way to hot.



Hudsonly,

Alex Burr

Memphis, TN

Lee ODell

Mike, what kind of car is the engine in? Is it in an Essex? Are you using a point distributor or HEI? What carburetor or fuel injection unit?



I had a small block in my 35 Chevy coupe, about the same size as the Essex, with the distributor almost touching the firewall. For the vacuum advance to clear the firewall I rotated the distributor counter clockwise and moved all the plug wires clockwise one hole. Clearance problem solved.



Will you post some pictures. Would like to see your car.



Have a good day, Lee.

essexcoupe3131

thanks all, its the Edelbrock crate engine and has a av preformer carb on it that runs out too 800 cmf got , its in my Essex coupe,

thanks Mike