Plug reading........

[slocrow]

I used to be able to read a plug and know which way to go when attempting to alter the Air/Fuel ratio. When discussing that procedure recently, at a local cruise night, I was informed that with today's fuels it's extremely hard to do.
I ask because I've recently been attempting to lean out my carb and this leaning action has apparently made no change in my plug color. Still black like it's too rich.
The locals stated that it's the fuel additives that leave the plugs and tailpipes black making this procedure for A/F checking almost obsolete.
I know Ohio gets the worst gas because of no or very limited state regulation and I was just wondering if it's still possible to use this time tested method, or has it been compromised nationwide....Thanks, Frank

[Charlie Chops 1940]

I use the smell test...can't smell gas...it's OK. Well, maybe not a real reliable method but without some test equipment to analyse the mixture it's kinda tough. I agree with your advisors that the current unleaded fuels don't leave the same plug colors that us old guys are used to.

My suggestion is to get rid of that 750 and drop back to a 600 and go from there.

Charlie

[enjenjo]

I agree with Charlie, go with the 600. there will bo no real difference in power under 3500 rpm, and the air flow will be better, eliminating some of the mixture problems you are having.

You can get one of the air/fuel ratio meters that uses a 02 sensor to monitor the mixture. I believe Sumner has one on his truck.

Of course EFI takes care of all of this

[slocrow]

Thanks Guys, I always appreciate your 4 cents. I agree and believe it's a 600 for me. After all the 750 is just a hot rodded 600 anyway and with 400 cubes the formula says I only need a 590 @85%.........Frank

[Charlie Chops 1940]

Frank and I believe you have made a good choice grasshopper (LOL). Is Summit open today?

Charlie