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Author Topic:   Jet Size for Alcohol
Dirt Newbie

Total posts: 2
posted May 11, 2002 02:07 PM
I am finally making the switch to Alcohol and need some help. I have a 750 C&S Carb on a 351W with World Product Heads. We run at tracks from 4,000 to 5,000 ft. elevations. Where is a good spot to start? Do the plugs look the same on Alcohol as Gas? I've had a ton of advice, most guys telling me to get rid of the Ford, but I don't believe alot of it since the guys giving it seem to be burning their engines up twice a year. Any help will be apreciated.

Dirt Freak

Total posts: 238
posted May 12, 2002 07:30 PM
There are so much more modifications inside a carb that need to be done when switching to alky and just jetting. If all you do is jump up to a giant jet, you will still burn
up the motor.
Metering blocks are specially machined internally, power valve circuits are modified,
and basically, the entire carb is different.
Not to mention the fuel pump system as well.

Your best thing to do is to send the carb to a knowledgeable rebuilder (or back to C&S) if you have a shoebox full of money, and have the carb modified to change over to alky.

Best of luck, and once you get it switched over correctly, I am sure you won't regret it.

Dayton Umholtz, owner
Kinetic Performance

Dirt Freak

Total posts: 238
posted May 12, 2002 07:35 PM
Ya know, after I re-read the post, I realized I may have misinterpreted it. Were you saying you already had a C&S alky 750 carb? If so, jetting # suggestions would be best coming directly from them, since they are the builders of the carb (and know what machining was done to it). The jetting will be one thing with a standard metering block that is modified for alky, and a totally different numbering system for a metering block that was designed to accept the much larger jets that are typical in aftermarket alky metering blocks.

At any rate, hope that helps...and sorry for the confusion.


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