FUELforTHOUGHT
by Dave Koehler
9/8/06
 |
|
|
|
 |
Steve,
I am not a carb guy but try this. Make a couple of baseline runs then richen the jetting. If it goes quicker, then richen it up again until it slows or quits improving. Then lean it down a couple of thousandths. If richer jetting slows it down immediately then go the other way and lean the carb down.
You are probably wondering about this going richer deal. Since you didn't mention severe dilution of the oil with alky due to over richness there is the possibility that you may be waaay too lean. It is possible to be so far past the numerically correct A/F ratio point that there is not enough fuel in there to make any power. It will still run but not very well. A byproduct of over center leanness is no heat. Weird but true. Granted, I would like to see more heat in it at staging but go for ET and let the temperature fall where it may.
While on this subject I want to add that I have never seen a modified carb for alky that works as well as we hope. Fuel injection is the better route for running alky. Nudge, Nudge. One major flaw about carbs and in particular alky carbs is that they need more float bowl volume to feed modern racing engines. I recommend the McClintic dual needle and seat bowls. These work real well and solve 2 or 3 issues. Why do you need these? Think of it this way. You have 2 jets of .185 diameter in each bowl but only one needle and seat of near the same diameter trying to feed those two jets. Do you see the cork? High fuel pressure won't solve the problem either as it is not fuel injection. Let us know how things work out.
McClintic RDM Inc. 505-292-1311
Have a safe race,
Dave Koehler
www.koehlerinjection.com
|
|
 |
 |
|
|
|
|