Folks,>

All right. I have been having a slightly rich problem with my 2016cc. My> exhaust pipe is getting quite blackened by carbon. I don't exactly smell> gas, but suspect that I am running rich by the residue on my pipes and plugs> (Bosch W8 ac). I am running a 78mm crank/90.5 P/C's, and FK7 cam with Scat> 1.4:1 Ratio rockers. Ported and polished heads matched at the carbs, but not> to the head. On the carbs, I am using F11 emulsion, 200 ac, and 135 main,> with velocity stacks on Berg 580 polished intakes. The heads are ported and> polished, and I think are 42 exhaust, 36 Intake. I'm running a merged 1> 5/8's exhaust with a stinger and spark arrester.>

The problem is that the carbs don't respond when trying to adjust the> mixture screws. I used the settings from the Weber manual and the engine> fired up immediately. Just idled a little fast. I've run the engine like> this for a few seasons. (Strickly summer and fall) The engine never> overheats, doesn't leak oil. Has never set off the Berg oil dipstick. I just> can't help but think that I am robbing HP with this rich condition. The> engine pulls hard and spins up like a motorcycle, but the front end of my> dunebuggy would only lift in 2nd gear, and only maybe 1/2 inch off the> ground, and it's a very light vehicle. The wheels would only break loose in> rain. (Although I was running 295 65 R15's.) I've measure the deck height> and cc'd the heads twice. I can't find the numbers just now, but remember> the CR being at 6.9:1 each time I measured. I spoke with Jake Raby, and he> correctly surmised that:>

A) I read a lot of Gene Berg articles> B) My compression ratio is too low> C) The engine would get much snappier if I switched from 92 Octane to 89> Octane.>

He got A and C correct. Is it possible that my compression ratio is too low> and affecting the performance of the engine and carb mixture?> I am also running electronic ignition. Pertronix I think.> I have tried a Jacobs coil and a Bosch blue coil with the same result.> Is there something I am missing here?>

Your thoughts would be greatly appreciated. I would like to get a handle on> this before I start the new season.>

Thanks,> Matt from NH