Jerry said "a decent sized slide carb", I have been looking at Tillotson/Mikuni carburetors but I have no idea what size i would need. Any suggestions?
Top speed is not that important. We don't have a lot of space to ride. We want it to be quick with a lot of torque. (it's no fun going around corners unless you are sideways )
The carb I was thinking of trying to hunt down would be a 22mm Mikuni or equivalent. That would keep the intake velocity up within your projected RPM range which brings me to part 2 of the quote box....
Box stock, these motors are torquey wheel-spinners, and with a torque converter you'd be tearing things up pretty well. Rather than "building" the motor, I'd invest in a good drive system (torque converter) that will take advantage of what you already have. A 22mm carb is very close to the same size as the stock one, but the big advantage is the better fueling, and it's less upset by bumps, turns, etc. I would think that as long as the motor is in good tune, clean oil, fins/blower cage kept clean, that it should serve you well up to 4500 rpm-ish without a problem. With proper gearing, you won't be able to top that, and you'll still have great acceleration (THX to the torque converter).
As an aside, in a late 70's/ early 80's car magazine, some guy, who was after ultimate gas mileage, took a stock B/S 8hp, a torque-converter, and put it into a VERY aerodynamic 2- seat body that looked like a Lear-Jet with the wings removed, (About 12' long in length)... this guy was getting top speeds just above 70mph, with the STOCK B/S! Of course the mag downed the guy for using the B/S instead of a more efficient motorcycle engine, but in retrospect, at the time, most "utility/project" engines that were self-contained and had their own cooling were pretty much flatheads. (I don't think the Honda OHV's were around 'til quite a bit later.) The point (is there EVER a point to my drivel?) is that the stock B/S 8hp is a pretty kart-able package, with the right mods to the drive/vehicle.
Readers of my threads will ask, "Hey Jerry, if the stock B/S 8hp is soooooo great, why is yours collecting dust on the back porch?" Two reasons.... NONE of my present karts will handle it's size/power safely, and I would've built a lowrider specifically for it, but the snowmobile motor landed in my lap at a crucial time. I chose to invest my VERY limited funds in the better motor. The 8hp will have it's day, though.
We grab it, took the motor out, and decided we need a go kart. the motor is a B&S 195432 8hp. Our motor will not start. We decided to rebuild it and the carb. While its apart we thought we would remove the gov, replace the flywheel, rod and springs. I can find a lot of parts on line for 5 and 6 hp but not he 8hp. any ideas how or where to find the correct parts or a high performance kit
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