lance0730
New member
montynormand
Member
dependent on the year there either kehin diaphram or mukuni diaphram
GP292Racer
New member
Looks like a '73, so it should run twin 42mm Kehins if I'm not mistaken.
lance0730
New member
GP292Racer said:Looks like a '73, so it should run twin 42mm Kehins if I'm not mistaken.
I appreciate that...anyone else agree?
lance0730
New member
GP292Racer said:Looks like a '73, so it should run twin 42mm Kehins if I'm not mistaken.
can you substitute with mukuni?
GP292Racer
New member
You sure could, but you would just have to figure out jetting, which takes a bit more time, rather than having an adjustable jet on a kehin or tillotson carb
montynormand
Member
in my opinion, If your gonna just ride it for fun - ditch the butterfly's and do a mikuni. next question is wether or not to run a single carb, or run duals like its set up for. if it just gonna be a pleasure sled, I'd just go with a single mikuni
Snojet Steve
New member
I had a 1975 GP 433-G with a Tillotson from a Ski-doo TNT on it and it ran like hell. I recently found a better GP 433 G now that has it's original carb on it. I don't think I would use that thing if my life depended on it. Some of those reed valve engines will have blocks that allow dual carbs to be mounted. The 1974 Yamaha GP's, Sno-jet SST's and 75' SST's all have those. The 75' and up Yamahas, 76+ Sno-jets all have solid 2 into 1 manifolds so you have to find the older reed manifolds or do some fancy machining to run 2 carbs on them. That looks to me like it is a 1974 or 1975 carry-over GP 433-F. The gas tanks on the older ones are behind the seats and they have bogey suspensions.
lance0730
New member
Snojet Steve said:I had a 1975 GP 433-G with a Tillotson from a Ski-doo TNT on it and it ran like hell. I recently found a better GP 433 G now that has it's original carb on it. I don't think I would use that thing if my life depended on it. Some of those reed valve engines will have blocks that allow dual carbs to be mounted. The 1974 Yamaha GP's, Sno-jet SST's and 75' SST's all have those. The 75' and up Yamahas, 76+ Sno-jets all have solid 2 into 1 manifolds so you have to find the older reed manifolds or do some fancy machining to run 2 carbs on them. That looks to me like it is a 1974 or 1975 carry-over GP 433-F. The gas tanks on the older ones are behind the seats and they have bogey suspensions.
Very good educated guess... it is a GP 433-F (1974) it does have the 2 into 1 manifold..what is the best functioning single carb i could put on it?
GP292Racer
New member
36-38mm Mikuni would likely suffice, or a Tillotson HD. Some time would have to be spent for jetting with the mikuni, but if you can get an HD with variable mixture screws, you can adjust on the fly and be on your way a little quicker.
lance0730
New member
Snojet Steve
New member
That sled should look nice when it's done! I like the tunnel mod! The HD 138 I had on my old GP-433-G was from a 1974-75 Ski-doo TNT 440. It had about a 5 mm bigger bore than the stock keihin so I had to grind the intake manifold a little bigger to match. It ran extremely well and the stock GP airbox matched up to the Tillotson carb.
GP292Racer
New member
I find tillotson carbs WAY easier to deal with than the stock kehins. I've been racing my 292 for 2 seasons and still have a slight bog with that kehin
lance0730
New member
thanks for the Input guys.