Wobble

The proform main body and billet throttle plates are not USCG approved

hpy540

6.5 PV on front and back 89 front jets and 95 back

carb number 80330

i was spinning 5600 with no fuel and it was still pulling but slowly (94 mph gps w 2mph downstream current) i am running a 1.36 drive and a 27 pitch mirage that has been shaved quite a bit but never dialed to the boat i have to rering this spring and i am making a few changes. I was running 5400 with 7 people in the boat only doing 80 and it was topped out. it had no more. This is the time i melted the three pistons..... I had a distributor go bad. I have since replaced the dist. I know the proform body is not USCG approved. the main difference is the vent tubes and the pilots and a small plastic/uhm piece around the choke rod on the top of the carb. And sealed throttle shafts to prevent fumes from escaping in the bilge area. So for the sake of argument i am not running a hatch cover......

I am thinking about at least cutting the choke horn off.....

Roller hyd cam and 629 lift with 236 and 244 dur i cant remeber the Lsa right now.

Monkey Spanker

I would put the body on the carb, it's cheap enough, and is a hell of alot easier than cutting the old one. You should definately square jet that carb with the power valve in the rear. I would go to 92 square and start going fatter 2 jet sizes at a time. We ended up with 93 square with power valves on our drag cars. They were 650 hp 468's on 93 octane. Don't waste your money on a Dominator. We put one on those motors and gained nothing on the track, and they spun 7500 rpm.

hpy540

Ok so what about the differnce in throttle plates? And can a person use the 950 proform body with the rest of my carb parts?

Monkey Spanker

I checked out proforms website, and heres what I see. The 67108C main body is the same one used for 850 and 950 carbs. The throttle plate assembly is what makes the 950. The fact that is has the thinned shafts and button head screws make the 850 body flow 950. You will only have to use the 67108C body on your baseplate. I usually take the baseplate apart and thin the old shafts myself with a die grinder and put them back in with locktight on the threads. But once again, the thinned shaft kit is so cheap and simple to install, why not spend another 100 and have a real nice trick looking carb that flows great cfm? Heck a nice looking boat like that DESERVES a great looking carb.

Wobble

Be sure and tiewrap or glue on all the vacuum port boots and it is also a good idea to locktite any screws that can drop into the intake.

The last post in this thread shows the proform base plate http://www.offshoreonly.com/forums/s...75#post1315475