Super Jet What carb to go with

[fast superjet chase]

What is the best carb or carbs to go with on a 760 sj for freestyle?

 

[score602]

what is done to the motor?

 

[fast superjet chase]

Ada head with 180psi factory pipe msd enhancer freestyle port job vforce reeds riva reed spacer currently running a single 44mm carb hooker 9/15 prop my problem is that im trying to get low end out of it and it just doesn't seem to be there

 

[score602]

Dual 44's will def be an upgrade, gotta tune that pipe good too

 

[motoman96]

This is a loaded question....

 

[eak_photography]

if you wanna save money get a dual carb intake and another 44, i run dual novi 48s on my 760 and its got the rpms up and down

 

[fast superjet chase]

my only problem is that im at 5000ft and i tried to run a single 48mm power bomb carb and didn't notice any difference between that and a 44mm stock carb and my pipe is tuned in so i just can't under stand why i'm not have the low end power. does any one think that the stock 38mm carbs off a sj is worth running?

 

[Crab]

stock 760 cyl?? Who did the porting.

 

[ajmps1]

61x case assuming? single 46sbn will not displease, or send the stock 44 to art at jetworks and brapjacks for breakkkkie

 

[fast superjet chase]

i ported them with templates, and it is 62t cases. all ports are matched and have been put onto a flow bench. it was not my first port job i have done numerous cylinders and this is the only motor i have had trouble getting low end power.

 

[fast superjet chase]

so my timing plate is advanced while i'm running a msd enhancer. Im thinking that may be my problem. what do you guys think?

 

[JetManiac]

Advanced timing is good for low end power, not your problem.

Is it a 62t or 61x cylinder? Higher port timing in the 62t cylinder makes it harder to make low end power.

Dual oem 38s are cheap and make good power. Some like the oem 44s also.

 

[aramis]

just give some stock dual 38's a try. Everybody knocks them, but they work and they work well. Based on a simple area calculation, they can flow 1.5 times what a single 44 can...bomb sight / boss areas not subtracted. Dual smaller carbs should theoretically respond more quickly than one single carb also.

For the record, I've now tried 2 sets of modded 38's (w/ a filled crossover), back to back on two different skis and on both skis the stock 38s (w/o filled crossover) have a faster response. Both skis are ported, one a 701 and one a 735. In both cases the modded 38's were smooth, no tuning issues or anything...but lacked punch. I'm working on a video comparison.

I've also tried with and without an angled reed spacer, and I ended up taking out the reed spacer. Seems as if the extra crankcase volume created by moving the reeds back causes a delay / dampening of the pulse signal (and the pull on the reeds).

B-pipe can contribute too...if you're running with the top screw open, I'd try closing that and giving it a try with just the bottom screw open 3/4. (You can probably close it more than that but that's safe to try.) I went back and forth on this but once the other tuning was right (carbs / prop / etc), the bottom screw gave me the most bottom to mid punch.

 

[fast superjet chase]

The cylinders are the 64x cylinders