I'm looking for advice to improve the off the line acceleration for my sled.
I have a 1990 Indy 650 that always used to have more power than I needed. Normally it was limited by traction. I recently installed a Aggressor 1" track...
This track sticks like glue and even with the suspension set up to not lift the front end and me leaning forward, on the right snow it will lift and keep lifting (around 30-40 mph). The machine absolutely flies (acceleration wise). Top speed is down a few mph though (but I love the traction, so I'm happy).
The problem is now the machine is missing a little from about 0-10 mph (not much - but it could be faster). I tweaked the clutching to bring the engagement RPM from 4200 up to 4600, and it's better, but it's not enough (I weigh about 210 & some of my friends still pull away off the line a little). The max RPM is still set at 8200.
I figure I could either bump the engagement further to 5000 , but I really like the drivability the way it is. I'm contemplating changing the gearing from 21:35 to 19 or 20:35. I'm worried about not having enough clutch gearing to keep my 100 mph top end (without revving over 8200).
Does anyone know how much more room (gear wise) there is on the clutching? I figure the primary and secondary clutches are pretty much maxed out at 100 mph at 8200 rpm, but all I need is 6% gear remaining to run 19:35 sprockets. If there's no room then I guess increasing the engagement rpm (or tweaking the motor) is my only option. I'm going to try tightening the belt a little beyond spec, but I don't know how much that will improve things.
I'd appreciate any advice/info.