On stock 74 GPX338, will spring or cam have more effect of changing engagement of clutch. I'm running Spring #90501-55419 with stock cam. This set-up is engaging at 4000-4100, shifting out at 8200-8300. I would like to get it up to 4800-5000. Sled rips in mid and high range but is a dog at takeoff. On stand it is the same way. Could this be a carb issue? Again, engine is all stock, with stock carbs and air box. The secondary is stock. I would like to do a little drag racing with it. I have gone down one tooth on upper gear also. If anyone has a secret set up I'd love to know what it is, I can't seem to find it's sweet spot.