Custom Supercharger Belt Lengths?

Hi, we have a tall deck 434 sbc with an F-1R Procharger,and we have been fighting belt length problems. We can't find the right length for it. We run a 73 tooth crank pulley and a 38 tooth blower pulley,we run 8mm stuff. We tried a 1512(189tooth) 8mm belt and it was too short so we bought a 1600(200 tooth) 8mm belt and it is too long,so we found a 1584(198 tooth) 8mm belt,and it was still too long,so we put a 40 tooth blower pulley on it,and it worked a little better,but the belt is still too close together(it almost touches together with a little tension on it). We can't change sizes of the crank pulley,because of clearance around the rack steering. Don't want to go bigger on the blower,because it will slow my blower down,can't go smaller on the blower,it would spin it to much. We would like to switch to a gear drive,but don't have the funds right now.

Does anybody know were I can get custom length blower belts such as Dayco,Bando,Gates or somebody? I think we need somewhere around a 1540 length,so we can put our 38 tooth blower pulley back on. We run the 8mm GT profile pulleys.

Can someone help us out? Thank You,Brian

 

Are you running the belt on the inside of the idler? Have you tried running it on the outside or changing idler pulley size? Another idea would be to check one of those blower ratio charts to see what combination of smaller pulleys would give you close to the same OD. An even better idea would be to call JR at RBS. He is a pro at sorting stuff like this out. I am betting you aren't the first guy to have this problem. Dave Germain

 

It's not what you want to hear but can you move the blower by changing the brackets?

then you might be a ble to get a belt short notice if you need to replace it at the track.

 

Rack clearance

 

years ago we ran a sb chevy and it was like yours I used to get the belts from jim mayor from good vibration motor sports a little pricie but jim can help you out...if you need the belt # I still have an old belt here that I can get the #'s off of..Dave