Belt Life Screw Blower, Help!!!!

I am having zero to low luck with belt life on my new screw combo. My 14mm belt are coming apart anytime I hit a rev limiter (two step or if I spin). Would like to run 125 over if I could get a belt to stay on. I adjust the belt super tight as directed.

What mm lives and what part number? I have both snouts for 14mm and the 11/8mm. I am just flabbergasted at what poor belt performance I am getting. Done sorting for the season and will pull motor for new rods and freshen.

Help!!!

 

overdrive now?

what overdrive are you running now and what belt? I have run 16 passes with no problems yet, but may not be running as hard yet? We are running 4.01 to 4.05. now at 2560 lbs with driver @ 8800rpm shifting and at the stripe Thanks

 

I was trying to run 125 over, it threw belts all the time. I was advised to reduce the overdrive to 86 over to be easier on the belt.

 

check your pms

 

We run @ 128 over with an 11mm belt and the belts last forever. Is there an alignment issue. With the previous motor we ran 116 over with the 14mm stuff no problems.

 

Thanks for the multiple replies

Going to pull the motor, change rods, and spend a bunch of time verifying everything is aligned perfect. Thinking the 11mm 84mm belts. What pulley combo did you come up with 128 over? My heads are more conducive to lower RPM.

I appreciate all the help and advice.

Scott

 

57 and 25 pulleys 1705-84 belt on a 481x. You need to measure crank to blower centerline. What engine and intake manifold/spacers.I have lifted the blower and reused the belt.I think this is one of the toughest belts out there.

 

Thanks for all the advice and help. Will be going 11mm 84 wide, PS belts.

Appreciate the help!!!!
Thanks to ITA as well!!

 

Belts

Most of the top alcohol cars run the 8mm belt. Probably better than 90% of them. So when you are at the track and need to beg/borrow/buy belts or pulleys it would be easier to find 8mm parts. I know of guys who had repeated and frequent belt failures on belts that were properly tensioned and running true and that changing things like fuel pumps fixed the belt problems. Belt failure can be a sign of other issues with the motor. Just like how detonation sometimes shows itself by loosening bolts. Dave Germain