Author Topic: 8mm pullies  (Read 281 times)

Offline hotrod316

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8mm pullies
« on: August 06, 2019, 12:17:23 PM »
looking for some 8 mm pullies  42 and a 60 something close to  25% under drive thanks

Offline Paul New

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Re: 8mm pullies
« Reply #1 on: August 06, 2019, 05:32:54 PM »
I do not have any for sale but a 42 top and a 60 bottom is 42% OD I may misunderstand your question though

Offline hotrod316

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Re: 8mm pullies
« Reply #2 on: August 07, 2019, 06:05:09 AM »
UNDERDRIVE  -25%  BIG ONE ON TOP,  LITTLE ONE ON THE BOTTON I THINK
ONLY WANT 2 MORE  LBS   

Offline Paul New

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Re: 8mm pullies
« Reply #3 on: August 07, 2019, 11:47:29 AM »
Ok 55 on top and a 44 on bottom gives you 25%UD or tons of other ways to get there. But I know most of the manufactured belt guards won’t fit a 60 tooth pulley on the top

Offline gregm784

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Re: 8mm pullies
« Reply #4 on: August 08, 2019, 01:43:04 PM »
... But I know most of the manufactured belt guards won’t fit a 60 tooth pulley on the top

I can get a 58 on top, but unless the belt is SUPER tight, it'll candy stripe the back of it.

On a SBC with a RCD crank support, you can run down to a 53, but you have to relieve the I.D. of the lower pulley a tad bit. 
Greg
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Offline dreracecar

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Re: 8mm pullies
« Reply #5 on: August 19, 2019, 05:37:39 PM »
OD% (or Under) only equates to how soon the blower reaches full boost before it starts to cavitate.   5 over made the same boost as did the 18 over, but was a rocketship at the hit with the 18%