B&M 250 Blower Smaller Pulley question
#1
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I have a 250 with what appers to be a stock pulley on it i want to go smaller to create more boost but dont want to lunch the motor doing it just a couple of questions.
1. What sizes do they come in?
2. What would be the boost gain of each size.
3. Is it worth getting a smaller pulley in the 1st place.
4. Where do i get them?
I have a 26 ThoroughBred Summer Squall with a Blown 502 obvisoly previosly stated with a 250 B&M Dual quad 650 Holley Double pumpers. I has Stainless Marine Exhaust with 5 in. Elbow and 5 in exhaust out of the transom
1. What sizes do they come in?
2. What would be the boost gain of each size.
3. Is it worth getting a smaller pulley in the 1st place.
4. Where do i get them?
I have a 26 ThoroughBred Summer Squall with a Blown 502 obvisoly previosly stated with a 250 B&M Dual quad 650 Holley Double pumpers. I has Stainless Marine Exhaust with 5 in. Elbow and 5 in exhaust out of the transom
#2
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As good of a deal as you will find.
http://www.offshoreonly.com/classifi...ate=1166736594
You will have to measure your diameter to determine what you need.
http://www.offshoreonly.com/classifi...ate=1166736594
You will have to measure your diameter to determine what you need.
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oop's I left you the numbers on the advertizers site about pulley lbs assuming you had 502's . i have the brochere from b&m if you need more imfo.........
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They say 40 hp per every pound of boost...stock should be 5 pounds and I would only go up to 7.5 max...I'm pretty sure every 1/8" decrease in diameter is a pound
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Thanks car ur probably right about the 7.5 thats a lot of pressure and heat plus i dont have an inter coller yet either thats next winters project along with nice flowin aluminum heads=)