Belt Cross # Please

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BSouders80

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I'm running an 8 rib whipple setup and currently have a continental 4081258 on it.

I want to change over to a gates belt. I believe the Gates part number that the 4081258 crosses to is the Gates K081265. Can someone confirm that is correct?

I would really like to put a Gates RPM series belt on it, but need help figuring out that part number.

Any advice would be much appreciated.

Thanks.
 

MTF

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@BSouders80

The first two digits are model number, the third number is the rib count, the last four digits is the length of the belt.
So, your Continental belt is 125.8 inches long, the Gates belt is 126.5 inches long.
Your belt tensioner will not absorb almost .7 inch of belt length.
A 1/4 to 7/16 in length difference you should be able to get away with.
You would have to play with idler pulley/pullies and increase them in size to make up the .7 (almost 3/4") of an inch the Gates belt is longer.
 
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BSouders80

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Dayco and Goodyear have a belt that is 126.00" long. Do you think that would be worth trying?

Dayco 5081260 and Goodyear 1081260

Livernois seems to think it's with how the engine behaves when it hits the rev limiter. They have an update to the tune they're supposed to be sending soon.

I thought the RRR Racing PM-1002-76 tensionser would help. BUT - Livernois has included that in their 8 rib pulley set. Already have that installed. So if Tension is good. RRR Idler is supposed to be around 50 ft/lb, where factory is around 35 ft/lb. Pullies are good and aligned. Verified with a laser. Maybe the redline is what's causing it. That is when it's happened both times to me. Maybe it's something with so much rpms under a hard load and then the shock of stopping the power with the rev limiter.

We shall see.
 

Skubik

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I'm running an 8 rib whipple setup and currently have a continental 4081258 on it.

I want to change over to a gates belt. I believe the Gates part number that the 4081258 crosses to is the Gates K081265. Can someone confirm that is correct?

I would really like to put a Gates RPM series belt on it, but need help figuring out that part number.

Any advice would be much appreciated.

Thanks.
Yes that’s the same belt I’m using on my 8rib setup. Stay away from the 126” Goodyear belt, I shredded two I think bc they’re for oem application and not for performance who knows stick with gates no issues ever. I recently had to replace my idler pulley and the replacement was a bit bigger so I went up to the gates HD fleet belt 126.5” to offset the bigger pulley size
 

Skubik

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Gates K081253 is what I was using with no issues, it’s right under 126”
 

Skubik

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I just went up on size by half inch to this belt Gates

K081265HD​

So far so good, I adjusted tension with the the adjusting idler pulley. Again I did this bc I went with a slightly larger idler pulley. The billet steel one from Livernois finally died on me, bearings imploded after 5yrs. I went with billet aluminum lethal performance pulley, good part about $90
 

Skubik

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If you actually find the Gates RPM in these sizes please shoot me the part number. I have looked with 0 results. I’ve emailed several performance shops and no one carries it, I don’t believe gates makes an rpm belt in those sizes.
 
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