Help! Main and AC Belts cannot find!
Thread Starter
Burning Brakes
Joined: Apr 2012
Posts: 837
Likes: 215
From: Springfield PA
Help! Main and AC Belts cannot find!
Hey guys I am about to do a cam swap and will be using an SLP 25% UDP. The belt numbers from slp directly have been known to be wrong, and I am seriously confused at what belts will work. I do not want to order belts to just have to return them.
So pretty much what sizes should I look for for my 99 c5 ls1 with an 25% UDP and stock size idlers!
So pretty much what sizes should I look for for my 99 c5 ls1 with an 25% UDP and stock size idlers!
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 301
From: Columbia SC
The circumference of a pulley is Pi times the diameter, or Pi times 2 times the radius. This measurement should be from the actual base/bottom of the belt pulley grooves. Assuming the belt goes around 180 degrees of the pulley then the "added" belt length of the stock pulley size would be half of that. Calculate the same amount for the undersized pulley and determine what reduced belt length you are creating. Subtract that from the actual stock belt length. If the belt goes around less than 180 degrees of the pulley you can just ratio the smaller partial circumference change instead of 1/2. Hope this helps, if not just PM or email me with your phone number and we can discuss.
PS: You should be able to measure the original belt length or get it from any manufacturers web site. Let us know how it works out for you. I provide a money back guarantee on all my guidance.
PS: You should be able to measure the original belt length or get it from any manufacturers web site. Let us know how it works out for you. I provide a money back guarantee on all my guidance.
Last edited by dadaroo; Dec 23, 2013 at 12:41 PM.
Pro
Joined: Sep 2008
Posts: 660
Likes: 16
From: Tustin California
Take string that isn't "stretchy" and carefully wrap it around the pulleys exactly as the belt would ride. Cut it and measure it. Most belts have the length on the package or in the book at the auto parts store. Just make sure you don't make the belt unreturnable in case you need to go up or down a size. Rod
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
Take string that isn't "stretchy" and carefully wrap it around the pulleys exactly as the belt would ride. Cut it and measure it. Most belts have the length on the package or in the book at the auto parts store. Just make sure you don't make the belt unreturnable in case you need to go up or down a size. Rod
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 301
From: Columbia SC
PS: I recommend you go with Gatorback belts. Many people have experienced belt squeal with other various brands. Seems like some brands have deeper belt grooves that allow the belt tips to ride/touch the pulley groove bottoms thus making noise.
Thread Starter
Burning Brakes
Joined: Apr 2012
Posts: 837
Likes: 215
From: Springfield PA
Thanks for the advice, I cannot fathom it is this hard with so many varying part numbers....the numbers apparently are wrong from SLP, the local store doesn't carry gates, and when I type in a recommended one on amazon says will not fit my vehicle...ugh.
Bump for someone using the slp/power bond 25% UDP for part numbers!
Bump for someone using the slp/power bond 25% UDP for part numbers!
Pro
Joined: Sep 2008
Posts: 660
Likes: 16
From: Tustin California
There have to be 100 guys who have done this. Hopefully some one will chime in on the belt number they used. And yes the tensioner must be at 2/3 or more but not tight when measuring the string. I thought that didn't need mentioning. Rod
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Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,840
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
I used a 4PK1015 4PK = 4 rib 1015 mm = 40 inch for the AC belt
I used a 6PK1930 6PK = 6 rib 1930 mm = 76 inch for the drive belt
4PK1015 = 5040400DR
6PK1930 = 5060760DR
Good luck
Bill aka ET
I used a 6PK1930 6PK = 6 rib 1930 mm = 76 inch for the drive belt
4PK1015 = 5040400DR
6PK1930 = 5060760DR
Good luck
Bill aka ET
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 301
From: Columbia SC
[QUOTE=boostedfury;1585750075]Thanks for the advice, I cannot fathom it is this hard with so many varying part numbers....the numbers apparently are wrong from SLP, the local store doesn't carry gates, and when I type in a recommended one on amazon says will not fit my vehicle...ugh.
And WHY would you expect a nonstandard size belt to show as a correct fit for your car?????????????????????????????????
And WHY would you expect a nonstandard size belt to show as a correct fit for your car?????????????????????????????????