[jivepepper]

I'm changing my dampner from a 6.75" to an 8" ( I think the rib area actual measures a tad less than 8) 18% overdrive pulley and the SC pulley from a 2.8' to a 3".

Right now I use a 106.5" belt. How could I calculate the new belt size I need?

[hardhitter]

Use string and measure it?

[jivepepper]

oops

[jivepepper]

Originally Posted by hardhitter Use string and measure it?

That wouldn't allow for the amount for the tensioner's travel.

I got a 108.8 inch to just squeeze on there. This is how I estimated it.

My old belt was 106.49 so going by that, this what I came out with.

Size of old crank pulley 6.75 x 3.14 x .55 . The approximate of amount of belt wrap on the crank pulley is 55%. on the 2000-2004 and about 70% in the 96-98's.

This is the number i came up with by using the circumference of the pulley then subtracting the amount that's not cover by the belt. About 45% was not covered.

So with this info I came up with 11.65 inches of rap on the old crank pulley.

Then do the same with the new pulley 7.85" x 3.14 X .55%

The answer is: 13.55

So then I subtracted 11.65 from 13.55 and came up with
1.9" of more belt needed for the larger crank pulley.

Of course I did the same with the new SC pulley. Accept it had about 75%of belt wrap on it.

Old one was 2.8" X 3.14 X .75 = 6.59" of belt wrap

New SC pulley 3" X 3.14 X .75= 7.06" of belt wrap

So I need .47" of more belt

106.49" old belt
.+1.90" Needed for new oversized crank pulley
.+0.47" Needed for new SC pulley.
-----------------
108.86" Of belt needed

So my 108.8" belt was almost right on the money. I can learn something new almost every day.lol

[HMUSN]

double post ftl.

[jivepepper]

Originally Posted by HMUSN double post ftl.

I made nice little write up there. Over look the dp.