SN89 belt number/size

[steel1]

Anyone know a part#/size belt I would need for my SN89 set-up? It's going on a 93GT Mustang with 6" crank/4" s/c pulley. I am piecing together this kit and getting down to the final few components!

[steel1]

forgot to mention, it's a 6-rib set-up.

[JPJP]

I am running a 3.75 Dia. pulley w/ the stock 6" Dia. crank pulley and am using the 48.5" long belt. It barely fits. I believe this same belt will work nicely with your 4" Dia. S/C pulley.

I recommend you use the Gatorback brand belt as I have been told it holds better than other brands.

[JPJP]

I just put the belt on again after rebuilding my SN-89. The 48.5" belt barely fits over pulley to get it on. You may actually have better success with the 49" long belt since you are using a 4" Dia. pulley at the unit.

Let us know what you used as there is a manufacturing variance in the belt lengths.

[steel1]

Thanks JPJP 49" belt fit perfect with my set-up. I used a Gatorback 49" belt $18 from summit. I also had to get a shorter accessory drive belt, went from stock 90.5" to 90". Needed to do this because the stock belt would lay on top of the wp pulley when installed under the tensioner.

[JPJP]

I had a similar issue w/ my '86. The W/P pulley is bigger (underdrive) and the accessory drive uses a stock length belt of 92.3". I wound up using a 91.5" long belt for my set up.

[JPJP]

Oh one thing to watch steel1: since you are running almost as small a pulley as me...keep an eye on that fluid. I noticed since I am running the unit at higher RPM's the fluid breaks down at a faster rate.

[steel1]

Good point about the fluid, I filled it with B&M trick shift and the fluid is such a transparent blue color it's hard to see on the stick. My Mustang is only a weekend/nice weather cruiser and only sees about 750-1000 miles a season, but your right frequent fluid changes are a must.