Serpentine belt 1994 Ultra

I'm looking for a new belt for my '94 Ultra and came across the fact that there are two lengths listed for the alternator/PS belt: One for the '1st design' and one for the '2nd design'.

What are these design differences?

Not sure of a first and second design.......your belt should have a number on it that can be cross referenced.....

But I thought Ultra's had the SC'd engine? They use 2 belts....

Yes, the engine has two belts, but only the alternator belt seems to have two different lengths. The SC belt doesn't.

I will check for a part no on the belt.

It's also possible that they are talking about an alternator belt for a SC'er engine and a non SC'er engine....

I have run into the two different length thing before. Not sure what is different to cause the need for it though. Each time I have needed the longer of the two belts. You could take yours off and match it at the parts store.

Well I did indeed find the part number on the belt: 24503564.

Turns out that this part is obsolete, and its length does not exactly match the two versions listed in the parts catalogs...

I also found out that the different designs might be related to different alternators that were used in the 1994 model year: The CS130 and the CS144. Since my car has the CS130, I should probably be fine with the 1st design belt. Its length is also closer to that of the 24503564.

Naturally over time, especially if an original belt, that belt can stretch....I think the only difference in the two alternators may be the difference in circumference of the pulleys....but if it was the alternators that caused the difference, the parts catalog would ask which alternator was used, and not label it 1st or 2nd design.....

The trick is replacing the belts.......I think each bracket has a "spacer", that when removed, allows removal of each belt, without removing the mounts/brackets....been awhile since I did one(SC'er).....the regular 3.8 engine has the spacer on the bottom of the bracket....SC'er spacer is near the top(?)....