UDP w/ electric steering

[h018871]

I installed a 25% underdrive pulley last night and discovered that the belt lengths are different for cars with electric power steering.

Factory belts
Main (alternator/water pump): GM 12642400 / AADJ / 6PK2060 ~ 81.10"
AC: GM 12651325 / AABN / 4PK982, ~ 38.66"

what I ended up with after a trip to the local parts store
Main: 6PK2020 ~ 79.53"
AC: 4PK0890, ~ 35.04"

[rich3fan]

Good to know, thanks. I was told the only belt that was a different size was the A/C belt. I'd still like to know if under driving the electric P/S pump (or unit, don't even know what it looks like) will have any adverse effect on it.

[That_Guy]

Originally Posted by rich3fan

Good to know, thanks. I was told the only belt that was a different size was the A/C belt. I'd still like to know if under driving the electric P/S pump (or unit, don't even know what it looks like) will have any adverse effect on it.

There is no pump, it's electric

[h018871]

There're a bunch of posts regarding pros and cons of the UDP. Since I have a cam, my idle is ~850, so the alt and WP are not turning too slow.
Electric steering only adds to the load on the alt and battery

[rich3fan]

Yes, I started one of those threads. I've also discussed UDP's with LGM about one brand over the other. On big power apps, Fluidampr pulleys will need to be rebuilt, Powerbond isn't much more beneficial over the stock pulley from a harmonics dampening standpoint, and ATI and ASP are other considerations. Now that it sounds like the electric power steering is a system completely separate from the accessory drive, that question is answered.