I got ahold of an asp underdrive balancer pulley not the add on.Its 23% or 24% instead of the 34% I think the add on pulley is.Do I need to bother running an overdrive alt pulley I got one with the set but if its not necessary then won't run the overdrive pulley.
Its a pain as you need different belt to run the overdrive alt .
I have stock stereo and don't plan on upgrading the stereo in that car.

So who's running one in their auto and do I need that overdrive and realize the cheaper underdrive is higher underdrive so mabye with that one the overdrive alt might be more useful.

 

When I had the march crank pulley I had charging problems, back then I used the car more often and drive in stop and go traffic with AC on. The MBA OD alt pulley solved the charging problem.
You could be good without the OD pulley, depends on where and how you use the car. Try it out without the alt pulley and see how it charges, if it doesn’t work well you can slap that pulley on.
A new (smaller) belt is need with UD crank pulley, but chances are you’ll be fine with the same belt when you put on that smaller alt pulley.

 

If you are talking about the asp alternator pulley it is underdriven by 15% and not overdriven. It will slow down the speed of your alternator, not speed it up. The asp pulley is bigger than the stock alternator pulley and is all black.

 

If you go to the asp website and scroll down past the undrive alt and underdrive balancers and add on pulleys you will find their overdrive ones.Mine is overdrive and black and smaller than stock pulley.So its just do I need it with the less underdrive balancer with my auto which is mostly city driven,stock stereo but would use the air once in awhile.
I may just return the belt I got to use with just the underdrive and get the one asp says I need with the overdrive alt.Don't want to have any charging problems just thought not using the overdrive alt would give a bit more benefit.The lt1 dont have as much stuff driven off the belts as the ls1s and other cars but reduced weight of the underdrive balancer over stock might give some gain in rpm quickness and maybe hp too.

 

mine works fine and electrical stuff is perfect with the 23% asp and the stock alternator pulley. I wouldnt reccomend an overdrive pulley unless you have some aftermarket electrical stuff like stereo or what not.

 

Nice car MarkyMark,checked out your website!! So you have the exact same pulley and no problems.Do you run air quite a bit and drive a lot of city and not much highway like me? I guess throw the balancer pulley on and monitor things ,I have that overdrive and can put it on at any time.

Oh curious is that 3400 weight with full tank or what.My 96 is a vert and weighed 3615 the other day full tank and with jack and spare tire out.I have subframe connectors,shock tower brace was in the car also.

I ran a best of 14.3 at 96mph with 2.18 60ft on nitto drags but our track wasn't prepped that day.Its also 1900 feet altitude.For mods I had magnaflow catback ,airfoil,tb bypass,g2 induction,holley filter,hpp tuning out and maf translator.Oh and 3.42 gears.My raceweight with 1/2 tank was 3800.I weighed 250 at the time..am 220 now.

This years mods are 2800 vigilante and that asp underdrive waiting for install.
I also have 1.6 pro mags and CC305 but may wait to get some mac headers and some LE 2 or equivalent heads and do the heads,cam and headers all at once.
I also have a zex kit waiting for install.And might get a few little things,racetronix pump,some 30 svos and a 58 or 52 tb. I sold the nittos and have some old very old bfg drags to try at the track but buddy bought new et street radicals so borrow them for a couple of runs and then buy some next year likely and get some nitto drags for the street.Last pair of nittos was flatspotted from sitting almost two years on buddies 97.

You will like the gears they make the car much more fun to drive and my best before them was 15 flat and before the magnaflow at 94 mph.Also 60fts on street tires were around 2.40s.

Anyway thanks for the heads up since you have the same balancer.Not that many people have them as they seem hard to get.I got mine used on the board and had to wait a long time for it.I had an add on one on my last 97 ta and it seemed to add vibration so went with the pulley this time.I guess you don't have know if it did take off a tenth or so or did you test before or after the pulley.I am likely installing the vig 2800 and the pulley at same time and then will hit track next month.I am hoping for a 13.5 with a 2.0 60ft.That would be around 13.2 corrected approx for my altitude.And like you would hope for a low 12 on spray and into the 11s on spray with my cam and rockers and deep 11s with heads and headers..

 

that 3400 weight was just a guess....i really dont have much of an idea.
My car is a non ttop car, with the following removed: spare tire, jack, back seats, air/egr equipment, front swaybar, deleted traction control, and soon to be deleted and removed abs system when I get my header install done.....which I'm still in the middle of. Yea I am excited about the sotp and better acceleration of the gears, the 2.73's I have now are dogs. I dont really have any before and after times with the asp, but I was running mostly 13.7's to 13.8's without it and with it is more around 13.6 to 13.7's. Car felt stronger to me, idle a little better, revved a little quicker, and shifted smoother.