i'm looking for some underdrive pulleys, but summit has nothing, and neither do any of my local shops.

i know theres a bunch of you with them, so where do i get them from?

 

aspracing.com

 

thanks dale, any ideas where i get a new belt for it?

 

you do what I did when I had the 3.4 swapped in, trial & error.

OR

find out how much percentage bigger/smaller the pulley's are from stock, and adjust for the new belt. yes,it does involve math

 

yep, gotta bring out the old calculator and do the math

 

summit didnt list any....boy thats funny thats where i got mine

got a crank and alternator pulley for like 60 bucks maybe they dont carry it anymore who knows. call back and ask someone else some of those guys arent to smart

 

Kretos, I bought my ASP pullies from Summit also.

I will preach again and I speak from 1st hand experimenting with the pulleys and 3 different size alts (108amp, 140amp and 200amp) Do not use the alternator underdrive pulley! Just buy the crank underdrive pulley. I could not even use my 200amp alt with the alt underdrive, it still discharged at idle. The alt just does not turn fast enough at night with the headlights on, the alt pulley reduces the revolutions too much.

Here is a link to belt info.
https://www.thirdgen.org/techbb2/sho...ight=ASP+crank

Reduce your current belt length by 2" if installing an ASP crank underdrive pulley.

 

thanks, just outta curiousity, i'm thinking of ripping out the air and smog pump, am i looking at any ill effects?

 

Yep, your car will have more power do to having to turn less rotation mass. Thats the kind of ill affects I think you don't mind though

 

is it really gonna effect my emisions?

i wouldn't think it would affect much, but who knows?

 

in a 3.1l do you need the smog pump replacement pully to pull the smog pump? The way the belts are you can't just bypass, you gotta reroute the belts.

 

nope just pull the pump plug anything that needs to be pluged and messure for the belt length, simple as that....at least for the smog pump. i still like being cool in the summer =) so air is still in, for now

 

3.1 belt system
removed smog
underdrive crank

I had to make a custom alt bracket to make my belt tight enough.

 

I tried skipping the air and the belt rubbed on the waterpump pully so I need a replacement pully for that I'm guessing. I would like to bypass it though since my a/c needs to be recharged anyways, would rather just dump it.

 

Nocturnall, the 3.4 power steering pump bracket sits it a little higher then the 2.8/3.1 bracket. Might want to look into that as someone else on here has done this.

 

Couldn't you also just take a rope, tie it around the original pullies and then mark it? Then install the overdrive pullies, tie the rope around again, and mark it a second time, and then just go by the difference of the two marks?

(By doing a before and then after measurement, the lack of tension on the tensioner shouldn't matter- if that made sense )

 

You all forgot Jet they make a set of underdrive pulleys for our cars.

 

I know jet makes them, but I refuse to buy from jetchip anymore.

 

i didnt look at the other places, what kind of prices they have, but you might want to check these guys out, they make an UD pulley for the 60*v6

http://www.fastfwdperformance.com/

 

cool link. Wonder if FWD crank pully is same as RWD?

Surprised they dont make anything for the GTP's yet, thats kinda why I looked

 

i would imagine it would be the same for all 60*v6's..



yeah the aftermarket for w-bodies is extremely limited, i used to have a cutlass but fried the tranny, never got a chance to soup it up.. heh..

 

i'm wondering this too, you'd think its all the same, but hwo knows

 

Summit has them, you just have to search under the part number. A general search will not pull it up! they were out of stock when i ordered. I think I order direct from Asp...

 

We aproximated. Put on the original belt after the install of the new parts. I pulled the tensioner to get anidea where it needed to be to do its job. Joe then pulled up the slack i the belt and measured. Then bought about 5 belts till we got the right one and returned the rest. Autozone barely had the right size. My car is a non smog car. It also did not come with a factory idler pulley. I had to get a junkyard one and install it. Otherwise I was having belt issues. The smallest belt would not fit w/o slipping.

I only installed the undrive crank pulley. But the alt still would not keep up with the Factory pulley. So i wanted a nicer Billet pulley anyway...installed the smallest alt pulley from March. Had to have it machined, not enough length on the shaft to fit the nut and lock washer... Hey but its now been working just fine, knock on wood!

Depends on the local laws. I'm in GA, very near the city. My car passes with no Egr or smog pump. And its got a beefy cam, bigger injectors, & high flow cat. Just have to be sure its been run a while first and does not sit. Also the timing has to be set to 10. It even passed with the 3.4. they put it in as a 3.4!

 

that was why we had to go to the darn GM idler pulley

 

thats good to hear, we have fairly lax emmisions up here

 

Do you happen to have a part number on the smaller pulley. Was it for a v-belt? Thanx

 

March’s Alternator Fan (MCH-221) and pulley w/ cover (MCH 112).

My original March pulley was the diameter of the stock pulley and was not charging enough. This one is the smallest that March has, I believe, and it did the trick for me! Hey and it even looks pretty too!



But like I said I had to get a shop to machine the center down slightly since the shaft on my alternator was not long enough to accomidate the lock washer. Then we added blue loctite to be sure there was no chance of it letting go, but so we could still get it apart!