Underdrive pulleys

[White-V-6-S-Ten]

What ones would you guys suggest and can you also put links to them please! Also what about the belt for them.
Thanks!

[12sws27]

March pulleys.
http://store.summitracing.com/partdetail.asp?CP=1&part=MCH-4460&N=700%200&Ntt=MCH~4460%20or%20SPE~4460&Ntk=KeywordSearch&rsview=sku&Ns=

[12sws27]

Oh and March suggests a belt size. I forget the size I used. I'm sure you can find the info on here somewhere though.

[Boatz]

What are the gains and losses using underdrive pulleys?:confused:

[12sws27]

What are the gains and losses using underdrive pulleys?:confused:
It'll free up a little power. It's easier to turn a smaller pulley that it is a big one. It might give you 3-5hp. Should win you some better fuel milage too. I don't think there is ant down side with the March pulleys. Atleast not that I can think of.

[White-V-6-S-Ten]

Dont you need an impact to take the pulley off the alt? or is there another way to get it off?
What about tightening the pulley back on the alt after replacement???

[Boatz]

It'll free up a little power. It's easier to turn a smaller pulley that it is a big one. It might give you 3-5hp. Should win you some better fuel milage too. I don't think there is ant down side with the March pulleys. Atleast not that I can think of.


Thanks for the info... I will add to my wish list...:propeller

[12sws27]

Dont you need an impact to take the pulley off the alt? or is there another way to get it off?
What about tightening the pulley back on the alt after replacement???
There's a aplace to put an allen or torx wrench to hold it from spinning. Then you can just use a wrench. Thats how I did mine. The smaller pulley makes it a little harder to get a wrenh on the nut but you can still do it. I have no air tools.

[White-V-6-S-Ten]

Nice! Good deal So i can do it by myself!
How did the crank pulley go? I have heard some dont fit right, That the bolt holes need to be rodded out so it fits.
Would summit know what size belt i would need or would i need to call march?

[Bone Crusher]

crank pulley goes on fine....I had to use a long breaker bar and build up some momentum and then jerk it counterclockwise to break the 3 orbit bolts and the central bolt.

[12sws27]

The instructions the pulleys come with will have the suggested belt size. Maybe Chris remembers the belt size he used, Chris? :)

[Bone Crusher]

Hey man I just popped it on without even thinking

[DiCi21]

I just put these on my truck and love them. I think they make a noticeable difference the engine seems to rev quicker. As far as taking the old pulleys off i had a hell of a time getting the alt pulley off. I ended up taking it out and impacting the nut off. The crank pulley was easy tho. For belt sizes march recommends a 91 inch belt. However that was too small so i exchanged that for the next size up which was a 92.3 inch belt and that fits perfectly.

[Bone Crusher]

like I said its a 92.3 inch belt...LOL

thx Matt

[12sws27]

You know there's something about a 98 that is different. I think the idler in a little smaller or something. I noticed that whn I swapped my Wynjammer from my 2000 to my 1998.

[White-V-6-S-Ten]

So the big bolt that holds the ballancer on has to come off?
Should i use lock tight on those bolts as well? or just torque them?
What would be the spec if i did torque them?

[White-V-6-S-Ten]

What would your guy's estimate be for gains by putting these pulleys and an electric fan on?
I already have the ls1 electric fans they just arent on i need to get the wireing set up for them.

[White-V-6-S-Ten]

http://www.autopartswarehouse.com/shop_parts/performance_pulleys/chevy/s10.html
Whats the difference between these... The jet pulleys and the march pulleys?
Other than the price?

[12sws27]

So the big bolt that holds the balancer on has to come off?
Should i use lock tight on those bolts as well? or just torque them?
What would be the spec if i did torque them?

IIRC it does. It's really not that hard to do really. There much harder tasks. Don't worry to much. I'm sure you can do it in under 3hrs. It could be done in 1 it stuff goes smooth.
I just tightened them down real good. I didn't even put a torque wrench on them. Even though I have one. IDK what the torque spec is.


What would your guy's estimate be for gains by putting these pulleys and an electric fan on?
I already have the ls1 electric fans they just aren't on i need to get the wiring set up for them.
I hear 10hp is common with te fan and I'd guess 3-5 on the pulleys. You wont "gain" power BTW, these mods free up power.


http://www.autopartswarehouse.com/shop_parts/performance_pulleys/chevy/s10.html
Whats the difference between these... The jet pulleys and the march pulleys?
Other than the price?
I don't know about the others but March's kit has the smaller alt pulley so you wont lose alternator output. The other kits might have started doing it to, IDK.

[White-V-6-S-Ten]

[quote=12sws27;224192]IIRC it does. It's really not that hard to do really. There much harder tasks. Don't worry to much. I'm sure you can do it in under 3hrs. It could be done in 1 it stuff goes smooth.
I just tightened them down real good. I didn't even put a torque wrench on them. Even though I have one. IDK what the torque spec is.


What does IIRC mean?

[12sws27]

[quote=12sws27;224192]IIRC it does. It's really not that hard to do really. There much harder tasks. Don't worry to much. I'm sure you can do it in under 3hrs. It could be done in 1 it stuff goes smooth.
I just tightened them down real good. I didn't even put a torque wrench on them. Even though I have one. IDK what the torque spec is.


What does IIRC mean?
If I Recall Correctly

[DiCi21]

according to the description of them on summits website... "March Performance Late GM Power and Amp series pulleys are designed to give superb performance, while maintaining perfect electrical charging, even at idle. They create about 11 hp at the rear wheels by reducing accessory drag. These pulley kits are ideal for vehicles with high amperage needs, such as towing or heavy stop-and-go driving." I'm not saying that is 100% true but its definitely noticeable