underdrive belt size??

[gjp]

I just found out today my truck has underdrive pulleys. Yuck! The stock replacement belt is too long. I cannot read the writing off the old belt. Anyone know the length of the belt with underdrive set-up. I guess I can just match it up at napa. The maintenance paperwork I got when I bought my truck does say underdrive pulleys installed back in 1995.

 

[attackdog]

Re: underdrive belt size??

What advantage do you get with an underdrive pulley kit and were would you purchase a kit?

 

[gkrcr882]

Re: underdrive belt size??

Theoretically it slows down the accessories and frees up some horsepower:2cents:

 

[gjp]

Re: underdrive belt size??

Came with the truck. Its suposed to free up like 5hp but it usualy just lowers your alternator output.

 

[QUICK STORM]

Re: underdrive belt size??

i would see if you can get a custom belt made, just measure it.

 

[gjp]

Re: underdrive belt size??

I know napa has a 40mm shorter belt for our trucks. Its the one with no AC according to their website. I think the belt is shorter then that though. Its a ATR underdrive street kit.

 

[Timbo]

Re: underdrive belt size??

Change them back to stock.

 

[Flyin Ryan]

Re: underdrive belt size??

I can't really help with the initial question but would also suggest swapping back to stock.. i've read too many threads on here with people having tons of issues and it ending up being due to the underdrive pullies or someway them being connected to the issues.. plus the possible charging issues with stock alt would tend to scare me off anyways..

I did have charging issues with pullies on one of my previous mustangs.. found out later tht I didn't need one of the fancy three piece sets to get the hp.. just one crank pully doh!

What advantage do you get with an underdrive pulley kit and were would you purchase a kit?

Only place i've seen them is here
http://www.turbotime.us/CategoryProductList.jsp?cat=Syclone+/+Typhoon&offset=90

 

[phoonTy]

Re: underdrive belt size??

Change them back to stock.

I would agree. My truck had underdrive pulley's on it when I bought it. Taxed the electrical system pretty good.

Went back to stock and I really think my truck runs better. Even had a 160amp alternator with the underdrives and it didn't help. I think they killed it prematurely. Went back to stock pulleys, stock alternator and was good to go.

 

[Speed Mafia]

Re: underdrive belt size??

I would agree. My truck had underdrive pulley's on it when I bought it. Taxed the electrical system pretty good.

Went back to stock and I really think my truck runs better. Even had a 160amp alternator with the underdrives and it didn't help. I think they killed it prematurely. Went back to stock pulleys, stock alternator and was good to go.

i would do 2 things! one get a stiff peace of wire or something that will not stretch and run it along the system setup and then measure it end from end and there you go you know how long the belt is or it will get you close!

2nd call the pully company and get the belt length or really any pulley company will have that setup and belt length :2cents:

 

[QUICK STORM]

Re: underdrive belt size??

i would also agree on switching back to stock pulleys, could help you misfire out to! you never know.

 

[SY2455]

Re: underdrive belt size??

I have the underdrive pulleys on mine and the paper work that came with them said to raise the IDLE RPM up to 900rpm to avoid electrical system problems. And mine works great. The belt you need if you are using the crank and alternator pulleys is Gates Micro-V # K060915. You need to check the 060 as these # are hard to read.

 

[gjp]

Re: underdrive belt size??

Thanks. Thats why I said "Yuck" in my first post. I do want to go back to stock. What pulleys were changed? I ask this question a while back when I first bought the truck about pulley sizes. It idles at 13.5-13.6 volts.(phil chip idles @750rpm) wot it wont go lower then 13.2volts. I will switch back. I kept the new stock belt for when I buy the pulleys. I need the crank & alt pulleys?

 

[SY2455]

Re: underdrive belt size??

If you want to go stock, stop by pick your part and get the crank and alt pulleys from any 4.3 s-10 1988 thru 1992. If it were me I would look into having phil raise the idle up to 900 rpm you might like it.

 

[gjp]

Re: underdrive belt size??

napa sized up the belt. The guy in there knows me by name. Fits good. I will get the new pulleys later after I am done playing with my engine. Thanks guys. Just so I dont have to start another thread...WHO MAKES A GOOD HEAD GASKET SET?? I heard our GM stock sets are prety good.