under drivepully ?

hawk

Registered User
Hey guys, can someone tell me the best type , size and place to buy the underdrive pully set. Also what size MAF came on the 89 t/bird and whats the best size to get with out changing injecters.
hawk
 
hawk said:
Hey guys, can someone tell me the best type , size and place to buy the underdrive pully set. Also what size MAF came on the 89 t/bird and whats the best size to get with out changing injecters.
hawk
Do a search for underdrive pulleys. There are several places they can be purchased and aluminum ones will give you a little more bang for the buck. Three vendors that come to mind are SCI, SCP and ASP. Not sure if March still offers them.
 
I notice no gain in horse power when I installed underdrive pullies.
I did get small amount of gain in horse power from the over drive
to the jackshaft on my under drive chankshaft pulley.

I would spend my money some where else than on underdrive pullies.
Unless you able to find underdrive pulley set with a overdrive
crankshaft to jackshaft pulley.

RANDY
 
Randy N Connie said:
I notice no gain in horse power when I installed underdrive pullies.
I did get small amount of gain in horse power from the over drive
to the jackshaft on my under drive chankshaft pulley.

I would spend my money some where else than on underdrive pullies.
Unless you able to find underdrive pulley set with a overdrive
crankshaft to jackshaft pulley.

RANDY
I don't understand how you didn't see a gain, but maybe you didn't notice it. UD pulleys were one of my bigger bang-for-the-buck mods on my car. But like you said, an overdrive jackshaft is nice.
 
If I do the UD pulley mod, will it affect the blower speed?

I am already over driving my blower by 10% with a 5% JS and 5% blower pullies......
 
Underdrive pullies

I would say the underdrive pullies are decent way to regain a little power lost to your accessories. I would just warn you that if your charging system or battery are weak, or you have a high powered sound system you may have issues with low voltage.

Charles
 
thanks guys.

Thats all a big help, what about the size MAF that came on the 89 sc, and the best size i can go to without changing injecters?
 
+10% Crank with Underdrive Serpentine

Randy N Connie said:
Unless you able to find underdrive pulley set with a overdrive crankshaft to jackshaft pulley. RANDY
A couple of weeks ago I suggested a 2 piece crank pulley to Charles Warner of MP. Stock OR 10% Crank - JS pulley, and Stock OR Underdrive serpentine pulley. Could mix & match what you want.

I would buy a 10% crank with underdrive serpentine. I already have an underdrive serpentine on my car. I don't want to give up my underdrive, for the sake a 10% crank.

68COUGAR
 
2 peice crank pulley would most likely increase weight.

On my stang I got a verified 12rwhp with UD pulleys. The SC crank pulley is very hefty and I figured just teh change to aluminum would be an asset.

I barely noticed 12rwhp on my stang and it weights alot less then the SC just for reference
 
The largest percentage gain you will receive from underdrive pullies,
would be from the lighter weight, if made of aluminum.underdriving
the acc would be the smallest percentage..Of any rwhp gain from
UD pulley set.

The best pulley buy, ( bang for the buck) For power gain from pullies.
Would be the purchase of a aluminum jackshaft and or blower pulley.

Randy
 
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thanks guys.

You have all been a big help, now all i have to do is research what a jackshaft pully is haha. live and learn from those who know more is my motto. and the guys who know more are you guys.
thanks again
hawk
 
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