Whats to gain from an underdrive pulley?
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Joined: Nov 2002
Posts: 1,201
From: Somewhere between a shotgun barrel, and a blood spatter on the wall.
Whats to gain from an underdrive pulley?
i was peakin around summit for anything for my car cause i got $20 summit cash... haha (its a weakness) and i saw 4 or 5 different underdrive pulleys from $200-$270...
how much help is that really gonna get you?
how much help is that really gonna get you?
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Joined: Sep 1998
Posts: 8,319
From: US 1 Mile Marker 52 in the Florida Keys
Re: Whats to gain from an underdrive pulley?
first off make sure they are for the LS1.
there are only a few that i know of. they have to be the pulley/balancer combined. not a piggyback like the LT1.
it's hard to say what the real world gains are. i added mine with several other mods, so it was hard to tell. some say they can notice a quicker rev up since it takes less power to spin everything.
but it's very possible that it is mental.
there are only a few that i know of. they have to be the pulley/balancer combined. not a piggyback like the LT1.
it's hard to say what the real world gains are. i added mine with several other mods, so it was hard to tell. some say they can notice a quicker rev up since it takes less power to spin everything.
but it's very possible that it is mental.
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Joined: Jan 2005
Posts: 2,592
From: N Falmouth MA
Re: Whats to gain from an underdrive pulley?
Originally Posted by frmula1
i was peakin around summit for anything for my car cause i got $20 summit cash... haha (its a weakness) and i saw 4 or 5 different underdrive pulleys from $200-$270...
how much help is that really gonna get you?
how much help is that really gonna get you?
Anyway. I believe that there was a test done in GMHTP mag, under "Project Blue Thunder" they installed the underdrive pulleys in a TPI 305.... They picked up around 20 hp. The HP gain is achieved from less parisitic draw on the motor to run the accessories. I have also heard of the belts having a tendancy to "walk-off", SLP sells a "high-wall" version..
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Joined: Sep 1998
Posts: 8,319
From: US 1 Mile Marker 52 in the Florida Keys
Re: Whats to gain from an underdrive pulley?
50k miles on the UD pulley on my IROC and never lost a belt
20K miles on my LT1 and never lost a belt
10K miles on my LS1 and threw a belt once...in the driveway on startup.
takes 3 mins and a 15mm wrench to put i back on
20K miles on my LT1 and never lost a belt
10K miles on my LS1 and threw a belt once...in the driveway on startup.
takes 3 mins and a 15mm wrench to put i back on
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Joined: Nov 2000
Posts: 1,148
From: AZ
Re: Whats to gain from an underdrive pulley?
Originally Posted by Antz97ZNJ
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Joined: Nov 2000
Posts: 1,148
From: AZ
Re: Whats to gain from an underdrive pulley?
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Joined: Mar 2005
Posts: 792
From: Long Island, NY
Re: Whats to gain from an underdrive pulley?
I have the asp crank and alternator pulley on my 3.1.Noticed pretty decent gains for the money.Do not get the alternator pulley unless your audio system is stock.
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Joined: Sep 1998
Posts: 8,319
From: US 1 Mile Marker 52 in the Florida Keys
Re: Whats to gain from an underdrive pulley?
"Do not get the alternator pulley unless your audio system is stock."
don't you mean NOT stock??
the ud pulley drops the charge amount a little, but it is adequate for a stock stereo. now if you have amps and big speakers...you'll need the juice from the alt.
don't you mean NOT stock??
the ud pulley drops the charge amount a little, but it is adequate for a stock stereo. now if you have amps and big speakers...you'll need the juice from the alt.
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Joined: Dec 2002
Posts: 821
Re: Whats to gain from an underdrive pulley?
Originally Posted by teke184
"Do not get the alternator pulley unless your audio system is stock."
don't you mean NOT stock??
the ud pulley drops the charge amount a little, but it is adequate for a stock stereo. now if you have amps and big speakers...you'll need the juice from the alt.
don't you mean NOT stock??
the ud pulley drops the charge amount a little, but it is adequate for a stock stereo. now if you have amps and big speakers...you'll need the juice from the alt.
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Joined: Jan 2005
Posts: 2,592
From: N Falmouth MA
Re: Whats to gain from an underdrive pulley?
Teke184--I've never actually heard of someone complaining of thrown belts. It might be one of the SLP "hypes". I'm just going by what I've gathered...
I'll print up the GMHTP mag article w/ dyno results...Not trying to argue....I'll post it and you guys see what you think...
I'll print up the GMHTP mag article w/ dyno results...Not trying to argue....I'll post it and you guys see what you think...