LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Please explain this picture

Thread Tools
 
Search this Thread
 
Old Feb 22, 2012 | 10:59 AM
  #1  
notsue's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2012
Posts: 120
Likes: 0
From: Fort Riley, Kansas
Default Please explain this picture




Just wondering whats up with the crank pulley and why theres a smaller one thats actually being used.
Reply
Old Feb 22, 2012 | 11:08 AM
  #2  
BIGCAT7274's Avatar
TECH Enthusiast
 
Joined: Oct 2011
Posts: 556
Likes: 0
From: Apopka FL
Default

It's a under drive pulley.
Reply
Old Feb 22, 2012 | 11:15 AM
  #3  
wrd1972's Avatar
TECH Veteran
20 Year Member
Photogenic
Photoriffic
iTrader: (12)
 
Joined: Mar 2006
Posts: 4,668
Likes: 5
From: Central Kentucky
Default

^ yep.
Reply
Old Feb 22, 2012 | 11:29 AM
  #4  
notsue's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2012
Posts: 120
Likes: 0
From: Fort Riley, Kansas
Default

Thank you, that was my guess, but I didnt realize people did that with these... I keep finding new things on this car everyday...
Reply
Old Feb 22, 2012 | 11:35 AM
  #5  
R3DLT1's Avatar
Launching!
iTrader: (5)
 
Joined: Feb 2009
Posts: 245
Likes: 0
From: Bartlesville,OK
Default

Originally Posted by notsue
Thank you, that was my guess, but I didnt realize people did that with these... I keep finding new things on this car everyday...
ha ur just hitting the very tip of the ice berg
Reply
Old Feb 22, 2012 | 11:40 AM
  #6  
bufmatmuslepants's Avatar
12 Second Club
15 Year Member
Photogenic
Photoriffic
Liked
iTrader: (3)
 
Joined: Mar 2007
Posts: 3,280
Likes: 49
From: Hampstead, NC
Default

Take off the big pulley there is no use for it anymore, just adding rotational mass. I have the same thing but I dont get why the hell someone left the stock pully on the outside...
Reply
Old Feb 22, 2012 | 11:40 AM
  #7  
notsue's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2012
Posts: 120
Likes: 0
From: Fort Riley, Kansas
Default

Anyone know why it has two belt grooves?
Reply
Old Feb 22, 2012 | 11:46 AM
  #8  
the impaler's Avatar
Staging Lane
 
Joined: Feb 2010
Posts: 71
Likes: 0
From: republic of texas
Default

The underdrive pulley has no harmonic dampener built into it like the stock pulley does. Removing the stock pulley is a bad idea
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-1

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-2

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-3

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-4

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-5

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-6

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-7

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-8

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-9

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
Old Feb 22, 2012 | 11:48 AM
  #9  
tt383lt1's Avatar
TECH Resident
iTrader: (3)
 
Joined: Nov 2011
Posts: 853
Likes: 0
From: mn
Default

^^ yep
Reply
Old Feb 22, 2012 | 11:51 AM
  #10  
notsue's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2012
Posts: 120
Likes: 0
From: Fort Riley, Kansas
Default

I will more than likely just return it to stock. I'm not really that interested in whatever minor gains I may be getting from it.
Reply
Old Feb 22, 2012 | 12:15 PM
  #11  
3DFORMULA's Avatar
TECH Enthusiast
iTrader: (4)
 
Joined: May 2007
Posts: 625
Likes: 0
Default

thats not a bad idea but it's not hurting anything I don't believe
Reply
Old Feb 22, 2012 | 12:23 PM
  #12  
notsue's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2012
Posts: 120
Likes: 0
From: Fort Riley, Kansas
Default

Sometimes when I'm at idle, my volt meter shows pretty low... and if I have my blinker on it blinks really slow... figured this might have something to do with the alternator. When I'm driving it reads normal, and its not low everytime at idle, but I had been wondering what would make it low ever...
Reply
Old Feb 22, 2012 | 12:26 PM
  #13  
tt383lt1's Avatar
TECH Resident
iTrader: (3)
 
Joined: Nov 2011
Posts: 853
Likes: 0
From: mn
Default

i would pull the under drive pulley off and put it back to stock if it was my car
Reply
Old Feb 22, 2012 | 12:50 PM
  #14  
notsue's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2012
Posts: 120
Likes: 0
From: Fort Riley, Kansas
Default

I have plans to remove the intake and clean it, when I get around to that, I'll go head and remove the under drive pulley and replace it with the stock one. I also plan on taking care of that leaky timing cover, I already feel I know whats causing it... I found an air foil in the TB and removed that, I'm waiting on a new elbow because mine is covered in silicone and still has visible holes... slowly taking her apart and cleaning her up to see what she does by herself... if things are good then heads and cam here I come If things dont look good, then we'll build a motor on the side and put it in when this thing goes.
Reply
Old Feb 22, 2012 | 12:57 PM
  #15  
bufmatmuslepants's Avatar
12 Second Club
15 Year Member
Photogenic
Photoriffic
Liked
iTrader: (3)
 
Joined: Mar 2007
Posts: 3,280
Likes: 49
From: Hampstead, NC
Default

Take off the stock pulley, Ive run a lightweight aluminum underdrive pulley for the past 4 years and not had a single problem, and I spin my motor to 6100 rpm. Ditch the stocker, use the underdrive, it revs noticeably faster without that giant hunk of metal hanging off the front.
Reply
Old Feb 22, 2012 | 12:58 PM
  #16  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 598
From: Jackstandican
Default

Originally Posted by notsue
Sometimes when I'm at idle, my volt meter shows pretty low... and if I have my blinker on it blinks really slow... figured this might have something to do with the alternator. When I'm driving it reads normal, and its not low everytime at idle, but I had been wondering what would make it low ever...
It has everything to do with the U/D pulley. Your battery will be dead w/in a few months if that keeps up. Only way to run a U/D pulley and not kill the battery is never drive in stop/go conditions or run and overdrive pulley on the alternator.
Reply
Old Feb 22, 2012 | 01:04 PM
  #17  
tt383lt1's Avatar
TECH Resident
iTrader: (3)
 
Joined: Nov 2011
Posts: 853
Likes: 0
From: mn
Default

Originally Posted by notsue
I have plans to remove the intake and clean it, when I get around to that, I'll go head and remove the under drive pulley and replace it with the stock one. I also plan on taking care of that leaky timing cover, I already feel I know whats causing it... I found an air foil in the TB and removed that, I'm waiting on a new elbow because mine is covered in silicone and still has visible holes... slowly taking her apart and cleaning her up to see what she does by herself... if things are good then heads and cam here I come If things dont look good, then we'll build a motor on the side and put it in when this thing goes.
did you buy the elbo already. i have a nice one im not using
Reply
Old Feb 22, 2012 | 01:05 PM
  #18  
bufmatmuslepants's Avatar
12 Second Club
15 Year Member
Photogenic
Photoriffic
Liked
iTrader: (3)
 
Joined: Mar 2007
Posts: 3,280
Likes: 49
From: Hampstead, NC
Default

Originally Posted by SS RRR
It has everything to do with the U/D pulley. Your battery will be dead w/in a few months if that keeps up. Only way to run a U/D pulley and not kill the battery is never drive in stop/go conditions or run and overdrive pulley on the alternator.
Dude this is totally false. Like I said, Ive been running a small underdrive pulley and never changed my alternator pulley and I have NEVER EVER EVER had a problem. Your battery is not going to ******* die. Take off the damn stock pulley and run just the underdrive, and it will be FINE.
Reply
Old Feb 22, 2012 | 01:17 PM
  #19  
wrd1972's Avatar
TECH Veteran
20 Year Member
Photogenic
Photoriffic
iTrader: (12)
 
Joined: Mar 2006
Posts: 4,668
Likes: 5
From: Central Kentucky
Default

Originally Posted by bufmatmuslepants
Take off the stock pulley, Ive run a lightweight aluminum underdrive pulley for the past 4 years and not had a single problem, and I spin my motor to 6100 rpm. Ditch the stocker, use the underdrive, it revs noticeably faster without that giant hunk of metal hanging off the front.
I have to respectfully disagree with this. The stock dampener is vital for the long term reliability of the engine but more specifically, the crankshaft by helping to absorb the normal fatiguing resonance that occurs each time a cylinder fires. These resonance might start to degrade the crankshaft over time as well as the main bearings under certain conditions.

This is a vital part for engine longevity because GM spent X amount of dollars to put it on the engine. If it were really not needed, it would not have come on the engine from GM.

I suggest that the OP keep it as is or simply remove the piggyback pulley and use the OEM piece. If he is still wanting to reduce mass and still have the functionality of the crank dampener, then look into the ASP underdrive dampener which is much lighter than stock and much cleaner in appearance.

Above all I think there are very little gains to be had by using either type of underdrive pulley or dampener.
Reply
Old Feb 22, 2012 | 01:48 PM
  #20  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 598
From: Jackstandican
Default

Originally Posted by bufmatmuslepants
Dude this is totally false. Like I said, Ive been running a small underdrive pulley and never changed my alternator pulley and I have NEVER EVER EVER had a problem. Your battery is not going to ******* die. Take off the damn stock pulley and run just the underdrive, and it will be FINE.
Interesting. Mine ******* died six months after putting the pulley on. When the U/D pulley was first introduced there were all kinds of complaints from people of their batteries ******* dying. March did not make an O/D pulley, until they started receiving complaints about batteries ******* dying.
It does depend on your driving habits. If you drive in stop/go conditions where there is not enough voltage to properly charge the battery then the battery is going to eventually ******* die. M6 cars did not have a battery ******* dying problem as much as the autos had a battery ******* dying problem.
Reply



All times are GMT -5. The time now is 05:01 PM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-6
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-7
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-8
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-9
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE