Manual Transmission T56 | T5 | MN12 | Clutches | Hydraulics | Shifters

Indexing a Scattershield

Thread Tools
 
Search this Thread
 
Old Jul 8, 2011 | 05:00 PM
  #1  
BRD-PREY's Avatar
Thread Starter
TECH Regular
iTrader: (5)
 
Joined: Oct 2008
Posts: 467
Likes: 1
From: Lakeland, FL
Default Indexing a Scattershield

Well, I have had a Quick Time Scattershield for some time now and I just rebuilt my T-56 (different thread) and installed a new RAM 9.5 Aluminum flywheel dual disk. Rated at 800ft lbs and only around $950.00 a great deal this is an awesome clutch, even now right out of the box it was a nice pedal feel not on/off.
Anyway back to the story:
So, the instructions talked about indexing aftermarket bellhousings. I never did that before and it was a new idea concept to me. So, I searched here and there and most people are like oh, you can't get the offset pins for a LS motor or you don't need to do it with Quick Times scattershield etc etc. Well, let me tell you BULLSHIT!
I stuck a dial indicator on the shield and it was so bad I couldn't tell which way to move it.

Luckily my tranny was apart so I mounted the tranny front plate to the scattershield and indexed off the input bearing race support.
Now the readings made sense.


Well, I was able to determine that I was like .022 off center. Thats an awful lot more than the .005 the spec calls for, so I ordered offset extra long pins. They only come in .007 increments so I need .014 as you need half of your total runout.

They came in and what a nightmare it is to find exactly where they need to go, it seems straight forward but I spend half the day spinning them around and remeasuring. It all finally came out and I was able to get just to the allowable spec. .010 total or .005 +/-





Look carefully at the final numbers on the scattershield, thats why I couldn't index off it is egg-shaped.


final note: I will always index my bellhousings/scattershields The amount it was off surely would have ruined something, clutch tranny etc.
ed
Reply
Old Jul 8, 2011 | 06:13 PM
  #2  
Zmg00camaross's Avatar
10 Second Club
15 Year Member
Photogenic
Photoriffic
Liked
iTrader: (12)
 
Joined: Jun 2009
Posts: 5,069
Likes: 52
From: Missouri
Default

Hmm this is interesting. I didnt measure a damn thing if my quicktime bellhousing lol.
Reply
Old Jul 8, 2011 | 07:14 PM
  #3  
Dave-1970's Avatar
Staging Lane
 
Joined: Apr 2009
Posts: 65
Likes: 0
Default

Yeah, I had to index my Quicktime Bell. The bell was sending my tranny into the pilot bearing so crooked that the input shaft was rubbing the inner bore of the slave cylinder. Solution was to install some moroso adjustable .007'' offset dowel pins to get me to .002'' misalignment. Total pain because I had to R&I trans a few times, and running the engine with a crooked input shaft for a few minutes bent my brand new disc, but protection is worth it i guess. Always measure to be safe...
Reply
Old Jul 8, 2011 | 08:51 PM
  #4  
MetallicaMatt's Avatar
TECH Junkie
iTrader: (19)
 
Joined: Feb 2005
Posts: 3,155
Likes: 0
From: Sandusky, Ohio
Default

Sorry for the question, but when and why is this required? What causes the warping?
Reply
Old Jul 9, 2011 | 01:02 AM
  #5  
jmd's Avatar
jmd
TECH Addict
20 Year Member
Photogenic
Liked
Loved
iTrader: (4)
 
Joined: May 2002
Posts: 2,620
Likes: 36
From: T56th Street, Aridzona
Default

Originally Posted by MetallicaMatt
Sorry for the question, but when and why is this required? What causes the warping?
The input shaft should ideally index dead centre of the crankshaft when all parts are bolted up.

When installing an aftermarket scattershield, measuring is what needs done to assure the amount of runout (distance the input mis-matches crank center) is not excessive.

In the above well documented example, he installed offset pins in the block to re-align the QT so the runout was within spec.

Tedious, but necessary and straightforward work.
Reply
Old Jul 9, 2011 | 09:16 AM
  #6  
SWeiser31's Avatar
TECH Apprentice
iTrader: (9)
 
Joined: Jul 2007
Posts: 340
Likes: 0
From: Missouri
Default

Where did you get the offset pins? I got a pair from Moroso but didn't end up using them. Couldn't really find anyone else selling any at the time.
Reply
Old Jul 9, 2011 | 03:38 PM
  #7  
BRD-PREY's Avatar
Thread Starter
TECH Regular
iTrader: (5)
 
Joined: Oct 2008
Posts: 467
Likes: 1
From: Lakeland, FL
Default

summit racing
Reply
Old Jul 9, 2011 | 10:11 PM
  #8  
4WOFURY's Avatar
TECH Regular
iTrader: (2)
 
Joined: Jul 2008
Posts: 440
Likes: 0
From: Mobile, AL
Default

uh-oh.. didn't know about this when I installed my QT bellhousing..
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 Jul 10, 2011 | 10:48 AM
  #9  
BRD-PREY's Avatar
Thread Starter
TECH Regular
iTrader: (5)
 
Joined: Oct 2008
Posts: 467
Likes: 1
From: Lakeland, FL
Default Me neither

If it wasn't for the outstanding instructions that came with my RAM 9.5 inch twin I never would have know either.

Ed

PS that clutch is sooo streetable I love it.
Reply
Old Jul 10, 2011 | 04:08 PM
  #10  
25thhawk's Avatar
TECH Resident
iTrader: (3)
 
Joined: Jul 2003
Posts: 813
Likes: 1
Default

what were you measuring? from what to what? How could you do this if your trans wasn't apart? I put mine in and had no issues, but never measured either. But trans slid in perfect, sguare to bellhousing with no problems. But I need to pull trans back out again this winter, so I would like to measure it then. Thanks

Ryan
Reply
Old Jul 10, 2011 | 04:40 PM
  #11  
BRD-PREY's Avatar
Thread Starter
TECH Regular
iTrader: (5)
 
Joined: Oct 2008
Posts: 467
Likes: 1
From: Lakeland, FL
Default

Normally you only measure the bellhousing only. I had to measure the transmission front plate because the scattershield opening was egg shaped. Hopefully you won't.
You put a dial indicator on your crank flange or flywheel. I made a bolt on bracket because I already had the flywheel bolted on and it was aluminum and the dial indicator magnetic base won't stick. So anyway you mount the dial indicator to you crank and have it read off the bellhousing opening. You then rotate the crank and measure the total runout. You divide that half and the is the pin offset you need. You only need to worry if its over +/- .005.
You then need to install the pin so the opening is in the middle, ie equal runout on both side.
Ed
Reply
Old Jul 10, 2011 | 07:35 PM
  #12  
25thhawk's Avatar
TECH Resident
iTrader: (3)
 
Joined: Jul 2003
Posts: 813
Likes: 1
Default

If you do this without the front plate of the trans, arent you only guaranteeing that the opening of the bellhousing is right? There is no way to tell if the opening is cut right or holes drilled in the correct place, right? It seems like there would be a better way to do it. So I would need to remove my clutch to measure for this? Thanks

Ryan
Reply
Old Jul 10, 2011 | 08:18 PM
  #13  
BRD-PREY's Avatar
Thread Starter
TECH Regular
iTrader: (5)
 
Joined: Oct 2008
Posts: 467
Likes: 1
From: Lakeland, FL
Default

Yes, your absolutely correct. You would only be measuring the bellhousing/scattershield cut opening. That is what is normally done. I only went farther because the bellhousing was egg shaped and I couldn't make heads or tails of what I had. Yes, clutch off flywheel either on or off.
Ed
Reply
Old Mar 17, 2015 | 05:15 PM
  #14  
johnw999's Avatar
Teching In
10 Year Member
 
Joined: Jan 2013
Posts: 16
Likes: 0
Default

Ok - I measured the bellhousing alignment. I used a JEGS dial indicator. Most dial indicators go to 100. This one goes to 50. I measure 16 on the indicator. Does that mean the alignment is off by .016 inches? Also, which dowel pins do I buy?


Reply
Old Mar 17, 2015 | 06:59 PM
  #15  
SWeiser31's Avatar
TECH Apprentice
iTrader: (9)
 
Joined: Jul 2007
Posts: 340
Likes: 0
From: Missouri
Default

Yeah that should be .016. I found these dowel pins from a youtube video on indexing a bellhousing. http://www.robbmcperformance.com/products/dowels.html

I've never used them, but they look nice! Much easier than drilling the block.
Reply
Old Mar 18, 2015 | 08:13 AM
  #16  
johnw999's Avatar
Teching In
10 Year Member
 
Joined: Jan 2013
Posts: 16
Likes: 0
Default

Thanks - I see it now. On the gauge, it shows that each mark equals .0005 inches. There are 31 marks until 16 on the guage.
31x.0005=.0155 inches

.007 offset dowel pins are in my future
Reply
Old Sep 9, 2015 | 08:29 AM
  #17  
johnw999's Avatar
Teching In
10 Year Member
 
Joined: Jan 2013
Posts: 16
Likes: 0
Default

I think I finally have the quicktime bellhousing aligned within the .005 specs. For the longest time, I couldn't get the bellhousing to move to the right with the offset dowel pins. Then I noticed that the right bolt touches the bellhousing. I removed that bolt, and measure again. That made the difference, but I'm surprised that was the problem. Has anyone else experienced this?

Reply




All times are GMT -5. The time now is 11:52 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