Flywheel indexing?
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Joined: Oct 2003
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From: Storm lake Iowa
Flywheel indexing?
I recently installed a TKO 5-speed, along with a new (carbon fiber) driveshaft. Love it! I did notice a vibration at 80-90 mph that wasn't there before though, which settles down over 100 mph (don't ask me how I know this 
).
I had the flywheel resurfaced before installing the new clutch and pressure plate, but it occurs to me that I don't remember if there was an indexing mark on the flywheel or crank...is this idiot proof (i hope?), or could I have reinstalled my flywheel in a different orientation to the crank (i.e., rotated to have holes 60, 120, or 180 degrees off)? This engine is a mongrel with somewhat obscure pedigree, I haven't had it completely apart yet, and I don't know if it is internally or externally balanced...since it drives fine except that transient high rpm vibration, I'm guessing I can get away with it until this winter when I pull and rebuild or replace, but I'm going crazy wondering if I have the flywheel misaligned. Can anyone reassure me?
-Roy
).I had the flywheel resurfaced before installing the new clutch and pressure plate, but it occurs to me that I don't remember if there was an indexing mark on the flywheel or crank...is this idiot proof (i hope?), or could I have reinstalled my flywheel in a different orientation to the crank (i.e., rotated to have holes 60, 120, or 180 degrees off)? This engine is a mongrel with somewhat obscure pedigree, I haven't had it completely apart yet, and I don't know if it is internally or externally balanced...since it drives fine except that transient high rpm vibration, I'm guessing I can get away with it until this winter when I pull and rebuild or replace, but I'm going crazy wondering if I have the flywheel misaligned. Can anyone reassure me?
-Roy
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Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
If you recently installed the tremec and now it vibrates it is possible on the installion that you didn't align everything right. When you installed the tremec you have to make a rear mount. If you push the rear of the transmission as high as possible, until the transmission is almost touching the tunnel, also cut clearance for the tower you get close to stock alignment. You also need to measure the down angle of the output shaft and then make the pinion angle match this but up not down.
You want equal and opposite angles. Transmission is always down so make the rearend up. This is done my cutting the rubber/poly donut.
You want equal and opposite angles. Transmission is always down so make the rearend up. This is done my cutting the rubber/poly donut.
Last edited by norvalwilhelm; May 11, 2005 at 02:36 PM.
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Joined: Oct 2003
Posts: 641
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From: Storm lake Iowa
Originally Posted by norvalwilhelm
You can't put it on wrong. It is idiot proof. If all the bolts are in you have it right.
If you recently installed the tremec and now it vibrates it is possible on the installion that you didn't align everything right. When you installed the tremec you have to make a rear mount. If you push the rear of the transmission as high as possible, until the transmission is almost touching the tunnel, also cut clearance for the tower you get close to stock alignment. You also need to measure the down angle of the output shaft and then make the pinion angle match this but up not down.
You want equal and opposite angles. Transmission is always down so make the rearend up. This is done my cutting the rubber/poly donut.
If you recently installed the tremec and now it vibrates it is possible on the installion that you didn't align everything right. When you installed the tremec you have to make a rear mount. If you push the rear of the transmission as high as possible, until the transmission is almost touching the tunnel, also cut clearance for the tower you get close to stock alignment. You also need to measure the down angle of the output shaft and then make the pinion angle match this but up not down.
You want equal and opposite angles. Transmission is always down so make the rearend up. This is done my cutting the rubber/poly donut.
I did raise the tail of the transmission as high as I could manage, the top of the housing around the shifter sits about 1/8" above the interior surface of the trans tunnel. I have not yet tried to measure the transmission angle, nor compare to the rear pinion angle, but after reading this recently posted link on driveline angle theory,
http://www.vibratesoftware.com/html_...ols%20Required
I've put it on my to-do list.
Funny thing is, it's only at a particular speed/rpm, which fits with it developing a harmonic resonance. In theory it could also be the pressure plate or driveshaft, since both are new to the driveline.
How do you measure your angles Norval?
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
I used a magnetic protrator. It is compact and really reads small angles.
I had a vibration at 62, stayed untill 70 where it went away and came back agian at 90 with a vengence.
I aligned the drivetrain and it went away.
Dead calm to 130 with no rattle in the shift handle.
I had a vibration at 62, stayed untill 70 where it went away and came back agian at 90 with a vengence.
I aligned the drivetrain and it went away.
Dead calm to 130 with no rattle in the shift handle.
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