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Discussion Starter · #1 ·
Hi guys, I have a McLoud bell housing and a new Tremec TKO. They talk about dialing in the bell housing to .005 runout. Since I have never dialed in a bell housing before, what steps do I need to do? Thanks for your help.

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This is off the McLeod website:

Bellhousings BACK to TOP
In order for a clutch, transmission and related parts to function properly the bellhousing must have two surfaces parallel to each other. One is where the bellhousing bolts to the motor. Where the transmission bolts to the bellhousing is the other. To check this, use a dial indicator with a magnetic base. Attach the base to crankshaft and indicator to (top) or transmission mating surface. Turn flywheel and mark the surface with something you can read (chalk, magic marker, etc.). Maximum runout is + 0.005 to -0.005.
To correct out of parallel; take bellhousing to someone that does Blanchard grinding (most steel flame cutter people have one). Place the engine surface down on the table and have them grind the transmission mating surface to bring it into parallel.
Center Hole or Bore Out of Alignment:
If center bore doesn't run true to the center of the crank or pilot bushing, the clutch disc will suffer and possibly effect the transmission front bearing too. Irratic clutch engagement and disengagement can occur. Sometimes in the center of the disc will break completely out if this problem is not corrected.
To check alignment in the car McLeod has a dial indicator tool that attaches to the crank with a magnet or use a regular magnet base indicator holder. Once the base is secure, set indicator dial at "O". Slowly move the flywheel and observe the indicator. The maximum McLeod recommends for the housing to be out alignment is +0.008 to -0.008. When watching indicator it is best to mark the center bore in four places then read and record the indicator reading at those four positions. (We recommend the four positions be like a plus sign in math:) Example +.
Correction of bellhousing alignment is usually done with off-set dowel pins. Check with your local speed shop for appropriate part# and off-set. If your bellhousing is not a McLeod and it runs our of alignment more than 0.040 out on the block, then we recommend purchasing a new McLeod Housing.

Basically the dial indicator reads off the inside of the bellhousing bore (the round area that locates the front of the trans).

There are better instructions and pics on the Lakewood site, but it's in Adobe Acrobat and won't let me copy and paste it.

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