Help centering bellhousing
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,501
Likes: 323
From: San Diego
Help centering bellhousing
I have watched all the youtube videos and they make it look easy but it has taken me forever just to get to where I can do a full sweep and then return to zero. Now my numbers seem so far off that it doesnt seem like this bellhousing can be centered. Am I doing something wrong?
I get:
3 o’clock = 0
6 o’clock = +.17
9 o’clock = -.95
12 o’clock = +1.23
All the videos show most bellhousing out by like .007 but this one seems way out. I checked it for level and it seems to be
I get:
3 o’clock = 0
6 o’clock = +.17
9 o’clock = -.95
12 o’clock = +1.23
All the videos show most bellhousing out by like .007 but this one seems way out. I checked it for level and it seems to be
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,501
Likes: 323
From: San Diego
So I took a break and tried again. This time I had my son rotate the engine while I recorded numbers.
We went around twice and it returned to zero each time. Then we got these numbers:
6 o’clock = 0
3 o’clock = -.22
12 o’clock = -.57
9 o’clock = -.25
Any recommendations?
We went around twice and it returned to zero each time. Then we got these numbers:
6 o’clock = 0
3 o’clock = -.22
12 o’clock = -.57
9 o’clock = -.25
Any recommendations?
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,501
Likes: 323
From: San Diego
So just to clarify, I am under the impression that the most offset that is made is a .021. If I move it up .021 then I think I am outside the .005 allowed for a Tremec transmission. What do I do?
Drifting
Joined: Dec 2011
Posts: 1,743
Likes: 289
From: Chardon Ohio
I would make the correction to the offset and measure again and see where you are. But yeah, I think .005 is too much.
Here is a thread I did on dialing in the bell housing if it helps: Super T10 -> TKO 600 install - CorvetteForum - Chevrolet Corvette Forum Discussion
Jim
Here is a thread I did on dialing in the bell housing if it helps: Super T10 -> TKO 600 install - CorvetteForum - Chevrolet Corvette Forum Discussion
Jim
Drifting
Joined: Dec 2011
Posts: 1,743
Likes: 289
From: Chardon Ohio
Anything is possible but I would get it as good as you can with your offset dowel pins and see where you are and go from there.
You could check the BH bore at various places with calipers and see if there is big variation.
You could check the BH bore at various places with calipers and see if there is big variation.
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Verdad Gallardo
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,501
From: Little Rock AR
Basically, you reset the indicator to read zero at the point where the indicator reverses direction (clockwise to counterclockwise)Then the opposite direction will read the runout. You purchase offset dowell pins that are half the high reading on the indicator.
Example: I had a low reading (reversing direction) at about 5:00. I set my indicator to read zero at about 5:00 or so. 180 degrees away at about 11:00 it was reading .016" so my correction needed was half of that = .008". I bought a pair of offset dowells at .007" (which was as close as I could buy). Installed them to move the bellhousing. 007" in the direction the bellhousing was off and it actually came in close to perfect zero on recheck.
Example: I had a low reading (reversing direction) at about 5:00. I set my indicator to read zero at about 5:00 or so. 180 degrees away at about 11:00 it was reading .016" so my correction needed was half of that = .008". I bought a pair of offset dowells at .007" (which was as close as I could buy). Installed them to move the bellhousing. 007" in the direction the bellhousing was off and it actually came in close to perfect zero on recheck.
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,501
Likes: 323
From: San Diego
So I finally got it dialed in to about .004” so its within spec. It definitely made the trans mounting very easy. Didnt even have to really fight with it.
But a few things I found:
1. the recommendation to torque the bellhousing helped alot
2. I ordered the Moroso offset dowel pins. They dont show a front or a back and after alot of research, I had them in backwards.
3. To remove the dowel pins, an air hammer on the back works excellent and pushes them right out
4. I had a digital dial indicator and forgot to switch it to inches and had it on mm. Thats why my numbers were so large and seemed so far off. 🤦🏻♂️
But a few things I found:
1. the recommendation to torque the bellhousing helped alot
2. I ordered the Moroso offset dowel pins. They dont show a front or a back and after alot of research, I had them in backwards.
3. To remove the dowel pins, an air hammer on the back works excellent and pushes them right out
4. I had a digital dial indicator and forgot to switch it to inches and had it on mm. Thats why my numbers were so large and seemed so far off. 🤦🏻♂️
