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Discussion Starter · #1 ·
67 Camaro, new BPE 383 (one piece rear main), new Lakewood bellhousing, Richmond Super T10 transmission.

When I removed the transmission from the old motor, I inspected the input shaft for wear/slop. Looking at the pilot shaft and the marks left behind from the pilot bushing, it appeared that there was at least .500" of space where the pilot shaft wasn't contacting anything. While buying parts to put everything back together, I picked up an extra long pilot bushing to see if it would fit and give me more bushing/shaft contact. I know they're typically used when torque plates or engine mounts are added between the bellhousing and block, but if it fits my application, more contact between the shaft and bushing has to be better, right? The long bushing measures 1.012". If it doesn't work, I'll pull it and put a standard bushing in it.

I took a bunch of measurements last night and everything measured okay, so I decided to do a test fit before installing the clutch. I drove the bushing in until it hit bottom, bolted the bellhousing to the trans, and slid the trans/bellhousing on to the block. The bellhousing slid right up tight to the block, so I bolted it on. I reached in through the shift fork opening and can spin the input shaft with a thumb/index finger, so everything moves freely. I took some photos with my cell phone and ran a bore scope in to verify clearance.

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I asked two knowledgeable buddies what they thought about it and one (former dirt track car builder) said should be good to go, and the other (old school drag racer) asked me how much clearance there was between the bushing and spline shaft. The latter got me second guessing myself.

I'm planning on mashing some putty in there to get a ballpark indication of clearance unless you knowledgeable folks can offer other guidance. Everything I've searched for talks about ID & OD dimensions but nothing really about gap between bushing and spline shaft. Thoughts?
 

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Is the Lakewood bellhousing the same depth as the part it's replacing? Was the wear pattern on the input shaft the full depth of the pilot bushing? Is yes to both, I'd use a pilot bushing that matched the old part. I think you're trying to address a problem that doesn't exist.
 

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Discussion Starter · #3 ·
The Lakewood bellhousing is a 621 replacement. I haven't measured it against the original GM housing but can do so easily enough. I'll also look at the old bushing to see if the wear is full depth or partial.

I agree that there's probably not a problem with the original setup, just trying to make an improvement if I can...more support for the shaft.
 

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I would be careful. If things expand it could push the crank forward which would kill the thrust bearing.
 
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I drove the bushing in until it hit bottom,
Thoughts?
That bushing may be a real bear to get out if you ever have to replace it and it is bottomed out against the crank.
 

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If I remember correctly I believe Lakewood recommends using the standard pilot bushing. If it was mine I'd follow their directions and not take a chance.
 

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That bushing may be a real bear to get out if you ever have to replace it and it is bottomed out against the crank.
The bread method seems to get them out. I had one in my 396 crank and I tried 2 different pullers to get it out with no luck. I stuffed the hole with bread and used a bolt about the size of the hole in the pilot bearing. Tapped on the bolt with a hammer and the bearing came right out. Plus the bread is so much cleaner than using grease.
 

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Discussion Starter · #8 ·
Alright, thanks fellas. I have a standard bushing I'll put in there instead. I was just spit-balling a potential improvement.

FWIW, the old bushing had no wear mark so it appears that the pilot shaft was all the way into the bushing.
 

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You could machine down the length of this extended length pilot bushing if you felt it was too long possibly contacting spline part of input shaft if you feel a longer pilot is needed

IMHO you don't want to "bottom out" a pilot bushing/bearing against crank. pilot bushings were intended to be removed with a blind hole puller so a "gap" (min. about 1/8") between the bottom of bushing and crank recess is needed

I find this blind hole puller is plug & play in removing pilot bearings. Autozone #27128 has it as a loan-a-tool or Harbor Freight has it to buy also


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Discussion Starter · #10 ·
There is a lip inside the crank that keeps the bushing from bottoming out. There is also a lip around the outer portion of the bushing that keeps it from going in any further than a standard bushing would (the extended portion is larger OD than the rest of it). I'm certain the bread trick will work but if not, there is an opening back there that a puller would grab.

I actually thought about machining the extended portion down a bit to offer more clearance but I don't know how much to take off...no idea how much expansion occurs.
 

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There is a lip inside the crank that keeps the bushing from bottoming out. There is also a lip around the outer portion of the bushing that keeps it from going in any further than a standard bushing would (the extended portion is larger OD than the rest of it). I'm certain the bread trick will work but if not, there is an opening back there that a puller would grab.

I actually thought about machining the extended portion down a bit to offer more clearance but I don't know how much to take off...no idea how much expansion occurs.
When I was pulling the one on my 396 recently, I tried a slide hammer style puller and a traditional puller which both had the two fingers to grab the back of the bushing. With the slide hammer the bushing wouldn't move and with the traditional puller I would put enough pressure that the fingers would flex enough to slip off the back of the bushing.

Another thing I noticed is some of the "bronze" bushings evidently have steel in them and are magnetic. I've head they cause problems on the muncie trannys so I made sure the one I used was a true non magnetic sintered bronze bushing.
 

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Discussion Starter · #12 ·
It's on an engine stand so I have plenty of light and room to move about. If the bread thing doesn't work, I'll grab a puller. If the puller doesn't work, I'll drill/dremel it out. I saw a video where a guy threaded a bolt through it, bottomed the bolt on the crank, and the bushing just threaded out.
 

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Finding a good "sintered bronze" bushing wasn't that easy, eventually I found this one....
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Years ago I purchased a pilot bearing for my Muncie from Paul @ 5speeds.com

When I rebuilt my Muncie I used parts from Autogear who I believe is a major supplier to the industry.
 

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Your input shaft should penetrate into the pilot bushing (at a minimum) the same distance as the diameter of the input shaft. So if memory serves me correctly roughly 5/8 inch. By measuring from the aft face of the pilot bushing to the contact surface of the bell housing then comparing that measurement from the face of the transmission to the tip of the input shaft one can calculate how far the input shaft penetrates the pilot bearing. If it pentrates at least as far as the diameter of the input shaft there is no need for an extend pilot bushing.
 

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Discussion Starter · #18 ·
I removed the extended bushing and installed a standard one this weekend. Before removing it, I squeezed some Silly Putty in there. After removal of the trans, I measured the silly putty with a caliper and it was only .125". I measured from the rear face of the bellhousing to the bushing, and from the mounting face of the trans to the pilot shaft and it measured pretty close to the same dimensions. Too close for comfort.
 
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