Pilot bushing for 4 speed swap

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The early SB cranks were ALL drilled for pilot bushings. Some actually got the bushings installed even though it was an automatic application.
You need nothing but a simple, stock pilot bushing to make yours work.
Dont drill anything, dont cut anything..just tap the bushing in.
 
cosgig said:
You have options, and none of those options require you to disassemble anything! First, simply check the rear register of the crank for the pilot bushing, you may get lucky and there will be one already installed! If there is not one, you can have the outside diameter of a new bushing turned down to the pilot hole size by any competent machine shop, and just tap it into the unreamed hole, which is what I've done more than a few times with no problems! You can also buy the pilot bearing that fits into the crank register where the snout of your automatics torque converter about would usually ride!! Then just assemble as usual and you will be all set! You're gonna need the pedals too, as I'm sure you know, and I hope you grabbed the frame mounting bracket for the Z bar!
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Update: got the motor cleaned off and decided I should mock the trans up now before I start doing some head work and getting a cam. I put the bellhousing on and put the trans and it fit with ease. So sounds like I don't need to cut the input shaft or drill the crank deeper? I still haven't gotten the bushing, would that affect it? In regards to if I will need to modify the crank or input shaft? Thanks!

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I've yet to see a smallblock that needed to have the input shaft cutoff. Grab that adapter bearing and be done.
 
Well, if you are lucky, it's drilled for a bushing. That solves that. The two or three I've messed with that had 4 speeds weren't. Bearing pilots are better in my opinion anyway. Perhaps you have a crank ready for bushing. I've never been that lucky.
 
Mopar92 said:
Well, if you are lucky, it's drilled for a bushing. That solves that. The two or three I've messed with that had 4 speeds weren't. Bearing pilots are better in my opinion anyway. Perhaps you have a crank ready for bushing. I've never been that lucky.
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Ok. I've just heard that they can eat your input shaft if not properly aligned. I ordered a bushing from my auto parts store so I'll go pick that up tomorow
 
68cuder said:
I've just heard that they can eat your input shaft if not properly aligned.
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I have seen only one undercut input shaft due to the bearing picture posted on either this forum or B-Bodies. Alignment and or bearing failure probably.
So will you indicate the bell in anyway?
Myself, I favor the bushing. To me it's the way to go. But that said, I've also seen several bushings come out seized to the input shafts, IMO, likely due to improper fit.
 
68cuder said:
I'm hesitant on using the bearing. Id rather use a bushing.
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Nothing wrong at all with the bearing, IF your block to scattershield/bell alignment is perfect. If it's out by more than about 7 thou, it will eat it up in a summer. Even quicker if you throw in 20 or 30 passes.
 
Ironmike said:
Nothing wrong at all with the bearing, IF your block to scattershield/bell alignment is perfect. If it's out by more than about 7 thou, it will eat it up in a summer. Even quicker if you throw in 20 or 30 passes.
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How do I check for perfect alignment?
 
68cuder said:
How do I check for perfect alignment?
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Mag base dial indicator stand on the crank and rotate slowly. Indicator tip riding on inside of bellhousing. I'm sure there's something on you tube that could show you.
My Quicktime was out 14 thou on the first motor. Only 7 on the prior. You might need offset dowel pins for the bell.
 
Ironmike said:
Hey Dave, what does ma Mopar say is the acceptable run out?
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.008" max per the book. My Lakewood was out .010". But I was lazy and had a bushing(shame on me).
IMO, if you use the bearing the closer you can get to zero the better.

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68cuder said:
i cant imagine a stock sb bellhousing could possibly be out of alignment
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In the perfect world everything fits and works. Unfortunately someone added tolerances to things using statistical process control measures so they could actually ship product at a profit. And it became good enough. Consider two items assembled together, each at the opposite of ends of their control limits. It may bolt and work but may not be ideal for the assembly.
IMO, It's likely close enough to make the spec. Many have just bolted things together and have been just fine. And BTW, some of those pins can be a PITA to remove too.
But, you don't know if you don't check it. If you have the opportunity to check it, why not check it. At the very least you would know one way or the other. You may just head off a potential issue. I still believe if you use the bearing the closer you can get to zero the better.
 
68cuder said:
the reason I ask is because brewers sells offset pins but they specifically say WILL NOT FIT SMALL BLOCK BELLHOUSINGS. Sorry if this is a stupid question, i am just new to this
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Didn't mean to come off that way, man. No at all. Anyhow Mopar tolerances everywhere can be all over the board......I did a clutch for a friend's factory unmolested Charger and that bell to block was so bad we hade to fab up some pins that would give us around..030 offset. No wonder he had so much tranny work over the years.

Summit has several different brands of offset dowels and I think they all work in factory housings. Don't know why Brewers would say that.

Well now that you know, you can check it, correct it if needed, and feel damn good about it. Good luck!
 
Got my clutch kit in today and it came with two bushings. I've only ever seen the shorter bronze bushing used, what's the taller one for? Also looks like it will fit! Used a mic and both are at like 26mm I forgot the exact measurement.

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whitepunkonnitro said:
The early SB cranks were ALL drilled for pilot bushings. Some actually got the bushings installed even though it was an automatic application.
You need nothing but a simple, stock pilot bushing to make yours work.
Dont drill anything, dont cut anything..just tap the bushing in.
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When you say early SB cranks, what do you mean ?
Year, displacement ?
I'm gonna be dealing with this issue too.

Thanx
 
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