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Fork and throwout bearing for SBF with 1-3/8 input?

arse_sidewards

Contrary to everything
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May 19, 2020
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I got a trans that I'm trying to put behind an SBF (well, a 300 but it uses the same bell so let's call it an SBF to make things easy on the simpletons). I want to run a hydraulic clutch with an external slave like you'd find in an 80s truck with a 4spd or 90s BBF with a 5spd. I have a bell housing from an 80s van. The bearing retainer OD on the trans is 5.125 but it's trivially easy to open up the bell on the lathe.

The trans input is 1-3/8 x 10spl. I'm going to use a stock pressure plate for an 11" clutch and an 11" clutch disk that uses a 1-3/8 input and trim the fingers of the clutch disk if needed to clear the bearing retainer.

I have no idea WTF I need for the clutch fork and throw-out bearing. Does a 60s 427 use the same pivot distance and pivot ball size? If so then I can probably just use an off the shelf throw-out and fork from that fuck around with slave cylinders until I find something that's right ratio. Part of me says just get whatever throw-out bearing looks easy to make a fork for and then just roll with that.

The applications that have 1-3/8 trans inputs that come to mind are 60s 427, 40s/50s flathead v8 and Dodge/GM with the NV4500 and some Chevys with the SM465. I'm hoping to be able to cobble together off the shelf parts to make this work. Ideally the only thing I want to make myself is the clutch slave cylinder bracket but I'll make or modify a fork too if I need to.

Anyone have any bright ideas?
 
Pretty sure FE' used a throwout bushing. What transmission are you running? Why not use the bearing and fork for that transmission?
 
FE uses a bearing. Transmission is a Clark 5spd

Ram 486 is the part number for the throw out bearing. The fork is a weird half circle looking thing that rides in the clamps. You could take one and adapt it to fit your slave cylinder.

As far as a throw out bearing from a factory hydraulic clutch that will fit I'm not sure. I could check a few parts catalogs tomorrow.
 
Ram 486 is the part number for the throw out bearing. The fork is a weird half circle looking thing that rides in the clamps. You could take one and adapt it to fit your slave cylinder.

As far as a throw out bearing from a factory hydraulic clutch that will fit I'm not sure. I could check a few parts catalogs tomorrow.


If/when you look through catalogs it would be great if you could give me a couple sample applications for the Ram 486. Since I'm so far away from getting the trans installed in anything I'd prefer to buy an NOS or new Chinese bearing by application for a fraction of the price.
 
Looks like part number N1493 is what I'm after. Example application is a 1970 Torino with the 429.

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The input shaft is 1.375". The bearing retainer OD is 1.74". At least on the big input Ford transmissions, don't know about the Clark.

I haven't measured the Clark in awhile but I recall it being the same. I own a welder and a lathe so it's not like it matters either way.
 
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