Small Block Protective Gearbox Spacer

[Dirk_S]

Does anybody know if the inner diameter of the gearbox output for a V7 III matches with older small blocks? I’d like to add a steel spacer/bush to my gearbox output sooner than later to protect it in the event the UJ goes kaboom. I know some folks simply make them, but there have been a couple suppliers. MW Motoren, out of the Netherlands (the shop that focuses on the V50 NATO), sells one marketed for the V50, so I’m curious if the output diameter remained or changed over the years, especially once the 6-speed came around.

[Chuck in Indiana]

It's not even the same from early to late production.  I have no idea about the 6 speed.

[Dirk_S]

Thanks, Chuck. I see that both the driveshaft and boot date from the V7 III all the way back to 1982. Certainly not a definitive lead, but it’s mildly promising.

[huub]

they fitted to the smallblocks i had , they are not a press fit , you glue them in place ( i use silicon kit)
there are fit differences , on a V65 they fit tighter as for a V50 of the first series.
probably due to wear on the moulds in which the cast the gearbox cover

having said that, never owned V7III, so who knows.
Did you ask MW motoren?

[Dirk_S]

they fitted to the smallblocks i had , they are not a press fit , you glue them in place ( i use silicon kit)

Ah, I thought they were a press fit. RTV sealant or stronger?

Did you ask MW motoren?

I asked if they knew of any inner diameter differences between cases, to which they said they didn’t know. I should’ve asked instead the outer diameter of their steel bush.

I wanted to have a steel sleeve installed before I leave for a 2000+ mi trip in a few weeks on this V7 with these longer shocks, so I just decided to throw the dice and bought theirs last night. We’ll find out!

[Pescatore]

Hey Dirk, is this what you bought?
Would you report back on measurements and fit?
I would buy one for my V65.
Thanks,
P

[Dirk_S]

Hey Dirk, is this what you bought?
Would you report back on measurements and fit?
I would buy one for my V65.

That’s it, and can do!

[Dirk_S]

Received the steel gearbox sleeve in the mail today, just in the nick of time; I leave tomorrow morning for my trip. Probably won’t get the opportunity to install it today, but i’ll take it with me and try it out once I’m in PA at my family hub.



Sleeve is a cylinder that’s tapered on the outside, with a section of the circumference at the smaller end notched out a few mm from the end. Measurements follow as promised. Pics show the dirty caliper measurements, but listed here as well for ease of reference:

Inner diameter: ~58.47mm on both sides; pretty sure it’s just a straight bore.




Outer diameter, large tapered end: ~63.87mm




Outer diameter, small tapered end: ~60.82mm




Thickness, small tapered end:: ~1.15mm




Thickness, large tapered end: ~2.66mm



Distance between ends of notched area: ~50.86mm




Depth of notch from the smaller end: ~6mm

[Frenchfrog]

Good Dirk ! Hopefully it won't be needed but this is a very worthy  addition to any smallblock.

[Bob Wegman]

What is the purpose of this part?  I am in the dark on this subject?

[Antietam Classic Cycle]

What is the purpose of this part?  I am in the dark on this subject?

If the u-joint should happen to "grenade", the protective sleeve keeps it from busting the transmission cover.

[Bob Wegman]

Thank you Charlie

[Chuck in Indiana]

I doubt this will be useful on the new stuff, but old small block guru Rod Yeoman (RIP)  sent me this back in the day:
Hi Chuck,

The tubular bush is 58mm long. You need to cut about 60mm of arc to a depth of about 10mm from the front edge to fit around the casting protrusion.

Internal diameter is 58.5mm front to rear

Front external diameter is 61.15mm

Rear external diameter is 64.0mm

You may need to trim it down depending on your casting but that will be close. You may also get away with a slightly smaller internal diameter to thicken up the walls if you desire. I'm happy with what I have. The really thin front is well away from the uni but gives more surface to spread any possible impacts.

I used rubbery type goop for impact resistance as well rather than retaining fluid.

Cheers

Rod

[Pescatore]

Thanks Dirk, didn't know it's tapered.
Let us know how it fits.