Thanks Jon,
Still kicking ideas around. The problem/requirement is coming up with a solution that accounts for the drivers inbd and outbd relative to the case. I want to tie it into the diff cover as this makes a fantastic shear panel to build off of.

Started some layout work.
Using the existing file as the baseline.
I'd add pictures but the website is not cooperating?

This came up in Facebook a week or so ago. I saved the picture for you but never got around to uploading it.

What transmissions had these two bosses on them?

Generally, it was very early transmissions that used those bosses. They were part of the motor mount for the pre-B20 motors.
I've seen it carry through for many years after...

John

Chouan wrote:This came up in Facebook a week or so ago. I saved the picture for you but never got around to uploading it.

Thanks Chouan. I'd say not the most elegant solution, but a solution nonetheless. I like how it ties into the side cover, but not the giant billet block of aluminum.

A photo I found on the internet long ago

Something that Brad Schaffner had done.

Dennis,
Is the basic reinforcement to limit overall flex of the transmission case ?
If so would a tie thru the case from side to side be an option ?
Thinking about being able to tie a plate on each side thru the case itself with a stud or bolt
all the way thru ? - and /or tie across under the case ? - or up to the top of the case where the bottom
of the block is stronger ?
Are there examples of failure or is it the flex before failure that allows gear mesh to be altered that is the goal ?
I recall Jak Stoll explaining to me how enough torque at a particular rpm would 'unmesh' the gears until
they would strip the teeth off each other.

The reinforcement is to help prevent the differential from exiting the passenger side of the transmission. With a high load the forces of the ring and pinion push on the passenger side of the case and can blow that side completely apart....in High power applications.

Thanks for the photo trolling. Can't see the Schaffer cap doing much, if anything. The side plate tie in is pretty sweet. I worry about preloading the driver and dorking with the Ring and Pinion backlash. If it is a one off maybe to so much. If it is a 99/ c900 universal fit, need to take in account fitup variance.
I have been thinking about doing the left side for some sympathetic loading, but the real issue is the right as the resultant force from the pinion and ring is a load on the case to the right. Once the case is stress and the gears pull apart, no good will become of it.
Next question. How many of you would buy this strap on? Ball park estimate 350-400$ I ask to drive the design. If it is just me that needs it, I'll just weld the assembly to fit my specific application?

My anecdotal evidence is that I've never seen a failure in this area simply from just having a lot of power.

squaab99t wrote:I worry about preloading the driver and dorking with the Ring and Pinion backlash. If it is a one off maybe to so much. If it is a 99/ c900 universal fit, need to take in account fitup variance.

Dennis, if you have the right side axle bearing housing shimmed, at say .040", and the max that you have ever seen in that position was 0.60", just add another 0.020" shim between the outside of the bearing housing and the girdle. Designing like this would still allow you to set the shim height, to what ever is needed, and then add the rest of the shims, up to a total of the 0.060" between the outside of the housing and the girdle.

Jordan wrote:My anecdotal evidence is that I've never seen a failure in this area simply from just having a lot of power.

Jordan, do you think the failures in this area are attributed to gearboxes that were already severely worn and then taken over the edge with additional power?

I have never seen this area fail. I recall seeing a picture at some point in time but have never been able to find it again....of a blown apart diff housing. Other than the neato factor I have no need for one. I can understand the need to protect your investment in a pricey gearbox build though.