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Hi all
Which would be the stronger gearbox case
Top or bottom for when I fit an OS Giken gear kit?
thinking of the gearbox case flexing under high power?
thanks Mark
Multi-rib box looks like something out of a commercial vehicle. Other one, unless it's been hydroblasted, based on less as-cast appearance, looks to be an earlier 5 speed, rather than FD.
All other thing being equal - wall thickness and so forth - you'd think the second one would be stronger...probably still find 3rd is a worry in a box with it's genesis 50 years ago.
Not sure what the second box is from but I do know the tailshaft is shorter. I thought the same about the strength so tempted to use the case.
the top box is a FD box out of a 1994 car.
ate there another FD cases that are stronger?
thanks
The shaft, bearing and gear tooth profile have a bigger impact on when it will fail. You can make the outside as thick as you want but with the same shafts and bearings 3rd gear will still push itself apart/throw teeth eventually.
If you were trying to limit torsion a steel base plate would probably make more difference than anything else.
Not sure what the second box is from but I do know the tailshaft is shorter. I thought the same about the strength so tempted to use the case.
the top box is a FD box out of a 1994 car.
ate there another FD cases that are stronger?
thanks
Haven't checked for a part number change, all the cases are identical afaik, minor changes internally, one switch location plugged with a bolt are about the sum total.
Could be on drugs, I think I've seen the rear sandwich plate as well as the sump plate made in 6061 some time in the past, have doubts there would be much improvement really. That second box is probably out of a Bravo or the Ford equivalent....interesting to see if beefier inside.......input and output shaft differences with the changed bellhousing and extension housing might stop a straight swap.
