Indeed we had problems with the transmission/bellhousing cracking, but,
remember we were using the engine and CAR at the highest amount of
usage, I.E. high revs for at least thirty to forty-five minute races.
This is 6500 revs for a good long time.As you have surmised there is a
method of aiding the situation,the mounts, and indeed this does help.
We did make mounts that supported the junction of the engine to the
transmission. We used small rubber engine mounts with long strap iron
brackets that came down to the bell housing bolts and the mounts were on
each side of the battery box. This did make a positive difference. But,
we never had this problem until we started making real power, that is
above 150 BHP. We broke at least ten or fifteen of the gearbox housings
until we made the hangers with rubber mounts . We still cracked the
casings , but the whole business at least held togeather for the length
of the event. At one time I also welded side plates onto the the gearbox
case but they also cracked. This was probably because they were very
soft after being annealed by the welding. I think I might have worried a
lot of people without cause for most will probably NEVER use the cars
and engines as hard as we did at that time. I'll try to answer any
comments on this.
DLMAssoc@aol.com wrote:
> FOTers:
>
> The discussion of bell housing breakage in early TR4s is very timely for me...
> I'm ready to put one in a car but have stopped till I figure out what to do to
> minimize the possibility of cracking.
>
> Kas has explained about the "gong" device they used to use, and Nick (at least
> I think it was Nick) has recommended welding braces from the bell housing to
> the tranny. Another "old" TR racer I talked to today said the problem was
> probably caused by the combination of engine and tranny flexing, since they
> were supported only by the front motor mounts and the tranny mount at the
> rear. Without support in the middle, the flexing would break the bell
> housing. He said he used to install motor mounts at the rear of the engine to
> eliminate the flex. This seems to make sense, but I wonder if anyone else has
> done this or is there some reason this wouldn't take care of it.
>
> Thanks...
> Don Marshall
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