Bill & Fred,
This is odd. I never heard of a diff. in length of the gearboxes from
TR3 to TR4.
It so happens I have my orig. TR4 non-OD gearbox (in need of rebuild,
mostly 1st gear synchro, drives like a 3 ;-) conveniently laying in my
garage alongside a freshly rebuilt OD gearbox. Went out with a tape
measure a few min. ago & can report that both measure 30" from the
bellhousing to the drive shaft flange. Wish I had a TR3 gearbox handy to
give you a full comparison! Maybe someone else can check theirs or you
can use this to check against yours.
If yours is somehow a half inch longer, I am sure you could ovalize the
rear mounting holes, but I would be a bit concerned about the
driveshaft. Maybe you just got a bad set of engine mounts. I think
Revington TR offers urethane mounts.
While we're on the subject, one diff. between the gearboxes (besides the
OD) is a much beefier flange on the bellhousing of the rebuilt unit.
>From this plus odd locations of the OD cutout switches on the top cover,
I am guessing this is actually a much later unit, maybe 4A, 250 or 6 (or
Dolomite or ???). Anyone know about the change point for the heavier
flange on the bellhousing? From markings on the packaging when I got the
rebuilt unit (without the OD), I think it was overhauled in England.
One thing that concens me about the rebuilt gearbox is that the input
shaft "nose", where it fits up to the "spigot" bushing in the rear of
the crankshaft. It's a full half inch shorter than the one on the old
box! (machined length is about 3/4" on the newer one, compared to
approx. 1-1/4" on the old). Looks to me like there won't be a lot
(1/4-1/2"??) meshing between the input shaft and the crankshaft. Anyone
have any comments or opinions? Should I be concerned?
Dave Massey mentioned 5 speed conversions. Just noticed in the latest
Grassroots Motorsports Mag that XKs Unlimited is now an "exclusive
supplier" of complete conversion kits for most LBCs, including our TRs.
Kits are priced from $1999. www.xks.com fyi
Happy holidays!
Alan Myers
San Jose, Calif.
'62 TR4 CT17602L (guaranteed Y3K compliant!)
Bill Brewer wrote:
>
> Hey Fred,
> In addtion to your question, I have a question too. I just had a TR-6
> A-type OD installed in my TR-3. After installation, one of the front motor
> mounts broke. I installed new motor mounts and life is bliss. The old 3 is
> like another car now.
> I ran with a TR-4 non-OD trans for years and was told that the units
> were the same size as the OD units. My engine is kind of lunging forward on
> the motor mounts now (and probably before too). Should I have elongated the
> rear trans mount holes or forward engine mounts? It all seems to be working
> alright now.
> Any listers have suggestions?
>
> Bill Brewer
> Bear Valley Springs (Tehachapi), CA - like anyone knows where the hell
> Tehachapi is anyway...
> -----Original Message-----
> From: Fred Thomas <vafred@erols.com>
> To: triumphs@autox.team.net <triumphs@autox.team.net>
> Date: Monday, December 27, 1999 5:53 AM
> Subject: trans. mounts
>
> >
> >Listers, I have a fellow T/R 3 owner call last night for info about a 64
> T/R
> >4 tranny w/O.D. (type A) he wants to put in his "3", seems the tranny is
> >about 1/2" longer than the rear trans. mount, need some advice as to the
> >best & safest way to complete this project, (no the O/D is not for sale),
> >should the mounts be moved back the 1/2" and will this in anyway weaken the
> >frame set-up. Thanks. "FT"
> >
--
MZ
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