Some 4x4 enthusiasts were discussing an engine swap that would use an
aluminum bellhousing that had a 1.00" section removed and the rear face
then welded back on and trued up on a milling machine. A jig was to be
used to keep the alignment of the front and rear faces in the proper
relationship.

My question regards the feasability of welding something like this. Can
an aluminum bellhousing welded like this be considered safe and strong
enough to use in a vehicle?

I am pretty sure parts like this are cast, machined and then heat
treated when they are produced by the original manufacturer. I guess I'm
concerned that major welding on this unit is not a good idea.

Fred

"F. Hayek" wrote in message
...
Some 4x4 enthusiasts were discussing an engine swap that would use an
aluminum bellhousing that had a 1.00" section removed and the rear face
then welded back on and trued up on a milling machine. A jig was to be
used to keep the alignment of the front and rear faces in the proper
relationship.

My question regards the feasability of welding something like this. Can
an aluminum bellhousing welded like this be considered safe and strong
enough to use in a vehicle?

I am pretty sure parts like this are cast, machined and then heat
treated when they are produced by the original manufacturer. I guess I'm
concerned that major welding on this unit is not a good idea.

Fred

I don't doubt the strength, but I'd sure as hell question the ability to end
up with the pilot bearing in the crank concentric with the main bearing in
the trans. One that is not is likely to be the cause of premature clutch
failures, as well as bearing failures. Even if a fixture locates the
two halves properly, I can't imagine that the welding process would leave
them where they were desired. I would worry about that more than the
strength, especially if the welding is in the hands of a good weldor. Is
this a case of re-machining the bore of the bell housing , too?

Harold.

In article , F.
Hayek wrote:

Some 4x4 enthusiasts were discussing an engine swap that would use an
aluminum bellhousing that had a 1.00" section removed and the rear face
then welded back on and trued up on a milling machine. A jig was to be
used to keep the alignment of the front and rear faces in the proper
relationship.

My question regards the feasability of welding something like this. Can
an aluminum bellhousing welded like this be considered safe and strong
enough to use in a vehicle?

I am pretty sure parts like this are cast, machined and then heat
treated when they are produced by the original manufacturer. I guess I'm
concerned that major welding on this unit is not a good idea.

Fred

It could be done, and accurately, but would take a bit of skill.
The welding be be easiest if the bell housing was relatively new so it
didn't have a decode of oil saturated into the porous surface of the
casting.

The jig that aligned the 2 surfaces would be critically important.
The welding would take some time as it couldn't be done too fast
without cracks forming around the weld area.

I though these adpater bell housings were already available off the
shelf for a few $100.

I don't doubt the strength, but I'd sure as hell question the ability to
end
up with the pilot bearing in the crank concentric with the main bearing in
the trans. One that is not is likely to be the cause of premature clutch

FWIW,

My son's mustang needed a different bell housing, and the only one we could
find in the salvage yard was severely cracked. I welded it up and then had
to re-machine clearance for the ring gear. Worried about just this problem,
I bolted the bellhousing to the engine, and then slid the tranny on where I
could feel the fit into the pilot bearing, I got lucky, it was perfect. My
"plan B" would have been to pin the tranny where it needed to be and redrill
and tap new hold down bolts. (This idea wouldn't work on GM products - the
bell housing and tranny are one piece)

The car ran with this real well, till he blew up his Crate engine. Right now
the engine is in pieces in the shop waiting for funds. ( Me thinks this is a
good thing - maybe the kid won't blow the next one so soon) In the mean
time, the kid drives my old minivan.

Karl

In article ,
Ernie Leimkuhler wrote:

I though these adpater bell housings were already available off the
shelf for a few $100.

Not for this application. What I'm trying to do is mate up a Toyota
Supra Turbo 7M-GTE motor with an R series transmission in a Toyota
pickup truck. The Turbo Supras also used R series trannys but they had a
longer inputshaft (+30mm) than the R series truck trannys (same diameter
and spline though). The Supra tranny is undesirable for 4x4 trucks
because it has a higher first gear and you can't change that gear
without changing the input shaft to a truck input, which would then be
too short. The truck trannys will bolt right up to a Supra bellhousing
but the input shaft will be 30mm too short. A pilot bearing adapter that
moved the pilot bearing 30mm out to the input shaft seems like it would
interfere with the clutch disk hub.

The most desirable R series truck transmission has a 4.31 to 1 first
gear and the Supra tranny has a 3.21 to 1 first gear.

The 5 sp. transmission used in a 1996 or later Tacoma is also an R
series and it will also bolt right up to the Supra bellhousing, but, it
has a different tail housing (for mounting the transfer case). A company
called Marlin Crawler makes an excellent adapter to mate the correct
tranfer case to this transmission for $349, but (yes another but) the
first gear ratio in the Tacoma trans is 3.89 to 1, which is better than
the Supra ratio and not as good as the earlier transmission with the
4.31 ratio. There is no gearset available to change the ratio in the
Tacoma trans to a lower ratio as Toyota changed the helical cut on the
gears in 1996.

It would be possible to have a longer custom input shaft made, but these
inputs also have and integral bearing race and a gear; they are not just
a simple shaft, so a "one off" job might be prohibitively expensive
(although I'd welcome input on that).

The easy answer looks to be a stock Supra bellhousing and clutch, Tacoma
transmission, a $349 transfercase adapter and live with the 3.89 first
gear. My only worry is that the Supra motor, while it has good low end
torque, displaces only 3.0 liters and probably could benefit from a
lower first gear in this application. I guess it works well enough in
the Tacoma behind the 3.4 V6, but heck I want to do better than stock :-)

Fred

On Sat, 07 Feb 2004 22:58:03 -0600, "F. Hayek" wrote:
Some 4x4 enthusiasts were discussing an engine swap that would use an
aluminum bellhousing that had a 1.00" section removed and the rear face
then welded back on and trued up on a milling machine. A jig was to be
used to keep the alignment of the front and rear faces in the proper
relationship.

My question regards the feasability of welding something like this. Can
an aluminum bellhousing welded like this be considered safe and strong
enough to use in a vehicle?

I am pretty sure parts like this are cast, machined and then heat
treated when they are produced by the original manufacturer. I guess I'm
concerned that major welding on this unit is not a good idea.

Ron Millen had to splice parts from two bellhousings to mate up a 4.5 l
V8 to a Toyota 6 speed manual tranny for his IS300 project. The trick
his guys used to make sure everything would line up is they machined
steps in the mating parts so they had to go together right.

Aluminum bellhousings are normally used as cast with no post-heat
treatment. So welding one shouldn't make it weaker. They're normally
thick enough to have sufficient strength without such treatment.

Gary

On Sat, 07 Feb 2004 22:58:03 -0600, "F. Hayek"
wrote:

Some 4x4 enthusiasts were discussing an engine swap that would use an
aluminum bellhousing that had a 1.00" section removed and the rear face
then welded back on and trued up on a milling machine. A jig was to be
used to keep the alignment of the front and rear faces in the proper
relationship.

My question regards the feasability of welding something like this. Can
an aluminum bellhousing welded like this be considered safe and strong
enough to use in a vehicle?

I am pretty sure parts like this are cast, machined and then heat
treated when they are produced by the original manufacturer. I guess I'm
concerned that major welding on this unit is not a good idea.

Fred
As others have said, welding, if done properly, will be OK. The real
problem is getting everything parallel and concentric. When I put a
buick V6 into my '52 jeep the store bought adapter was not concentric.
There was enough slop in the tranny input shaft to slip in but it
rubbed on the nose piece. I had to fix the adapter. But the bell
housing also needed work so I put it on my mill and machined the face
and changed the bore. You would probably be wise to do this. Make a
fixture to align the bell housing for welding and then check in a
mill. If it's out the use the setup to bore and mill it. Then, because
the bore is bigger, make a ring to press in that brings it back to
original size. Or weld in the bore and machine that out. I'd make the
ring. And make it so when the bell housing is bolted to the tranny it
is trapped and cannot work it's way out.
ERS

|It would be possible to have a longer custom input shaft made, but these
|inputs also have and integral bearing race and a gear; they are not just
|a simple shaft, so a "one off" job might be prohibitively expensive
|(although I'd welcome input on that).

The Supra transmission input shaft won't fit the Tacoma transmission ?
Rex in Fort Worth

In article ,
(Rex B) wrote:

The Supra transmission input shaft won't fit the Tacoma transmission ?
Rex in Fort Worth


The Supra shaft has an integral gear that has a different helical cut in
it than the gears in the Tacoma transmission. You can't change the
counter gear either because it is part of the counter shaft.

Fred

In article , F.
Hayek wrote:

In article ,
Ernie Leimkuhler wrote:

I though these adpater bell housings were already available off the
shelf for a few $100.

Not for this application. What I'm trying to do is mate up a Toyota
Supra Turbo 7M-GTE motor with an R series transmission in a Toyota
pickup truck. The Turbo Supras also used R series trannys but they had a
longer inputshaft (+30mm) than the R series truck trannys (same diameter
and spline though). The Supra tranny is undesirable for 4x4 trucks
because it has a higher first gear and you can't change that gear
without changing the input shaft to a truck input, which would then be
too short. The truck trannys will bolt right up to a Supra bellhousing
but the input shaft will be 30mm too short. A pilot bearing adapter that
moved the pilot bearing 30mm out to the input shaft seems like it would
interfere with the clutch disk hub.

The most desirable R series truck transmission has a 4.31 to 1 first
gear and the Supra tranny has a 3.21 to 1 first gear.

The 5 sp. transmission used in a 1996 or later Tacoma is also an R
series and it will also bolt right up to the Supra bellhousing, but, it
has a different tail housing (for mounting the transfer case). A company
called Marlin Crawler makes an excellent adapter to mate the correct
tranfer case to this transmission for $349, but (yes another but) the
first gear ratio in the Tacoma trans is 3.89 to 1, which is better than
the Supra ratio and not as good as the earlier transmission with the
4.31 ratio. There is no gearset available to change the ratio in the
Tacoma trans to a lower ratio as Toyota changed the helical cut on the
gears in 1996.

It would be possible to have a longer custom input shaft made, but these
inputs also have and integral bearing race and a gear; they are not just
a simple shaft, so a "one off" job might be prohibitively expensive
(although I'd welcome input on that).

The easy answer looks to be a stock Supra bellhousing and clutch, Tacoma
transmission, a $349 transfercase adapter and live with the 3.89 first
gear. My only worry is that the Supra motor, while it has good low end
torque, displaces only 3.0 liters and probably could benefit from a
lower first gear in this application. I guess it works well enough in
the Tacoma behind the 3.4 V6, but heck I want to do better than stock :-)

Fred

Believe it or not I get it.

A custom Bellhousing could be done, but it requires high skill.
I know I could do it, but I would have trouble finding more than 2
other people I know who could do it.

On Mon, 09 Feb 2004 19:44:39 GMT, Ernie Leimkuhler wrote:

|In article , F.
|Hayek wrote:
|
| In article ,
| Ernie Leimkuhler wrote:
|
| I though these adpater bell housings were already available off the
| shelf for a few $100.
|
| Not for this application. What I'm trying to do is mate up a Toyota
| Supra Turbo 7M-GTE motor with an R series transmission in a Toyota
| pickup truck. The Turbo Supras also used R series trannys but they had a
| longer inputshaft (+30mm) than the R series truck trannys (same diameter
| and spline though). The Supra tranny is undesirable for 4x4 trucks
| because it has a higher first gear and you can't change that gear
| without changing the input shaft to a truck input, which would then be
| too short. The truck trannys will bolt right up to a Supra bellhousing
| but the input shaft will be 30mm too short. A pilot bearing adapter that
| moved the pilot bearing 30mm out to the input shaft seems like it would
| interfere with the clutch disk hub.
|
| The most desirable R series truck transmission has a 4.31 to 1 first
| gear and the Supra tranny has a 3.21 to 1 first gear.
|
| The 5 sp. transmission used in a 1996 or later Tacoma is also an R
| series and it will also bolt right up to the Supra bellhousing, but, it
| has a different tail housing (for mounting the transfer case). A company
| called Marlin Crawler makes an excellent adapter to mate the correct
| tranfer case to this transmission for $349, but (yes another but) the
| first gear ratio in the Tacoma trans is 3.89 to 1, which is better than
| the Supra ratio and not as good as the earlier transmission with the
| 4.31 ratio. There is no gearset available to change the ratio in the
| Tacoma trans to a lower ratio as Toyota changed the helical cut on the
| gears in 1996.
|
| It would be possible to have a longer custom input shaft made, but these
| inputs also have and integral bearing race and a gear; they are not just
| a simple shaft, so a "one off" job might be prohibitively expensive
| (although I'd welcome input on that).
|
| The easy answer looks to be a stock Supra bellhousing and clutch, Tacoma
| transmission, a $349 transfercase adapter and live with the 3.89 first
| gear. My only worry is that the Supra motor, while it has good low end
| torque, displaces only 3.0 liters and probably could benefit from a
| lower first gear in this application. I guess it works well enough in
| the Tacoma behind the 3.4 V6, but heck I want to do better than stock :-)
|
| Fred
|
|Believe it or not I get it.
|
|A custom Bellhousing could be done, but it requires high skill.
|I know I could do it, but I would have trouble finding more than 2
|other people I know who could do it.

These guys can do it: www.taylor-race.com
Craig Taylor is the nicest and most knowledgable guy you will meet on
performance drivetrains. Located in the DFW area, but ships all over the world
Rex in Fort Worth