transmision swap

[rktmn]

Need some help.
I have a 93 atx with 64,000 miles, and I picked up a rear ended 93 mtx for the tranny. I have pulled everything out of the mtx and I plan to start the transplant next month. Can I keep the serpentine belt and the accesories from the 3.2 when I change the motor mounts? Will the pulleys line up? What is a good heavy duty street clutch with good street manners? I do not race, but I drive fast and like to go through tht gears. I got a full machine shop in my house so I can fabricate pretty much anything I need. Should I swap the heads from the 3.0 or just the cams? Is it worth it? The mtx motor has 105,000 mi. How can I tell if the cams are not worn?
Any and all advice will be appreciated.

 

[sdpatt]

It's not quite that simple. The entire engine mounting location and driveshaft mountings are different between the MTX and the ATX versions of the SHO. This is not a swap that can be accomplished without MAJOR surgery. It would probably be cheaper to buy a manual transmission SHO.

 

[billh]

Scott
Would it be possible to swap the subframe from the MTX car to locate everything properly? I agree that this swap is probably not practical, but I have to think that if someone hated the ATX as much as I hate mine, they would try. (Personally, I am keeping an eye out for a 94 or 95 SHO MTX car in the Pacific Northwest).
wink

 

[NorthernSHO]

I believe that Al Fritz is trying this swap, check back through old posts about this and see what you find. I'd be very interested if anyone every actually does this swap to find out how much it costs and what steps were taken. Keep us informed of your progress.

Brett

 

[Mr Anonymous]

There are reportedly a number of people attemting ATX-MTX conversions, but I don't believe anyone has reported back here successfully yet.

The general consensus seems to be the following:

1. The 3.2 short block is built-up with all of the 3.0 components (heads, flywheel, accy's, etc.) as if you were doing a straight 3.2 upgrade to an MTX.

2. The clutch pedal & cable have to be installed in the ATX (the mounting points and cable bushings are there).

3. The shifter has to be installed in the ATX, which would require cutting a new hole in the floorpan astern of the hole for the ATX shifter.

4. The A/C lines would have to be replaced with the MTX versions since the compresser will be moving back in the engine compartment a couple of inches.

5. The reassembled motor & MTX tranny are installed on the MTX subframe, which would then be installed from the bottom (or you could mount the subframe first & do it from the top).

5a. The MTX Y-Pipe and catback (at least through the resonator) would be installed.

6. The ATX EEC would have to be replaced with an MTX EEC.

7. A lot of skill, patience, luck, and prayer!

Now, having spent an inordinate amount of time on a creeper beneath a couple of SHO's lately, I've been thinking that the following MIGHT be possible:

1. Swap out the flywheel & tranny, keeping the ATX subframe, engine, accy's, y-pipe, etc.

2. Install the clutch pedal & cable.

3. Install a CABLE shifter, which might fit in the ATX mount and reach the tranny (the shifter would be further forward than in a stock MTX, but not out of reach).

4. Swap out the ATX EEC for an MTX EEC.

5. This is COMPLETELY THEORY/GUESSWORK in my mind! wink (I welcome any thoughts on this though!)

<small>[ August 30, 2002, 04:28 PM: Message edited by: SHOooo ]</small>

 

[rktmn]

If you go to www.shotimes.com/SHO4engineswap.html there is an article with photos of a 3.2 auto engine installed on a manual transmission car by Tim Dahn. If it is possible to drop the auto engine in an mtx sho, it should be possible to install the manual tranny in an atx.

I have already stripped the donor mtx completely down to the wire harness. I plan to move the entire subframe, mtx transmission, driveshafts, spindles, brakes, etc. over to my atx sho. First, of course, I would drop the entire subframe and transmission from the atx, leaving the engine hanging from the hoist.
I would need to transplant the oil pan, perhaps the oil pump, starter, motor mounts, flywheel, clutch, pressure plate, ovedr to the 3.2.

So far this should allow the engine, manual transmission, subframe and suspension to be attached to the atx car. The brake, and clutch pedal assembly wil bolt up to the existing holes. The hole for the cluthch cable is already there. Cutting the hole for the shifter on the floor board is no ploblem. Using the atx computer should be no problem either (I think) since I would still be using the atx engine. I would have to jump the clutch interlock switch.

My question is, could I keep the serpentine pulley system from the atx onece I install the mtx motor mounts, or would I be forced to bring over all the pullies and accesories, including the timing belt tensioner from the mtx donor engine?

I have already begun the project, so there is no turning back back now, since my atx has been slipping for the last couple of months.

 

[snake396]

you have to convert over to an MTX computer, because the automatic transmission is controled by the computer. without the trans to talk to, it would sort of be stumbling over itself. about the accessory drive, i don't know, but the general consensus seems to be that you have to swap.

 

[RStalveyARFF]

rktmn:
If you go to www.shotimes.com/SHO4engineswap.html there is an article with photos of a 3.2 auto engine installed on a manual transmission car by Tim Dahn. If it is possible to drop the auto engine in an mtx sho, it should be possible to install the manual tranny in an atx.

I have already stripped the donor mtx completely down to the wire harness. I plan to move the entire subframe, mtx transmission, driveshafts, spindles, brakes, etc. over to my atx sho. First, of course, I would drop the entire subframe and transmission from the atx, leaving the engine hanging from the hoist.
I would need to transplant the oil pan, perhaps the oil pump, starter, motor mounts, flywheel, clutch, pressure plate, ovedr to the 3.2.

So far this should allow the engine, manual transmission, subframe and suspension to be attached to the atx car. The brake, and clutch pedal assembly wil bolt up to the existing holes. The hole for the cluthch cable is already there. Cutting the hole for the shifter on the floor board is no ploblem. Using the atx computer should be no problem either (I think) since I would still be using the atx engine. I would have to jump the clutch interlock switch.

My question is, could I keep the serpentine pulley system from the atx onece I install the mtx motor mounts, or would I be forced to bring over all the pullies and accesories, including the timing belt tensioner from the mtx donor engine?

I have already begun the project, so there is no turning back back now, since my atx has been slipping for the last couple of months.

You need a full AC system from an MTX, the drier is located in the back corner of an ATX, it's in the front corner of an MTX. you'll also need to swap to an MTX fan and shroud, get a 180 t-stat, and transfer the ENTIRE front half of the 3.0 onto the 3.2 . The only piece you can keep is the timing belt cogs for the cams, as well as the cog down on the crankshaft for the t-belt. You can't keep the serpentine belt system, it will not fit. Drop the motor with the subframe and tranny, it will be alot easier to work on. You will also need to use the MTX wiring harness, MTX fuel rails, MTX injectors on the car. Sensors are in different locations on the 3.2 ATX opposed to the 3.2 MTX. You must used the MTX EEC, there are different injector sizes/commands between the two combos. You're in for a long, hard project.

<small>[ September 01, 2002, 09:13 PM: Message edited by: SHO91MTX ]</small>

 

[billh]

SHO91MTX:

rktmn:
If you go to www.shotimes.com/SHO4engineswap.html there is an article with photos of a 3.2 auto engine installed on a manual transmission car by Tim Dahn. If it is possible to drop the auto engine in an mtx sho, it should be possible to install the manual tranny in an atx.

I have already stripped the donor mtx completely down to the wire harness. I plan to move the entire subframe, mtx transmission, driveshafts, spindles, brakes, etc. over to my atx sho. First, of course, I would drop the entire subframe and transmission from the atx, leaving the engine hanging from the hoist.
I would need to transplant the oil pan, perhaps the oil pump, starter, motor mounts, flywheel, clutch, pressure plate, ovedr to the 3.2.

So far this should allow the engine, manual transmission, subframe and suspension to be attached to the atx car. The brake, and clutch pedal assembly wil bolt up to the existing holes. The hole for the cluthch cable is already there. Cutting the hole for the shifter on the floor board is no ploblem. Using the atx computer should be no problem either (I think) since I would still be using the atx engine. I would have to jump the clutch interlock switch.

My question is, could I keep the serpentine pulley system from the atx onece I install the mtx motor mounts, or would I be forced to bring over all the pullies and accesories, including the timing belt tensioner from the mtx donor engine?

I have already begun the project, so there is no turning back back now, since my atx has been slipping for the last couple of months.

You need a full AC system from an MTX, the drier is located in the back corner of an ATX, it's in the front corner of an MTX. you'll also need to swap to an MTX fan and shroud, get a 180 t-stat, and transfer the ENTIRE front half of the 3.0 onto the 3.2 . The only piece you can keep is the timing belt cogs for the cams, as well as the cog down on the crankshaft for the t-belt. You can't keep the serpentine belt system, it will not fit. Drop the motor with the subframe and tranny, it will be alot easier to work on. You will also need to use the MTX wiring harness, MTX fuel rails, MTX injectors on the car. Sensors are in different locations on the 3.2 ATX opposed to the 3.2 MTX. You must used the MTX EEC, there are different injector sizes/commands between the two combos. You're in for a long, hard project.

Reminds me of doing a "radiator cap job" - Jacking up the radiator cap and driving another car under it! wink
Kind of goes back to what most everyone has been saying all along. Far less trouble just to replace the car!