Bellhousing adapters?

[mlemorie]

Was doing some digging around companies that make adapters and found that the gearbox I have isn't too popular to swap into anything. I have an Isuzu MSG-5 that I want to put behind an engine. Is there any company making custom adapters that won't break the bank? I have a second transmission that I could send out to be used for reference as well.

 

[oilhammer]

Is there something very specific to THAT transmission that you are hung on? What was it originally used in?

 

[mlemorie]

It's the 5mt that is currently in my diesel chevette. If I'm able to use it, that makes the MTDI swap much more straight forward. Plus I have a spare if needed lol.

 

[oilhammer]

Ah, OK, that makes sense. I had one of those. Great engine, absolutely miserable car. And bad structural rust, yours has I guess not lived its whole life in Michigan?

Anyway, the issue becomes.... is it easier to custom make an adapter for a transmission in one instance, or easier to use one for a much more common transmission like one of the Aisin boxes or the Mazda units in Fords? Those are likely to be bigger transmissions, though, and the Chevette's tunnel is pretty tiny from what I remember.

 

[mlemorie]

Parts were near impossible to find for the little 4fb1 15 years ago when I picked this thing up lol. It has some rust but isn't actually terrible. It's been taking up space in my garage for the last 10 years. It is a small tunnel without much wiggle room. Thinking that it is probably easier in the long run to adapt the engine to the trans instead of adapting the engine to a different trans, and then also adapting the car to that new trans. At least for now anyway. I know I'm an oddball, but I have a soft spot for weird cars and doing things with them that shouldn't be done. Even with my RC stuff, I got a race class put together for probably one of the worst handling vehicles because it was fun lol

 

[Alberta 7.3]

Those diesel Chevettes were quite rare, I only knew they existed because I saw one at a u-pull 25 years ago. A bit of google search and it sounds like they may have used a Borg-Warner T5 transmission. The T5 was used on quite a few brands and models of vehicles. You may be able to swap the bell housing to something that an adapter is commonly available for, which might entail also swapping the input shaft.

 

[PickleRick]

The t5 would need more than a bell swap most likely. Add a matching input shaft then internal gears.


You'd likely be better off running a Chevy 5 speed 2wd transmission found behind the 2.8v6 or preferably the 4.3 as there are already 60 and 90 Chevy adapters.


Then there are the 2wd 22re/3.0 and 3.4 Toyota pickup/supra 5 speeds with readily available adapters. The Yota transmission would be the my choice out of these, aisin as @oilhammer suggested.



All are small 5 speeds.




I realize you already have the transmission and it could POSSIBLY save you a custom or modified drive shaft but there's a good chance your transmission won't be able to stay in the same spot anyway.


The t5 wasn't known for reliability, the V8 swapped guys ate them up pretty quickly and eventually upgraded. I don't know how much power you plan on putting down on your mtdi

 

[mlemorie]

Those diesel Chevettes were quite rare, I only knew they existed because I saw one at a u-pull 25 years ago. A bit of google search and it sounds like they may have used a Borg-Warner T5 transmission. The T5 was used on quite a few brands and models of vehicles. You may be able to swap the bell housing to something that an adapter is commonly available for, which might entail also swapping the input shaft.

That's the same info I found online as well, but it is incorrect. It's definitely an isuzu gearbox. I'm glad I've got two of them so I don't have to strip the car to try and come up with an adapter lol

 

[mlemorie]

The t5 would need more than a bell swap most likely. Add a matching input shaft then internal gears.


You'd likely be better off running a Chevy 5 speed 2wd transmission found behind the 2.8v6 or preferably the 4.3 as there are already 60 and 90 Chevy adapters.


Then there are the 2wd 22re/3.0 and 3.4 Toyota pickup/supra 5 speeds with readily available adapters. The Yota transmission would be the my choice out of these, aisin as @oilhammer suggested.



All are small 5 speeds.




I realize you already have the transmission and it could POSSIBLY save you a custom or modified drive shaft but there's a good chance your transmission won't be able to stay in the same spot anyway.


The t5 wasn't known for reliability, the V8 swapped guys ate them up pretty quickly and eventually upgraded. I don't know how much power you plan on putting down on your mtdi

The Toyota boxes were my original choice as well way back when I first started tinkering with this idea and had aspirations of higher power. For now I just want to get this thing put together and driveable. Stock ALH with mechanical pump swap and my T25 turbo if I can find it lol. I think the trans has a pretty good shot of being able to use its factory mounts. The isuzu engine had a belt fan on the front, and I'm going to swap to electric anyway so I have a good chunk of space in front of the engine to work with.

 

[mlemorie]

Alright back again! So I’ve been gathering parts and digging up info these past few weeks, and here is what I’ve come up with so far: Late model gas chevettes did indeed get a T5 gearbox and not the same Isuzu box I have. That was a diesel only gearbox aaaaaand it’s weak as balls lol. So it looks like I’ll be trying to get my hands on the shorty T5 box and adapting to that instead, as the t5 apparently will fit in the earlier body tunnels without issue. So that brings us up to speed on this front. I’ve seen the Lakewood bell housing that will adapt the engine directly to a gearbox, and I’ve also seen the td conversions 60 degree gm adapter kit. My alh actually came with a small block Chevy adapter already attached to it and I assume I could find an old Camaro bell housing and attach the gearbox that way, but that still leaves me with a large bell housing taking up extra space. The Lakewood unit is nice and compact, but I’m having trouble discerning if that would work with a gm t5 as the reading I’ve done so far has pointed it at being ford t5 compatible. Also I haven’t seen anything about what angle that sets the engine at and whether or not it will let me clock the engine as needed for clearance. That kinda points me towards the td kit for the V6, as that should let me bolt up the tiny t5 with a smaller bellhousing AND let my clock the engine as needed. Thoughts? I’m going to grab some pictures of my adapter shortly and see if anyone here might recognize it. It doesn’t have any company name on it, and it’s been hand scribed “small block Chevy” on both the transmission plate and the flywheel adapter. Maybe someone can help me identify that particular unit.

 

[mlemorie]

Scratch that. Apparently the chevette box uses the ford pattern. Found in an opel group of all places lol.

 

[Alberta 7.3]

tdconversions.com usually engrave the plate with what it is to adapt to.

 

[mlemorie]

tdconversions.com usually engrave the plate with what it is to adapt to.

Theirs look nicely machined, I was wondering if it may be an older unit of theirs from before they updated production methods or something. I'll attach some pictures I grabbed soon, just have to get them hosted.

As for gearboxes, it looks like I need to start getting some measurements of shifter locations and bellhousing depths on different T5s. Going to have to mix and match a bit to figure out what combination will end up with the engine, shifter, and output shaft close to where I need them. I emailed lakewood about the bellhousing for some dimensions and whether or not it allows for clocking the gearbox but I haven't heard back yet. That TKX looks nice too, but I'm not too keen on almost 3k for a box. That's 5x what I paid for thr car lol

 

[mlemorie]

Finally. Far more difficult to host and post this picture than it ever should have been. Apparently imgur just tells mobile browsers to pound sand now. So the smaller piece that bolts to the engine almost appears to be a cast piece going off the texture of the spacer section of it, and the main piece seems like a cut out and not machined. Still seems like a decent adapter, but it bugs me that it uses SAE hardware lol. Took me forever to dig through my tools to take it apart.

 

[Mozambiquer]

I wish I had one of those manual transmissions years ago when I had my diesel chevette. Mine was an automatic. Paid $500 for it at a junkyard with very little rust, but a bad flex plate. The replacement flex plate was in the back seat along with the transmission. That was one of those cars that made my 1.6 diesel rabbits feel fast.

 

[mlemorie]

I’m hoping to fix that speed issue with the ALH lol

 

[caffeine]

Scratch that. Apparently the chevette box uses the ford pattern. Found in an opel group of all places lol.

There are some other GM T5s that use the 'Ford' pattern, but the input shaft bearing retainer O.D. is different than the Ford O.D., so maybe check what the Chevette T5 uses before picking a bellhousing. The 94-95 S10 2.2 T5 uses the Ford bellhousing-trans pattern, has the GM Metric bellhousing pattern used on the 60*V6 and others, and is designed for a transmission mounted straight up. 93+ F-body T5 bellhousings also use the 'Ford' bellhousing-trans pattern, have the Metric bellhousing pattern, but are meant for a transmission mounted on an angle (I wanna say 15* off the top of my head). 3rd-Gen F-body and 1st Gen S-truck T5 bellhousings use the GM pattern; all F-body bellhousings are meant for a transmission mounted on an angle. There's also a unicorn Astro van T5 bellhousing that uses the GM pattern, is meant for a transmission mounted straight up, and has the SBC bellhousing pattern.

I suppose you may or may not want the angled bellhousing depending on how the engine is going to sit.