MG engine/trans swap
07-02-03, 02:55 PM
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MG engine/trans swap
Still learning where everything is around here.
I posted this in another forum before I found this one. Hopefully this will get some more views.
I'm looking to do a MG engine/trans swap. Which motor to use, tips, suggestions, things to look out for, would be appreciated.
Not looking for anything obnoxious power wise. The car currently has around 70 hp and weighs around 1600 lbs. Turbo is desired, possibly overkill (if that's possible) but not a necessity. I'm looking for an old RX-7 that could be used for a donor. That way I could get all the wiring, linkages, etc...
Things to look for or watch out for when buying an old rotary would also be apprectiated.
Thanks.
I posted this in another forum before I found this one. Hopefully this will get some more views.
I'm looking to do a MG engine/trans swap. Which motor to use, tips, suggestions, things to look out for, would be appreciated.
Not looking for anything obnoxious power wise. The car currently has around 70 hp and weighs around 1600 lbs. Turbo is desired, possibly overkill (if that's possible) but not a necessity. I'm looking for an old RX-7 that could be used for a donor. That way I could get all the wiring, linkages, etc...
Things to look for or watch out for when buying an old rotary would also be apprectiated.
Thanks.
07-02-03, 03:06 PM
#2
Oh good, you found it. 
Hmm, you could easily get away with a 12A out of a 1st gen. Apearantly, the tranny mount will bolt to the stock MG mount location. All you have to do is fabricate a front motor mount. Personally, I'd chop off the ends of the stock mount and align it in the engine bay. Then tack on some angle iron pieces and run a full bead and you're done. Also, the stock pan can be used if you aren't affraid to bend the sheet metal of the frame rails downward to the clear the sump. You'll also have to chop out a very small section to clear the drain plug. Just fill that section with a curved piece of mild steel welded in place. Or just have a new drain plug bung welded in the back or front of the pan. The 12A intake manifold and carb can be used if you hack off one of the heat shield holders. A '79-'82 radiator can be used if you relocate the lower water tube to the middle so it fits near the lower rounded section of the car's crossmember or whatever it's called. The steering stuff won't get in the way if you do it like my car. Also a '79-'82 oil cooler can be mounted in front of the rad, right next to the grill. Here's a quick link: http://www.geocities.com/cd23c/cars.html#mg
I'll have more pics with the 13B in it uploaded soon.
Hmm, you could easily get away with a 12A out of a 1st gen. Apearantly, the tranny mount will bolt to the stock MG mount location. All you have to do is fabricate a front motor mount. Personally, I'd chop off the ends of the stock mount and align it in the engine bay. Then tack on some angle iron pieces and run a full bead and you're done. Also, the stock pan can be used if you aren't affraid to bend the sheet metal of the frame rails downward to the clear the sump. You'll also have to chop out a very small section to clear the drain plug. Just fill that section with a curved piece of mild steel welded in place. Or just have a new drain plug bung welded in the back or front of the pan. The 12A intake manifold and carb can be used if you hack off one of the heat shield holders. A '79-'82 radiator can be used if you relocate the lower water tube to the middle so it fits near the lower rounded section of the car's crossmember or whatever it's called. The steering stuff won't get in the way if you do it like my car. Also a '79-'82 oil cooler can be mounted in front of the rad, right next to the grill. Here's a quick link: http://www.geocities.com/cd23c/cars.html#mg
I'll have more pics with the 13B in it uploaded soon.
Last edited by Jeff20B; 07-02-03 at 03:09 PM.
03-10-04, 05:05 AM
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Well, I don't have experience with the swap as such, but me too would recommend a 12A.
Actually, look at this: 12A's are relatively cheap, not very complex, and at 115hp stock, very powerfull in comparrison with the original engine.
If, in the end, you want more then 115hp, a better exhaust and a decent carb can bring you to about 150hp (depending on emmission rules). If you still want more, a ported engine will throw in another few ponnies.
However, an old style (pre RX7) 13B engine would also be rather simple, yet a bit more expensive and rather uncommon to find used. It'll either be a rebuild (expensive) or a piece of crap, due to age. 12A's are still easily found in good condition, they are not that old yet. Even if it's getting a bit harder overhere.
Since the small size of rotary engines, the swap itself shouldn't be that hard: they'll fit almost any engine bay.
Good luck, and keep posting about the progress!
Actually, look at this: 12A's are relatively cheap, not very complex, and at 115hp stock, very powerfull in comparrison with the original engine.
If, in the end, you want more then 115hp, a better exhaust and a decent carb can bring you to about 150hp (depending on emmission rules). If you still want more, a ported engine will throw in another few ponnies.
However, an old style (pre RX7) 13B engine would also be rather simple, yet a bit more expensive and rather uncommon to find used. It'll either be a rebuild (expensive) or a piece of crap, due to age. 12A's are still easily found in good condition, they are not that old yet. Even if it's getting a bit harder overhere.
Since the small size of rotary engines, the swap itself shouldn't be that hard: they'll fit almost any engine bay.
Good luck, and keep posting about the progress!
03-10-04, 09:23 AM
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Seems like most have done it with the 13b though..
HMM.... decisions, decisions.
Any other thoughts on 12a VS 13b ??
Wouldn't mind 200+ hp
My car is solid the way it is, but the engine needs a rebuild anyways...and it's still way too slow and strains that little sewing machine just to keep up on the highways.
HMM.... decisions, decisions.
Any other thoughts on 12a VS 13b ??
Wouldn't mind 200+ hp
My car is solid the way it is, but the engine needs a rebuild anyways...and it's still way too slow and strains that little sewing machine just to keep up on the highways.
03-10-04, 11:43 AM
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it'll just depend on costs and work. If you really want a lot of HP, you could use a TII (although you should check if there's enough space for the turbo).
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03-10-04, 12:18 PM
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This site almost gives you a step by step on how to do it:
http://www.etischer.com/
http://www.etischer.com/
03-11-04, 03:33 PM
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here is a link to some pics of my swap. I went with the 12A, the 13B just didn't seem to fit as easily.
http://www.grassrootsmotorsports.com...pic.php?t=2881
http://www.grassrootsmotorsports.com...pic.php?t=2881
03-11-04, 06:15 PM
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Don't worry, I'll swap the engine as fast as I can. Spring is coming fast and I wanna be driving fast....hehehe
Thank God almighty for this website!!!
I was searching endlessly for MG midget info. and never thought of looking here until last week.
Things are definitly coming together faster now and next week I will have the parts at my buddy's garage so I can get started...Hopefully it won't take too long.
Thanks to all who have helped so far and pictures will be coming soon.
Thank God almighty for this website!!!
I was searching endlessly for MG midget info. and never thought of looking here until last week.
Things are definitly coming together faster now and next week I will have the parts at my buddy's garage so I can get started...Hopefully it won't take too long.
Thanks to all who have helped so far and pictures will be coming soon.
03-11-04, 06:19 PM
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BTW, Awesome pictures on the site.
Amazing how small the car looks when someone is stood next to it HAHA
I'll bet it pulls a lot harder than the stock 65hp!
Nice job.
Amazing how small the car looks when someone is stood next to it HAHA
I'll bet it pulls a lot harder than the stock 65hp!
Nice job.
03-12-04, 08:03 PM
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Right on!
I am starting the conversion in my '68 midget this very weekend and I can't wait to just be done.
That's all you did, right?
Just changing the engine/trans.
I am starting the conversion in my '68 midget this very weekend and I can't wait to just be done.
That's all you did, right?
Just changing the engine/trans.
04-08-04, 12:35 PM
#22
Conversion questions
I have been working on putting an 88 13B into a Bugeye and I have a couple of questions. I am going to use the 6port lower manifold with the actuators. I was told that instead of actuating them off of the header I'd be better off using a remote mounted electric air pump. I am using a electromotive injection system so I could actuate it from there.
I have finished painting it this weekend, and am getting the engine ready for the installation over the next couple of weeks. I am also using a GSL narrowed rear end and was wondering if anyone dealt with making the emergency brake work.
Thanks
I have finished painting it this weekend, and am getting the engine ready for the installation over the next couple of weeks. I am also using a GSL narrowed rear end and was wondering if anyone dealt with making the emergency brake work.
Thanks
04-18-04, 09:42 PM
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Wish you weren't in Canada. I just got my 12a Triumph spitfire conversion running. Took me a month to get it all together, and it is almost good. Make sure any custom exhaust that you make uses 1/8 thick walled tubing, cause stock exhaust pipes turn bright orange with just a few minutes of the engine running. Will fail very soon, I am working on having it replaced. I am using streetported 12a from an 85 Rex.
04-18-04, 11:05 PM
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cool, I hope that works out for you..
Sounds sweet, I used to have a '69 spitfire. With the sloped trunk. Too bad I sold that car...
I'd really like to see a TR6 conversion with a TII
sweeet
I'd really like to see a TR6 conversion with a TII
sweeet
