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I just picked up a 1992 Super Coupe 5 speed. It's in rough shape, but nothing that I can't fix with a bit of help from here. I am a mechanic and I can tackle any job, but I am not skilled with superchargers or transmissions.

The supercharger was bypassed, spinning by hand reveals metallic noises from inside, so I am guessing that it needs a rebuild. What is involved in rebuilding it? I have seen a rebuild kit for the M90 on ebay, but I am wary of most stuff on ebay. The kit contains bearings and seals. Any chance that it will fix my issue, or should I be on the prowl for a junkyard charger?

Secondly, the 2nd and 3rd gear syncros are toast in the transmission. I have searched and I can't seem to find a rebuild kit for it, any suggestions on where to look for one? I have found plenty of them for F150's, but reading the guide here shows that only a few of the parts work for the SC tranny.

Lastly, I have a nice little knock coming from the motor, but it damn sure doesn't sound like a rod to me, plus I found a log book in the car that showed a rebuild on the engine 20K ago. Anything specific to look for aside from the usual suspects of lifters, rocker arms and rods?
 

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Ouch, that is rough on a rebuild kit. Any other options for the transmissions? T5 or T45 maybe? I know that some fab work would be in order for the shifter and converting from the cable system to the hydraulic.
 

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Ouch, that is rough on a rebuild kit. Any other options for the transmissions? T5 or T45 maybe? I know that some fab work would be in order for the shifter and converting from the cable system to the hydraulic.
Dont even bother, the T5 wont hold up to the 3.8 SC's power for too long and the T45 wont bolt up period.

Find a used M5R2 in working condition .. I have two on the side of my house. :D

Find a replacement supercharger ( 89-93 are a dime a dozen, cheap to come across .. much cheaper than re-building ) .. or upgrade to the 94/95 Supercharger if you have an extra $250-300 laying around.

Check www.sccoa.com .. plenty of information over there.

Also, check for knocking sounds .. could be a harmonic balancer or loose pulley .. or the infamous Rod knock. Also check your motor mounts, make sure your Oil Pan isnt rubbing on the K-member.
 

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Dont even bother, the T5 wont hold up to the 3.8 SC's power for too long and the T45 wont bolt up period.

Find a used M5R2 in working condition .. I have two on the side of my house. :D

Find a replacement supercharger ( 89-93 are a dime a dozen, cheap to come across .. much cheaper than re-building ) .. or upgrade to the 94/95 Supercharger if you have an extra $250-300 laying around.

Check www.sccoa.com .. plenty of information over there.

Also, check for knocking sounds .. could be a harmonic balancer or loose pulley .. or the infamous Rod knock. Also check your motor mounts, make sure your Oil Pan isnt rubbing on the K-member.
T5's were used in 5.0L IROC's, depending on the model, they could make 230HP and 300ftlbs of torque. I would love to go back stock with it. Damn sure makes my life easier, but I am not finding much in the way of parts locally.

The knocking is fast paced, on the upper portion of the motor, doesn't have the extreme THUNK of a rod knock. First entry in the log book that was in the car. "Engine Rebuild. It's ALIVE. 138K miles". It has 150K now, so unless someone made a huge mistake in the lower end, rods just don't seem likely to me. Seems more like they left a rocker nut loose or something.
 

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Engine

You could have a bent pushrod or valve if it is on the upper part of the motor, i have had many super coupes and in most of them though, a rod bearing went out. they can do that very quickly depending on how well it was put together. Pull valve covers off and take a look.
 

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You could have a bent pushrod or valve if it is on the upper part of the motor, i have had many super coupes and in most of them though, a rod bearing went out. they can do that very quickly depending on how well it was put together. Pull valve covers off and take a look.
As soon as I get some free time, I will. Funny cause the last entry of the journal was from February 08 and the mileage was 148K, now 150K. Then I found receipts from December of last year in the car. Obviously it didn't get driven that much in 3 years, someone parked it for some reason.
 

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The T5 would hold up for a while behind a stock 3.8SC motor, but they are nowhere near as strong as the M5R2. Also, the M5R2 has better gear ratios to move these heavy cars, and they are usually pretty cheap to pick up a spare one. My reccomendation as far as the transmission goes is stick with what you have and look for another one in good shape. As the supply of M5R2s dwindle, the T56 swap will become the better option, but for the amount of fab work needed to take a step backwards and put a T5 in there, it is not worth it.
 
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