Transmission extension housing

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Aussiemopars

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I'm trying to fit a 383 and 727 tranny into the Cuda convertible and I've been having a few problems with the fitting. I suspect the transmission extension housing maybe shorter than a standard 727. Are there different lenghts between the trans mount and where the extension housing bolts to the main body of the transmission?
 
Not sure on the Aussie versions but over here all car 727's are the same. Their also the same as 1/2 ton 2wd trucks. Only HD trucks and motorhomes and 4wd are different.
 
It's a 69 Cuda convertible. I just pulled out a slightly tired 360 & 904. I can also confirm that all the 727's downunder are all the same dimensions as well. I was thinking that because the motor/gearbox didn't line up on the mounts that the gearbox was maybe different. I managed to get a long bar in between the motor and firewall and wedged the motor forward enough for it to sit on the mounts.
 
What type of motor mounts kit or big block k member? to change over fom s/b to b/b.
 
Aussiemopars said:
It's a 69 Cuda convertible. I just pulled out a slightly tired 360 & 904. I can also confirm that all the 727's downunder are all the same dimensions as well. I was thinking that because the motor/gearbox didn't line up on the mounts that the gearbox was maybe different. I managed to get a long bar in between the motor and firewall and wedged the motor forward enough for it to sit on the mounts.
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How far off was it? Something doesn't sound right or it should have dropped right into the mounts. As Walt asked, what mounts are you using? I assume you either swapped the K member to a big block K or are using someone's conversion motor mounts?
 
fishy68 said:
How far off was it? Something doesn't sound right or it should have dropped right into the mounts. As Walt asked, what mounts are you using? I assume you either swapped the K member to a big block K or are using someone's conversion motor mounts?
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It was off by about an inch i.e. it needed to come forward about an inch. I'm using the Schumacher mounts.
It also looked like a Chevy guy did the conversion from /6 to SB because the slot holes were all chewed up on the k frame (it had to be a chevy guy, right?)
 
Aussiemopars said:
It was off by about an inch i.e. it needed to come forward about an inch. I'm using the Schumacher mounts.
It also looked like a Chevy guy did the conversion from /6 to SB because the slot holes were all chewed up on the k frame (it had to be a chevy guy, right?)
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An inch is way too far to have to pry something to get it in. Something is wrong there. You should never have to pry it that far. I consider anything over 1/8" off too much so I'd never run it like yours. Are you sure you have the trans. mount installed correctly on the extension housing and the crossmember bolted in the right direction? On the older ones you can bolt the trans. mount up backwards and install the crossmember backwards and of course that creates problems. You might want to check them. I wonder why the motor mount slots were chewed up? Maybe he had the trans. mount and crossmember off to start things and did that to make it fit? Just a thought.
 
fishy68 said:
An inch is way too far to have to pry something to get it in. Something is wrong there. You should never have to pry it that far. I consider anything over 1/8" off too much so I'd never run it like yours. Are you sure you have the trans. mount installed correctly on the extension housing and the crossmember bolted in the right direction? On the older ones you can bolt the trans. mount up backwards and install the crossmember backwards and of course that creates problems. You might want to check them. I wonder why the motor mount slots were chewed up? Maybe he had the trans. mount and crossmember off to start things and did that to make it fit? Just a thought.
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The motor and gearbox were out of an aussie c body (Dodge Pheonix) so I was thinking maybe the trans was a different lenght extension housing.
The other thing is that I think the motor is a friday 13th motor i.e. 12*13*68, which probably doesn't help.
The trans X member looks like it will only go on one way (tried that option) and the rubber mount on the gearbox looks like it can go on either way but with no difference.

*Update*
I just had it all in and then went to lift the motor up on one side to fit the Schumacher header and now it won't go back
 
Aussiemopars said:
The motor and gearbox were out of an aussie c body (Dodge Pheonix) so I was thinking maybe the trans was a different lenght extension housing.
The other thing is that I think the motor is a friday 13th motor i.e. 12*13*68, which probably doesn't help.
The trans X member looks like it will only go on one way (tried that option) and the rubber mount on the gearbox looks like it can go on either way but with no difference.

*Update*
I just had it all in and then went to lift the motor up on one side to fit the Schumacher header and now it won't go back
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Again I don't know if they changed things down under but here in the US there is only 1 length big block 727 trans. no matter what body style (a, b, c, d, or e) it came out of. Same for small block tranny's. Since you said you took a 360 (small block) out and are putting in a big block if the trans. crossmember could be different? That's the only thing I can think of right now. And as for the Fri. the 13th thing I know some people put stock into that but I can't imagine a block cast so far off like your describing and the factory using it. I personally put no stock whatsoever in the Fri 13th hocus pocus but that's JMHO.

You might do some asking around to see if the crossmember could be different. Maybe in the big block forum.
 
There doesn't seem to be anything unusual about the X member, it all looks straight forward i.e. no doglegs or anything. It looks similar to the B body one.
 
Aussiemopars said:
There doesn't seem to be anything unusual about the X member, it all looks straight forward i.e. no doglegs or anything. It looks similar to the B body one.
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Ok. I wouldn't think it'd be unusual. Just maybe offset a little. It was just a thought as there obviously has to be something drastically wrong.

Does the engine set to far forward or back?
 
Aussiemopars said:
Engine sits to far back
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Hum... Which side of the engine tabs do you have the motor mount brackets bolted onto? On a sb their supposed to bolt onto the back side of the tabs but they'll bolt onto either the front or back side and if you put them on the front side it sets the engine too far back. I don't know if it's possible on a BB but it's something else to check.
 
Aussiemopars said:
It was off by about an inch i.e. it needed to come forward about an inch. I'm using the Schumacher mounts.
It also looked like a Chevy guy did the conversion from /6 to SB because the slot holes were all chewed up on the k frame (it had to be a chevy guy, right?)
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I went back thru and re read this. This car was originally a slant 6 car? The perch on the passenger side of the K frame appears to verify that by what I can see of it. Also looking at the pictures of the mounts that you posted by looking at the mounts it looks like everything is properly orientated according to Schumachers directions. The question I have for you (and not being an ahole) is the Slant 6 K frame still in the car? The bracket on the passenger side that attaches to the engine appears to be a SB to BB conversion. Also the thickness of the isolators looks to be for the SB to BB kit, the Slant 6 to BB rubber isolators are thicker. If this kit was ordered for a SB to BB conversion and the car has the slant 6 K frame it won't work. Check this link to Schmachers site and look at the differences. http://www.engine-swaps.com/Pages/ProductsYear/67.72aBody.html Hope this helps.
 
Dubob does he have the engine brackets installed on the correct side of the block mounting tabs? I know on a SB they'll bolt up either in front or on the back of the tabs but on the back is correct. I can see in his pics he has them bolted to the back side of the tabs which is probably right but if it's not and their supposed to be on the front side that'd possibly put them in alignment. What do you think? I'd guess it's either that or what you said about maybe their the wrong brackets for his K-frame.
 
Fishy68 The best I can tell the brackets are installed properly. Also the picture of the K frame it doesnt look like the drivers side perch has been notched to clear the oil pump .
 
The photo was taken before the notch was done, but is done now. I manged to get the motor to sit in properly now but not without using the iron bar to wedge it forward.
 
Aussiemopars said:
I think next time I will be doing the procedure as suggested in the other thread:
http://www.forabodiesonly.com/mopar/showthread.php?t=186723
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I don't think it'd make any difference if things don't line up, like in your case. You may have got it forced into place with a big prybar but that's certainly not the way to do it right. Don't mean to sound hateful or anything so please don't take it that way but that's the jest of it. You need to figure out why it doesn't line up or it's an extremely high chance your going to have problems down the road. I know I haven't been much help since I'm not a big block guy but someone must know the answer. Maybe a call to Schumaker's telling them of your problem would be in order?
 
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