Hello.. I have a 73 challenger that originally was a 318 car. It is now a 383 car. I had the 383 built and only has about 60 mi on it. well... I was driving it home from the shop and the tranny quit working. it has a 727 tranny. I would assume whomever switched the motors from small to big would have changed the tranny as well. Question is... what is the difference between the two 727's? I have already switched the converter to one with a higher stall rate and changed the flex plate as well. (I did this when i had the motor built.) any other idea's?

 

when they changed the motors, they had to change the trans, cause the bell patterns are different between the two. Did you have the trans rebuilt along w/ the 383? If not therin may lay your problem, if you put a higher stahl converter and a new motor in front of an 30 plus year old trans w/ alot of miles, its not gonna last long.whats the car doing ? moving slow but freereving alot, not moving at all,do you have reverse?does low 1 and 2 work? It could have been a band that snapped.

 

unfortunatly no.. The motor that came with the car was supposed to have been a rebuilt 383 stroker. When I got it running I found out that whomever swapped/built did not balance so.. i started from least expensive fix and then it came to a 5k rebuild. basically the tranny when i first started with the rebuld had a solid shift especially from 1st to 2nd. I took it in to have new springs put in the rear and as i was driving it home the tranny basically gave completely out. it would shift but would "slip' then.. nothing. I coasted into a driveway and shut it off for a minute and then was able to go again but not very well. at one point i heard a lot of "crunching" during a shift.

 

sorry to hear that man, Its unfortunate but true, If you want to build a mope its gonna cost some jing. Id say pull the trans when you get the extra and have the trans rebuilt. then try it again, make sure that when you reinstal the trans, that you have the kickdown lever from carb to trans hooked up or else youll burn the trans up again. I alwys put manual valve bodies in my trans when I rebuilt them, saved messing around w/ the kickdown, and it helped w/ the stahl converter.

 

will do. thanks for your help. that may have been a contributing factor because the kickdown was not intalled before i rebuilt the motor.

 

glad to help. good luck.

 

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