Can anyone tell me when I change my 350 tranny to 700r4 if I use an 82 crossmember with the 700r4 will it bolt up without any modifications with the 700r4 on the 81 body.

I've already discussed this with Ed, and I have a trans I'm building for him. My theory on this is the x-members are prolly pretty close to the same, but the mount brackets for the '82 are prolly farther back on the frame than the earlier cars, since it would have been easier for GM to move those than to re-engineer a new x-member for that one year only. I have no proof of this...just a theory. I've never had the two x-members side/side for comparison, so I can' say for sure what the differences are, other than the '82 would have a larger area for the speedo gear housing...
I'm not sure either, if using an '82 x-member on an earlier car would work, or how much fabrication might be needed, if any....

Perhaps Dennis(dnv) has pics of the x-members on his car, as he is also swapping for the 700, but he bought his x-member from Bowtie Overdrives(I think)....


btw...as far as the speedo housing size difference, I have determined that I can shorten the 700 tailshaft about an inch, and you can use your original 350 tailhousing, with your original speedo gears, thus eliminating that as a hinderance on these swaps... No guessing as to what speedo gears you need for the 700, as the 350 gears and housing will bolt/slide right on. This also makes it so you don't have to cut the drivingshaft down as far, and you don't have to worry about the larger 700 speedo housing interfering with the x-member....
Adams' Apple2009-05-26 11:10:17

What are the advantages of swaping to the 700R?  Just the better mpg with O/D?  Is it really worth the extra $$?

Besides the better gas milage the 700r4 with the overdrive gear will decrease the cruising rpms on the motor at 70 mph from 2700 to 2000...easier on the motor. I do more highway cruising than town cruising. I am hoping with the lower rpms and a different exhaust system I will also get a quieter more enjoyable ride. I will let you know more when I get it finished.

BTW ya'll...Ed has done some research, and bought a few things for this swap. IF it all works out the way it appears it will, we will b posting some really neat info on how to get this swap done without a major pita, meaning crossmember mods, or buying an aftermarket crossmember...stay tuned!

Sounds Great  I would like to this to my 77 She a driver and with the increased MPG I could drive her more often

Ok tranny is in....here is the scoop....Tranny is from a 1984 camaro (rebuilt by Joel ) so it is fully hydrolic no need to add electric connectors, Bought the shifter convertor from shiftworks, real easy to convert, used the TV made easy cable from Bowtie overdrives again an easy conversion. Now for the part everyone wants to know about...the crossmember is from a 77 used with a caprice tailhousing the mounting slots on the x-member has to be entended one inch and you get a direct boltup. If you put the 3rd longbolt in you have to drill out the holes in the crossmember to get them to fit. Will have the driveshaft cut and balanced next week and should be driving by next weekend.