Helping out a friend!

[67cuda360]

Hi,
I'm looking for some information.
A good friend of mine is looking into buying a 70 duster with a /6, i was wondering what it would take if he wanted to install a v8 at a later point.

The ad says it already sits on a V8 K-Frame so that is a great start. On the images he was sent it looks like it has 7.25 rear axle, if he wanted to upgrade to a 8.25 is this a simple swap or are we talking shortening driveshafts and moving spring perches?

Also, what tranny would most likely be in a /6 (it is an automatic), and would the tranny need to be swapped to fit a v8 (most likely 360), any other things that we should keep in mind?

Any info would help, if he gets it we'll have another FABO member on our hands LOL

 

[cosgig]

Well, if the car has a V8 K-frame in it already, all he would need to swap the motor in would be the correct V8 motor mounts. Even if it had the original slant 6 K, a V8 swap is as easy as a call to Schumacher for the correct conversion mounts, about $160.00. He may want to check the size of the torsion bars to make sure that they are V8, and if not they should be replaced with heavier duty V8 bars. As for the slant 6 trans, that will have to go, it's for a slant motor only. Either a 904 or 727SB trans is needed, and relatively easy to find and rebuild. As for the rearend, an 8 1/4" is a bolt in to the perches, but the driveshaft would need to be shortened a bit. Now, an 8 1/4 is large bolt pattern and a 70 Duster is small bolt pattern, so either you need 2 spares, one LBP and one SBP, or the front brakes could be changed out to the 73 and later style with the LBP, or he could find an 8 3/4 A body rearend, which would be SBP.

All in all, this swap is Mopar 101, it is done all the time and could be easily accomplished with readily available parts. Like the wise man said..."all it takes is money"!!! Geof

 

['64 Cuda]

Not sure why a 6 would be sitting on a V8 K frame. Even if the car still has a 6 cylinder K frame a set of conversion mounts is only about $160 or so from Schumacher Creative Services. The trans is going to most likely be a 904 but the V8 has a different bolt pattern at the bell housing so a swap will require a different transmission. If the rear axle needs upgraded you can bolt in an axle from another A body without moving the spring perches. You would need the shock mounting plates & U bolts. The drive shaft will have to be shortened if the rear is changed. A V8 swap would probably need a radiator change as well. A lot of people on here seem to be having good luck with relatively cheap aluminum ones sold on eBay.

Dang cosgig, I need to type faster!!! And I forgot to mention the torsion bars. And a 70 Duster is a good looking car.

 

[67cuda360]

Thanks for the responses, lots of great info. I'm not sure why the /6 is already sitting on a v8 K-frame if they could have just swapped the motor mounts. My friend wants to go up this coming weekend to go have a look at it. Do you guys have any clues on how to identify if the torsion bars are heavy duty or not?

 

[cudamark]

The numbers on the end of the torsion bars can be decoded. The factory made 5 different bars for A-bodies. For a '70, there were only 3. 888/889 are the weakest, 890/891 are next stiffest and 892/893 are the stiffest. If they're not any of these numbers, post the ones it has and we'll find out what they've installed. If the slant 6 is in the car and it has a V8 K-member, it must have some sort of modified mounts now.