Customs Advice wanted

Im new here and I just purchased my first 1947 plymouth special deluxe. My is question is
if I place a mopar 6 225 and 904 transmission which I acquired from a 1965 dodge dart 270 , what rear end will I need to complete the set up. Any advice as to the complications or revisions that I may need would welcomed.

Thanks
agman

John from Central Pennsylvania

 

Welcome here. I had a slant six in my '47 Plymouth and it fits in pretty good but you need a slight notch in the firewall for the head. I used a 9" Ford rear end from a'61 Mercury. Fits good and the spring saddles are even in the right place. A rear end from a Dakota works out good too. The original rear end would hold up but you won't have an emergency brake.

Sent from my SM-T350 using The H.A.M.B. mobile app

 

Kinda depends on your driving. The 225 has a lot of torque for its size, so if you drive a lot at high speed a 3 to 1 rear end would be good. But if you want more take off speed or just drive slower, a 3.5 or 3.7 to one might be better.




Bones

 

Get the rear Axle out of the Dart and use it. I would think that gear ratio couldn't get any better.

 

Measure first, though, as the Dart rear might be too narrow. And notice the wheel bolt pattern is different.

 

The Dart rear end is probably a 7 and 1/4 inch in which case it is one of the weakest ever made and also would have a 5 on 4 inch bolt pattern which there are very few wheels for that pattern.

 

Ford ranger or explorer 8.8 5x4.5 bolt pattern a little narrower than stock .

 

A 225 won't bust a 7 1/4 rear............but the A body rear is too narrow anyway, you are looking for B body or jeep suv or ford exploder 8.8 they all fit fine. If you move the rad forward of the support you will not need to touch the firewall at all.
https://www.cascadepacificplymouth.org/510westphalswap.html

 

Jeep Cherokee ‘91 thru ‘01, is a MOPAR 8.25” which is widely used in various configurations, but the Cherokee has the best combination of width, wheel bolt pattern etc., for your purposes. Six cylinder/automatic Cherokees has 3.55 gears, six cylinder manual are 3.07.

The Ford Explorer rear axle is popular because it is plentiful, strong and cheap. But it is also heavier and a bit of overkill for your application. A good alternative to that is a Ranger pickup from about ‘92 thru about mid-2000’s. Look for an 8.8”with the 10” brakes, some had only 9”.

Ray

 

Try www.p15-d24.com for more info

 

Is there a usable engine and transmission in this car or is that stuff gone?
In my opinion putting a slant 6 in one of these cars isn't much of an "upgrade" for the amount of work required, but if that's what you have to work with then it is what it is.