Thread: 318 in a 49 plymouth

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Does anyone know if a 318 will work with the stock 3 in a tree tranny in my 49 plymouth? I know I will need to buy or make an adapter for this, That is not a problem, I also know from another post that the steering will be in the way, so thats not a problem either, I can find a way around that once the engine is in. The problem I need to know is will the 3 speed tranny be able to handle the 318 as I kind of want to keep the 3 in a tree, rather than a straight "H" or an automatic floor shifter.

If it won't is there a newer (more powerful than the original 225) that will work? Slant 6 for example. I got on in a mid 70s valare that I can get the whole car for 2 cases of beer.

the 318 might be a little too tough for the tranny.... and yeah you'll need a transadapter kit, but you can also take that tranny to a shop and have it built to handle more power.... the thing i would worry most about is the rearend, because it was definately not made for that kind of torque....of course thats what an aftermarket 9" is for.... i wish i knew more but the only old mopar car i had was a 48 dodge business coupe with a 318 and an auto... the guy i had bought it from had already done everything to it... and i only had it for 2 weeks before my mom made me get rid of it....

The rear end is being changed out to a chevy 10bolt. Its the only one I have found that is the right back to back, at least so far, am going to check the volare to see that one.
But how much work will the tranny need? Would it be feasible to rebuild it or find a newer 3 speed that can work with the 3 in a tree?

while it could probably be made to work, I think you might be better off using a latter model 3 speed and bellhousing made to fit behind the 318 (trucks Dusters and Darts are good donner vehicles).

The 3 speeds are not in high demand so the cost is generally pretty reasonable.

I kind of think the fabrication modifying shift rods/clutch linkage /crossmember would be easier and cheaper than trying to adapt the original tranny to the 318. You would also have the peace of mind in knowing the tranny would hold up behind the 318.

Those trannys aren't very strong, though we did run them behind 354 Chryslers (just not for long!) The tree shifter will not work on any other style trans, due to the push-pull selector setup found only on those old Mopars.
A slant six and four-over would be great.

".......The tree shifter will not work on any other style trans, due to the push-pull selector setup found only on those old Mopars...."

Just had a 49 Chrysler in a friends shop, (3spd column shift with OD). From the looks of it it's just like any other 3 spd column shift. All that it would take to make it work with any ither 3 spd manual is the correct levers on the trans and adjusting the shift rods.

even if the shifter will not work, the colum dosn't have any internal parts ( shifter linkage, turn signal or anything like that, I don't think ( my '51 chevy dosn't, going by that ) so the shifter could be removed and replaced with the unit from an old Chevy or Ford from the approxamate same years, and just fit that onto the mopar colum with the right amount of fab work.

Ok I found this car for sale, its a 4 door. 70' dodge dart with an inline 225 slant six, with 110,000 miles that runs great. The guy wants 500 for it. Would this be a good deal for a donor car for the 49? And does anyone know what the backspace on the rearend would be for this car? ITs all original

Tim, not to be a smart***, but let's get some terminology correct first. Backspace refers to wheels. If you lay a wheel face down on the garage floor and lay a 2 x 4 across the rim on the backside, then measure from the bottom of the 2 x 4 to the mounting surface on the backside of the wheel, that is the backspacing of the wheel.

What you're looking for is differential width or rearend width or rearend housing width, either from the wheel mounting surface on the axle or the wheel mounting surface on the drum or from the backing plate. It should be a simple matter to measure the width of the housing on the '49 and on the '70. Compare them and see if they are close.

I would think this would be a natural for a donor car. I'd take everything off it including the electrics.

The rear in the '70 is a 7 1/4" ring gear, 2.76:1 standard ratio.

Tech, I knew it was the wrong term, what I meant was space between backing plate to backing place plate of the drums.

Hey guys. Just reading up on 318 projects. Well here's what I'm gonna do...1949 Fargo (Dodge) 1/2 ton, 318 PolyHemi, 9 inch Ford rear end, Torque-flite auto trans (maybe I haven't figured out what trans I want yet). Mustang II equiv. front suspension, rack and pinion steering, Air Ride, Wood floor box, and just the right amount of chrome with deep Royal Blue paint. I originally thought of building this truck chopped and dropped, but I think I want a real truck instead, not something I can't take out a use... get it off the ground just a little, maybe a 2 inch lift (from factory) with slightly oversided tires. You know get that mean look! Anyways that's what I'm planning on doing when I get my other projects out of the shop.

MikeP...The shifter works different. One lever shifts low/reverse, then you move the second lever and the first one then shifts second/high. The vertical movement of the column shifter moves the second lever. Wierd.
Joker51...The '70 slant six and drive train would be great, rear end and all.