Hot Rod Forum banner

Finding a V8 Chrysler engine and transmission for a"48" Plymouth Business Coupe?

4K views 24 replies 13 participants last post by  BogiesAnnex1 
#1 ·
Finding a V8 Chrysler engine and transmission for a"48" Plymouth Business Coupe?

Can anyone put me on the right track on what would
be a good choice for a Chrys. engine that would
work with the original frame in my "48" Plym.-Coupe?Would like to match an engine with a 4 or
5 spd.manual trans.Any ideas would be greatly
appreciated.Thanks:
 
#2 ·
Before you choose an engine you need to decide what you want the car to be. A cruiser, street/strip hot rod etc. That will guide you on your engine choice.

For a comfortable cruiser a 318 will work just fine. Adequate power and they are very plentiful and cheap.

For a street/strip car I would suggest a 340. Lots of high performance potential and parts available. (Most will also fit the 318)

If you are looking for even more power then a 440 would be the way to go. Again there are lots of them out there and they are about the cheapest big block going.

If you want to go exotic then find yourself an early hemi. One warning here though, they may be relatively cheap to buy but they are not cheap to rebuild and modify. It will cost you about as much to do a stock rebuild on an early hemi as it will to do a performance rebuild on a big block Chevy so keep that in mind.

The hemi cannot be matched when it comes to class though and they are worth every penny you spend on them.

All these motors can be mounted in your frame. You may need to fabricate motor mounts but they aren't that difficult. There may also be some aftermarket universal motor mounts that will work.

Now decide what you want and go for it.
 
#3 ·
A good place to start would be to buy the book,How to Build Chrysler,Plmouth,Dodge/ Hot Rods by Tex Smith. It gives many different aspects on building a Mopar. The bigest problem you will face is the placement of your current steering colum/gearbox. If you use a Fat Man Fabracations rack and pinion set-up and a new colum you can put whatever engine you want into your 48. The frame is plenty beefy to handle anything.Just depends on how much you want to put into the car. Plydo in West Virginia also has a lot of motor mounts etc. to check out. Good luck in whatever you decide to do.
 
#4 ·
I'm in agreement with Centerline totally. There are not many engines that can beat the class and shear performance of a Hemi! ;) You might also want to think about a 360 as they are pretty plentiful as well. A 383 might be an option as well. Like Centerline said though, you really should know what you want to use the ride for.
 
#5 ·
There just aint no comparison to the HEMI(even the biggest GM and FORD top fuelers use'm), but if your on a budget then a more common(and affordable)engine is what you want. 340's were great engines from 68-74, but the 360 is a much better choice for a lotta reasons. 318's are good basic engines. however, if you want to build somethin then I would suggest you start with a 400. MOPAR has a wide range of good blocks to choose from. If you still need more help then get a MOPAR PERFORMANCE catolog and let your imagination run. 318,360,and400 are readily available at most wrecking yards(cheap). Also, lotsa good ideas in any MOPAR based perfomance mag. Good Luck
 
#7 · (Edited)
I know what I'd do with it. I'd shop around for a late model Dakota truck with a V8-5spd that has been disabled for one reason or another. I'd buy the whole truck and disassemble it piece by piece, selling off the sheet metal and glass as I went. I'd cut the Plymouth frame clips off and weld front and rear clips from the Dakota onto the Plymouth stubs. Presto. Late model motor, trans, rear, steering and brakes all complete. EFI, Dakota wiring, computer and the whole mess. Done.
 
#9 ·
ParatrooperAlex said:
What about using a dodge v6 with EFI? how well would it fit?

also, if i were to use a 318, what is a good manual tranny w/ overdrive to use?
Just my opinion but a V6 would be boring in this car. 318s with 4 speed OD trannys were fairly common in Aspens, Volares and trucks. Put a set of 340 heads, cam, intake and etc. on a 318 and you won't know that it ain't a 340. The aforementioned 360 is also a good choice. Once again, 340 heads are a bolt-on and will wake it up nicely. It can also be made to run quite well though with the right 360 heads. The 340 stuff is getting rarer and costly. BTW, the factory 4 barrel intake that was used on 340s is an exceptional dual-plane intake. It was many, many years before any after market dual planes were made that were really any improvement. You can also still buy brand new the factory 340 3 deuce induction set-up that was used on AAR Cudas and T/A Challengers. Both power-wise and for too cool looks, this is an excellent set-up for any small block Mopar, from a built 273 or 318, up to the 360.
If you want some killer torque, stroke a 340..... :cool:
Interesting side note, the 273, 318 and 340 all used the exact same stroke. The early 318 engines (not really small blocks per se) known as "polys" had a forged crank from the factory. Racers used to scarf these up to use the cranks in built 340s, it's a bolt-in. Also, 273s had adjustable rocker arms from the factory. 318s, 360s and most 340s did not. The 273 rockers are usable in these engines.
 
#12 ·
Chrysler engine for 48 Plymouth

If you DONT want to subframe, slice,dice, hack or maim, and DONT want any steering interference, look for a 55 Plymouth or later. It was a small V-8. about 260 ci if memory serves me right. Used one with a 55 3 speed in a 48 2 door many years ago. Would love to do another,it literally smoked every one in the area, fine combination.
 
#13 ·
Have any of you guys bothered to notice that this is a 5 YEAR OLD THREAD????? I'm sure the guy has an engine by now.
 
#18 ·
Chevrolet4x4s said:
lets atleast get a little useout of this thread can the 318 poly crank be used in a 360 block? and the 360 crank in the poly?
Shane
I seriously doubt it. They are entirely different engine families. The 318 poly is more related to the early hemis than the "A" engines.
 
#19 ·
Centerline said:
I seriously doubt it. They are entirely different engine families. The 318 poly is more related to the early hemis than the "A" engines.
So it would seem. However, the 318 poly crank is a bolt-in for 340s and was used extensively in them back when I drag raced Mopars 25+ years ago. This is because it was a forged piece. I'm not sure if journal diameters for 360s are the same as 340s or not, I never really fooled with any 360s. If it did fit, it'd be a de-stroke for the 360 though.
 
#20 · (Edited)
Notorious said:
So it would seem. However, the 318 poly crank is a bolt-in for 340s and was used extensively in them back when I drag raced Mopars 25+ years ago. This is because it was a forged piece. I'm not sure if journal diameters for 360s are the same as 340s or not, I never really fooled with any 360s. If it did fit, it'd be a de-stroke for the 360 though.
I was thinking of the earlier polys rather than the "A" poly. After checking my books you're right. It is a bolt in for the 340 (273 as well) but the main journals for the 360 are .125 larger so unless someone wanted to weld and then grind the crank it won't go in a 360 easily or inexpensively.
 
#22 ·
Chevrolet4x4s said:
Just curious since my ol dodge has a 318 poly.......will early hemi heads fit?
Shane
Nope. Your poly is related to the "A" engines rather than the early hemis. It would have to be a 301, 331, or 354 poly for the early hemi heads to fit.
 
#24 ·
Ooh different series of poly engines (Chevies are so darn easy lol) Also is there a production 5 speed from that will bolt to the b/rb engines....Kind of like to build a Mopar powered rod at sometime maybe a 440(70 Challenger 440 rt 4 speed made up my mind that Iwill own a 440 someday :D ) :thumbup:
Shane
 
#25 ·
oldbogie said:
Yes the early polysphere can be retrofitted to early hemi heads, I just can't remember in the 3 or 4 different versions of the early hemi which ones fit, I'll crawl through my ancient notes to night and get back to you.

Bogie
My BF thinking 315 hemi/spitfire block not 318 A block. The correct answer is no, Centerline is dead on.

Even converting a spitfire to a hemi is a big job. Not that I'm against it, it's just an effort.

Bogie
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top