383 motor swap

[Chris mathiesen]

I have a 1946 plymouth club coupe. I was thinking about swapping the flathead six for a 383 out of a 1966 dodge polara. I know I will have to swap out the rear end as well. I am not very experienced at this kind of thing. Does anyone know if the rear end from the 1966 dodge polara would work for my 1946 club coupe?

[Lumpy]

Hi,

 

Hey, no offense, but if you are not experienced in that sort of thing, don't do it. It comes under the heading of "it can be done", "it has been done", and "anything can be done". You could probably swap in any rear end if you wanted to bad enough. It certainly is not going to bolt-in. You would really be better off finding a car that has already had the swap done. Finance it by selling the Coupe. I'm not against giving an old car some "pazazz", or doing some mods, but at least preserve it as a flathead, or sell it to someone who will.

 

There's lots of hop-up stuff you can do to the flathead six.

 

Everyone that runs a flat six are quite happy with them. Those wanting to swap in modern engines are almost always those who have not driven the car for any length of time with a good running flathead six...usually starting off with a car where the engine needs a rebuild, or there is no engine.

 

A 1966 Dodge Polara would be a great place for a 383. Can you fix up that car? Or maybe find a Dart or Duster to hot rod.

 

I have a 1948 Dodge with a low mileage, great running 230 flathead six, shaved head and dual carbs, and no way would I want a V8 or other engine in it. It is not a stocker or resto by any means. I know what power is, I have a hot 360 Dodge Dart, and I have motorcycles. I'm not saying there's not a place to put a 383...it's just that a '46 Coupe either is not the place, or you'll be so swamped in time and money to do it, you'll have to change more than the rear end to cope with the big block V8...it will really be a major undertaking.

 

Well, that absolutely does not answer your question! Sorry about that. And thank you for not asking about swapping in a small block Chevy. !!!

 

k.

[james curl]

If you have no experience swapping out engines, transmissions, and rear ends you need to find someone who is experienced in doing the fabrication required to do so to do it for you.  This is not for the faint of heart as it is a major undertaking.  It will involve all of the systems of the car to be modified before you are through.   You will also need a shop with specialized tools to accomplish the swap.  If you have a specialty shop do the swap for you get their best estimate of cost and time required then up it by at least 30%.  Good luck in which ever direction you take.

[Eneto-55]

Welcome to the forum (I didn't see your earlier post back in May until now).  Where abouts in California are you?  Are you by any chance from around Fresno, Shafter, or Dinuba?  (I am from Oklahoma, now living in Ohio, but was born in Fresno while my Dad was at Fresno Pacific Bible Institute.)

 

I had a 62 Chrysler with that same block as you're talking about, although it was the 361.  That's a pretty big engine to stuff into the space designed for an in-line six.  I don't know about the comparative weights of the two engines, but the steering sector is one of the things the guys are talking about having to change.  I have also not done that type of engine swap (my 46 has a 55 model flathead in it), but it sounds really major to me as well. 

 

Neto

Edited June 30, 2014 by Eneto-55

[50 coupe]

Just because the guy hasn't done it before doesn't mean he isn't capable of doing it. cmathiesen, there is lots of info on this site about engine swaps and rear-end swaps. Search and read, then you can determine if these are things you want to or can tackle. 

[martybose]

Aside from the steering box, which is a problem for any V-8 in our cars, the biggest decision is how high to mount the motor.  If you mount it high there are no problems with the oil pan, etc., but you will do a lot of firewall/floor work for the transmission and driveshaft clearance.  If you mount it lower there will be less floor work, but much more work in the oil pan/oil pump area.

 

Good luck if you go for it.

 

Marty

 

PS - no matter what route you go you will be making custom motor mounts and transmission crossmembers, not to mention a driveshaft and doing something for the emergency brake, along with probably putting in a different rearend (because the stock one is geared way lower than you want with a V-8).

Edited June 30, 2014 by martybose

[wayfarer]

I'll my 2¢.... And none of the following is meant to discourage you, only give you a heads up. A v-8 swap is a mighty nice thing to have but it is never going to simple.

 

Any of the Mopar v-8 engines will provide plenty of performance in your car. As mentioned, getting to the first drive will take a fair bit of money (even doing it yourself) as well as more time than you'll first think logical/reasonable. Yes, having a shop do the work will speed up the time frame as well as the spending.

Cheap-Fast-Good. Pick any two.

There is adequate room in the engine bay but expect to massage the inner fender panels. The engine will be offset to the passenger side 2", you may need an oil pan from a truck/van, the electrical system will need to be upgraded to 12 volt... Although the front suspension is adequate, you should plan on disc brakes to go along with the later rear axle, and with that you might want to upgrade to a dual master cylinder. Throttle linkage, shift linkage, e-brake operator, trans mount/crossmember, engine mounts and a host of other parts will be custom fab. And the list goes on.........

 

There are examples of similar swaps if you search around. Start with this one: http://p15-d24.com/topic/22985-im-back/

[HughForrest]

As mentioned: Lots of work, but do-able.

 

Pictured is my "38383" ie. 383 in my '38 Chrysler.

 

Pics from the installation- car has been on the road & running fine for several years now. I'm located in Santa Cruz, Ca if you find yourself in the area and want to have a look...

 

 

[martybose]

Hugh's is a good example of a low mount 383.  Minimal firewall work, firewall-mounted power brake master cylinder, not sure but it looks like it must have a Cavalier rack steering setup, and I'd forgotten all about needing to clearance the front crossmember for the crankshaft damper.  Looks like the right side shorty header is modified as well.  A LOT of detail work to do it right.

 

Marty

[Eneto-55]

 not to mention a driveshaft and doing something for the emergency brake, along with probably putting in a different rearend (because the stock one is geared way lower than you want with a V-8).

 

The engine is from a 66 Polara, right?  When did MoPar quit putting the emergency brake on the trannie?  (I know my 62 Newport had it there, although it was an internal drum instead of the external type used on the older models like the P15s.)

[Daliant.]

The rear end from the polara should be just right width wise, it's a little wider than the stocker by about 3/4" on each side, you'll probably have to weld new perches on or move the ones that are on it. As far as the engine swap is concerned it's all a matter of how much of the stock stuff you want to keep, the steering box will be the biggest obstacle it will want to occupy the same space as the driver side exhaust manifold, swapping to a rack and pinion will free up a lot of space in that area. On a big block engine the oil filter will want to be in the same space as the crossmember. Next will be the radiator and firewall, you can only move the radiator so far forward so the firewall will probably need to be massaged a little. there should be plenty of room in the tunnel as long as you don't mount the engine too high or too far back. None of these would be considered deal breakers in my opinion but it's going to take some fab work to put a big block in one of these cars. Disk brakes should be pretty high on the to do list if you go through with the swap.

[Lumpy]

My '64 New Yorker does not have the tranny emergency brake, and I parted out a '63 Newport that didn't have it either.

 

k.

[Eneto-55]

My '64 New Yorker does not have the tranny emergency brake, and I parted out a '63 Newport that didn't have it either.

 

k.

So then 62 must have been the last year.

[Tim Keith]

I like to see the excellent low deck 383 put to good use, its almost been forgotten as most go for cubic inches.   But as for me, inline is just fine.

[james curl]

My post was not to discourage him from trying, but to give him some idea of the time, thought and skills needed to accomplish the conversion from a stock car to a street rod.  It is more involved than just dropping parts in and go,  I know a few professional builder who build cars for themselves and customers.  I see the amount of time spent just to make parts that are supposed to fit, fit.  Check out some of the build threads on this site to see how much time and effort it took to accomplish the build.

[Lumpy]

My post was to discourage, (!!!!)  but I had my say, did my duty, and wish him luck if he decides to do this. Also, I thank the stars that we are talking 383 and not a you-know-what small block, LS6 (whatever that is) or whatever.

 

But I will say that a 46 Coupe does seem like a car that some effort should be made to preserve, (and again I am not a resto-fanatic) especially drive-train wise. Shave the head, dual carbs, lower the front, disc brakes (I personally don't need them) then go for it! Those things can all be easily reversed years down the road.

 

Since they don't make the 383 anymore, it's not like it will go to waste...put it up for sale and someone will want it. What does scares me is the "little experience" thing. I think that 98.3% of the time, that leads to a car that's taken apart, hacked up a bit, and that's the end of it...never to run again. Really, to get that done in a reasonable amount of time, one would need a lot of money, a lot of motivation, and a lot of fabrication skills and knowledge...not to mention a lot of weekends and time after work. Also lots of garage space, and a well equipped shop.   

 

One thing not asked of the original poster, which has a lot to do with it, is: "what condition is the car in now"?? If it's a total wreck, maybe the 383 idea is not so bad. If it's in reasonably good shape, then I think a rebuilt six with some wow-goodies, and some cosmetic work is truly the way to go. It could also be a money-maker, do that, flip it, and use the money to finance a 383 Dart or Duster (also a headache to plant a big block into) or 1960's Dodge pickup, or something like that. Maybe a late to mid-1950's car. ??

 

So, just a few extra thoughts, ideas.

 

k.

[james curl]

I have a friend who just bought a all steel 34 Ford five window coupe that has been all apart for a number of years.  He has reassembled more than a few vehicles that some one started like they were on fire only to have the flame die from lack of fuel.  It will probably take him close to a year and a half to have a running driving, painted and upholstered non fendered high boy hot rod.  It will be non fendered because the previous owner decided that he did not need them and sold them at a swap meet along with the running boards and mounting hardware.  New fenders run around $1200.00 each for the fronts and $500.00 each for rears, hence no fenders on this car.  He does this for a living so he has to make his labor plus parts back when he sells the car.  The reason for new fenders is they are reasonably straight and smooth as received, not needing hours and hours of dinging and filing to make smooth. With these types of fenders you just cannot trowel on the bondo to hide the dents.