Perhaps a new V8 for our 1947 Desoto Suburban

[James_Douglas]

In about 8-9 years we will be fully retired ---I hope.  We plan on doing a lot of traveling around the US and Canada.  We will be pulling a vintage trailer of some kind.  We want to use the 1947 long wheelbase Desoto Suburban. 

 

The flathead six can do the job.  However, the point of the traveling is to enjoy.  The problem is that people with modern cars do not have a sense of grace.  As such, they will be very impatient and do stupid things as we slowly accelerate with a flathead six and fluid drive towing a trailer.  The mix of low horsepower and todays cars just would not make the driving fun.

 

It would also be nice to have AC and be able to plug in the electronics without the usual issues with 6VPOS.

 

SO, I am thinking of putting a V8 into the Desoto.  I saw a very nice job of a SBC in a 1947 Plymouth yesterday.  They did not have to cut the firewall or the inner fenders to fit it in.  They used power rack and pinion steering.  I could not tell if they had to make a new front floor board to clear the transmission.

 

What I would like to ask of the people on the forum is the following:

 

Would everyone over the next few months keep an eye out for people that have done V8 conversions on 1946-1948 Chryslers and Desoto's.  If you see one, take any photos you can get of the engine bay and their steering arrangements. If you happen to get a chance to get photos of the underside and the mounts, cross members and the like that would be a plus. 

 

If you get anything, post them to this thread or email them directly to me at JDD@8bells.com.

 

I want to see what others have done and add it to the mix for figuring out what I want to do.

 

Thank you all, James

[JerseyHarold]

I noticed you didn't mention the brake system.  Would you be upgrading that as well?

[pflaming]

Mark Hammond, forum member in Fresno, CA has a Mopar V8 with PS, etc., in his 48 Plymouth. You might contact him. I do not know what size. 

 

Edit: Would like to see pictures of your suburban.

Edited October 21, 2013 by pflaming

[mrwrstory]

I have installed a small block Mopar in my 48 Plymouth with minor modifications to the firewall.  I believe your engine bay would be enough larger that a similar install would not require firewall mods.  You may not wish to go to the extend of modifications that I did but, my build might be helpful reference.  Check 

I'm back  in P15-D24 Forum 
Started by mrwrstory, 11 Jan 2011 

I know much of the info and pics are gone but I'd be happy to send you reference from my picture file.  Post your needs here for response from any on The Forum or shoot me a PM and I will provide what I can.

Good luck.  sounds like a great project and a worthy goal.

Edited October 21, 2013 by mrwrstory

[wayfarer]

If the goal is a uber dependable package then you need to consider the Mopar 4.7 as used in millions of Jeeps, Durangos and Ram1500 trucks. In fact, you should consider buying a Jeep/Durango wreck and you can use a lot of the pieces.

The DeSoto is too nice to use a shiverlay.

[Niel Hoback]

  Amen to that!  There are better combos to use than an old shivvy.

[greg g]

Maybe you could have a conversation with Tim Adams about the 3.5 high output or 3.9 Mopar V6.  Both were over 230 HP are sawed off 318 magnums, Found in Dodge Intrepids and Chrsler Concords, LHS  All rear wheel drive drive trains. 4 speed auto with lockup.  Plus both Dakota and Ram 1500 trucks.  Should fit in without and hammer or torch work.  

[Scruffy49]

Hood open like a modern hood? I'd be runing a Ford V8 for its front mounted distributor. As dependable as the 318/727 in my 69 D100 are, they are getting replaced with an FE (352-428) Ford big block and a C6. I like big block Mopar engines, but the leaned over distributor is almost as big a headache for me as the small block rear mounted unit. And a 360 or 390 with a C6 gets better fuel economy than a 361-440/727 combo, which in turn actually get better fuel economy than a 318/727 in normal use.

 

As far as GM powertrains go, we have a 1985 C10 short/wide that came stock with a 4.3L (262 cubic inch) 4bbl V6, a TH400 3 speed slushomatic, and 2.73 rear gears. It gets better gas mileage (22-26) than the 2.3L (144 cubic inch) fuel injected dual plug 4 banger 5 speed in my 1994 Ranger, which is only getting 19ish mpg right now.

[wayfarer]

... I like big block Mopar engines, but the leaned over distributor is almost as big a headache for me as the small block rear mounted unit.

 

Just how often do you find yourself mucking about with an electronic ignition system...?  And, IMHO, as good as the FE is, it simply doesn't compare to the B-RB in parts availability/prices, range of displacements, or the availability of MH take-outs at rock-bottom-prices. Your results may vary...

[Dave72dt]

If looking at the more modern powertrains with computer controls, pull something from a truck as the tune will already be tow oriented.  With the modern, current engines available many don't have the distributor issue that Scruffy has issues with and there are people who can redo your harness, and reflash the computer to get you set up properly, eliminating what you  don't need.  As has been previously discussed on another thread, check your insurance policies for towing coverage.

[YukonJack]

Well James, I knew it was going to happen as soon as I saw your reference to SBC, that you would get flack from Mopar purists. It's your car, if you want to put a lawn mower motor it in go for it. A guy around here has a 50 Desoto with a 350 in it. He has mounts that run from the radiator support and are connected to 55-57 Chevy mounts attached to the front of the block. It's my understanding Hurst made a mount kit for 46-48 Plymouth and Dodge that was based on this same set up. He has a 350 trans and stock steering also. In the 50s-60s people were putting Cadillac and Oldsmobile engines or Hemis in everything and no one cared.

[greg g]

I have had 3 friends who had 10,11,12 Jeep G Cherokees with the 4.7.  They had transmission troubles that could not be diagnosed/repaired by the dealers.  One traded, one insisted on a swap (temp fix) and the other has his for sale.

[wayfarer]

I have had 3 friends who had 10,11,12 Jeep G Cherokees with the 4.7.  They had transmission troubles that could not be diagnosed/repaired by the dealers.  One traded, one insisted on a swap (temp fix) and the other has his for sale.

...and yet my wife's 2002 Durango has 150K on the clock, runs strong and we have never had a trans issue. Yes, I service the trans very regularly and I expect it to go 200K.

[steveplym]

I've got an sbc with a 350 turbo in my '47 Dodge.  It fits nicely without any firewall modification.  With the fat man front I've got rack and pinion steering and disc brakes.  The car drives just as good as my '04 Dakota and sbc parts are a cheap and easy to find.  I bought the car this way, so I do not have any first hand knowledge of the swap.  I do have friends that have done several '40's mopar street rods and say it is not a hard swap, and there are a lot of parts available to help.  Whether you go 350 or 318 or whatever you decide. 

 

Vintage air is easy to add to this setup and cruise control is just as easy.  Let me know if I can help you with any info James as you venture into this project.

[murfman1967]

The 4.7 is a good engine, but a bad swap choice, as it is a very wide motor and would cause clearance issues with the inner fenders.  A 5.9 Magnum would be a simple swap if you wanted factory EFI.  THe Hemis are getting affordable but wiring is a pain with the Disributorless ignition and MDS.  These are pics of a 50 Chrysler with a 440.  This install was with the stock steering and front suspension.  Generic block hugger headers worked fine.

 

 

 

 

And the car:

[murfman1967]

IMO putting a Ferd or Chubby in a Mopar is sacreligious.  Keep it Mopar!!

 

One other thought that would be a simple swap would be a Jeep 4.0 (I know it was an AMC motor, but in the end it was a Mopar) straight 6 it would fit nicely in the engine compartment that was designed for an inline 6, and offer double the HP of the flathead.  They are known to run 300K miles in Cherokees and are very reliable with simple electronics, and there are literally thousands of them out there in Cherokees, Grand Cherokees, and Wranglers.  Get one from the mid-late 90s and it is an easy swap.  Many Cherokees and Grand Cherokees were 2 WD, and there are 2WD 5 speed ones out there as well.

[Don Coatney]

Why not go with a Mercedes 5 cylinder turbo diesel.

 

http://www.google.com/imgres?imgurl=http://img.gawkerassets.com/img/18axio3gxd7uejpg/ku-medium.jpg&imgrefurl=http://jalopnik.com/385448/&h=281&w=320&sz=99&tbnid=KBa3zivKLyWaNM:&tbnh=96&tbnw=109&zoom=1&usg=__KAHqFlrwrjLjNEdEJXHGeZjRxp4=&docid=2MykIdGbTi_iWM&sa=X&ei=8dhlUpnTBs722QWow4CwDA&ved=0CGwQ9QEwCQ

[GlennCraven]

IMO putting a Ferd or Chubby in a Mopar is sacreligious.  Keep it Mopar!!

 

 

I wouldn't put a Mopar engine in a Ford or a Ford in a Chevy, either. It's just not how I'd prefer to roll. Especially when staying Mopar in a case like this would seem to be just as practical and affordable.

 

But it is true that it's the owner's car and the owner's decision, and ultimately he's the only person who needs to be happy with the results.

[GlennCraven]

 

 

That beast is spectacular!

[murfman1967]

Thanks. It was a project my dad and I built. I bought it for him for Father's Day back in 1993 we got it running with the straight 8 but it was tired and he wanted a little more umph. So it got a 440 with a 518 OD trans, disc brakes all around and a Dana 44 from an International Scout. For a period of time it had a 13.0 to 1 505 stroker in it running on E-85. But the local gas chain that carried E85 filed bankruptcy and Speedway took them over and E 85 was hard to find so a stock 440 went in its place. It was a shame becUse it really MOVED with the 505. He owned it for 18 years, the longest he'd ever owned a car. I sold it for my mom when he passed. It was in the finger lakes area of NY last I knew.

[YukonJack]

IMO putting a Ferd or Chubby in a Mopar is sacreligious.  Keep it Mopar!!

 

One other thought that would be a simple swap would be a Jeep 4.0 (I know it was an AMC motor, but in the end it was a Mopar) straight 6 it would fit nicely in the engine compartment that was designed for an inline 6, and offer double the HP of the flathead.  They are known to run 300K miles in Cherokees and are very reliable with simple electronics, and there are literally thousands of them out there in Cherokees, Grand Cherokees, and Wranglers.  Get one from the mid-late 90s and it is an easy swap.  Many Cherokees and Grand Cherokees were 2 WD, and there are 2WD 5 speed ones out there as well.

I have read that the straight 6 Jeep engine is considerably longer than the flathead.

[Robert Horne]

IMO putting a Ferd or Chubby in a Mopar is sacreligious.  Keep it Mopar!!

 

One other thought that would be a simple swap would be a Jeep 4.0 (I know it was an AMC motor, but in the end it was a Mopar) straight 6 it would fit nicely in the engine compartment that was designed for an inline 6, and offer double the HP of the flathead.  They are known to run 300K miles in Cherokees and are very reliable with simple electronics, and there are literally thousands of them out there in Cherokees, Grand Cherokees, and Wranglers.  Get one from the mid-late 90s and it is an easy swap.  Many Cherokees and Grand Cherokees were 2 WD, and there are 2WD 5 speed ones out there as well.

 

This Jeep XJ 1998, rolled over, I bought for one of my projects, 192HP HO 4.0, 2 wheel drive, automatic, 3.55 rearend.

 

Rolled over, but runs good, makes for a good yard truck, for now.

 

My XJ is pretty fair at pulling small trailers, with wood, brush, etc.

 

I will have to pull something heavy to see how it works.       The XJs weigh about 3000lb...

[Robert Horne]

I have read that the straight 6 Jeep engine is considerably longer than the flathead.

 

This is true.         To compensate, I plan to use an electric pusher fan, and a very good radiator.

 

The Jeep XJs came with a minimum cooling system that needs to changed most of the time anyway.

[De Soto Frank]

If you're looking to get more oomph to compensate for "insensitive modern drivers" ( or whatever other reasons you feel you need more oomph ),  I wouldn't "settle" for marginal gains provided by

slightly larger six (ie: the Jeep 4.0 liter) or small V-8.

 

If you were going with a six, the only one I would consider would be the Ford 300 cid, one of the late incarnations with EFI. They are strong and bullet-proof.   I have no idea how it would fit.

 

 

If this were my project and goals, I would be looking for a late-model Chrysler big-block (440) and suitable tranny and rear-end.

 

The S-11 Suburban is a huge car, on par with the LWB Chrysler Imperial of the same vintage.  It is big and heavy.  Plus you're talking about dragging an Airstream  trailer behind it.

 

You're going to need lots of HP just to get the rig moving, plus whatever reserve necessary to keep-up with modern traffic.

 

Talk to anybody who hauls a fifth-wheel camping trailer or who tows a show car in an enclosed trailer: they're not doing it with small-block engines.  They've  got trucks with either big-block V-8 / V-10 gas engines, or Diesels, and OD trannies (automatic or 5 or 6-speed sticks).

 

Try and tow a big heavy package with a  Chevy 350 or Ford 302 or 351, and they will do it, but they'll be maxxed-out most of the time, and will see shorter service life between rebuilds.

 

 

If you're straying this far a-field from the original flathead Mopar drive-train, you might as well get the most bang for the buck, and have enough power to haul the car, run the A/C, tow the Airstream, AND contend with modern motorists.

 

 

I'm all for staying stock,  but when you're gonna change, might as well do it once and be satisfied with the result.  No sense in trading an insufficient old six for an newer, insufficient V-8.

 

 

My thoughts, so far...

 

 

PS:  My inspection mechanic always talks about his 1939 De Soto that he repowered with a Chrylser 383 and push-button Torquelifte (complete with PB control).  I asked him "how did it fit?"  He says "Great - just had to make some front mount brackets. Kept original steering gear, column, brakes (   ), etc. "

 

 

[vintage6t]

The 4.7 is a good engine, but a bad swap choice, as it is a very wide motor and would cause clearance issues with the inner fenders.  A 5.9 Magnum would be a simple swap if you wanted factory EFI.  THe Hemis are getting affordable but wiring is a pain with the Disributorless ignition and MDS.  These are pics of a 50 Chrysler with a 440.  This install was with the stock steering and front suspension.  Generic block hugger headers worked fine.

 

 

 

 

And the car:

 

I believe the Desoto will be about 5" shorter in the compartment b/c of the difference between the 8 and 6. I'm not 100% positive of this but I'm currently putting a Mopar 383 BB in a 50 Desoto and it does require some firewall modification around the back of the heads. I'm keeping the stock steering so that may be the difference also as the engine sits high and back to clear the center steering.