Engine Conversion

[MoparJigsaw]

Happy "Mopar" Day to all.

I have been blessed with a 1947 Dodge WD21 Flatbed that I am very eager to start having fun restoring. This beauty however has not run in 30 years but just makes it more of a challenge and increased my curiosity. I wonder if anyone has experience with this same truck with a 230 ci flathead 6 and has successfully done an engine conversion on it. What size engine(s) have been installed and how much and what type of modifications were needed during the process. I have all intensions of restoring this flathead but I always like to be aware of other possibilities. I have done engine conversions in the past and know quite well of the issues that can arise but I loved the experiences and will always cherish what I have learned in the process. I appreciate any  suggestions based on these type of experiences. Thanx.

R/

M/J

 

[wayfarer]

Tight engine compartment. I looked under the hood of the truck in my avatar and, did I mention that it looked tight...at least to my eyes.

I also know that many swap have been done and, long ago, saw pics of an EarlyHemi install, so you do have options.

The real question is what do your long range plans include?

[Plymouthy Adams]

ah, they not that tight, I put a 440 into a even more narrow and pointed hood of a 1941 military 1/2 ton....if you got the room time skills tools etc...pick your poison and let the big dog loose

[Radarsonwheels]

I put a low deck big block in mine and ‘Farmer’ did too except mine is set about 8” into the firewall which is all hand made along with the floor etc. If you do the easier job of sinking a radiator farther forward into the grill area a smallblock should fit really nicely with minimal work to the firewall. A corvette style small diameter dual diaphragm swinging power brake pedal with brackets can be had on ebay for less than $150 and the gas pedal is easily swapped for a cable style pedal.

 

I used a lot of dodge dakota chassis for my ingredients too which made a lot of work but now drives like a modern truck.

 

So it’s not just motor mounts and go no matter how you do it plus don’t forget the old brakes & chassis were barely good enough for flathead power. If your brakes and steering are tight and you are good with metal there’s nothing stopping you from rumbling around with v8 power. 

 

I did really love the 230 in mine though. After some reliablity upgrades it was a sweet fun reliable driver- it just didn’t steer well, stop well, and had rotten body mounts... 

 

Ok so I’m rambling but I have a million page build thread on here if you want to check it out. Bisquick has a less radical but much cleaner v8 gen1 hemi swap, and there are a bunch of beautiful factory, better than factory, and off the wall artistic restorations documented on here- lotsa good reading and talent.

[Plymouthy Adams]

the big block is not as long as the small block....in many aspects the small block is longer or taller....it is basically only the width of the RB in and where the exhaust logs will run that is of concern...keep in mind the A engines are the only ones with internal oil pump...

[Jomani]

Welcome to the forum - what area of the world are you in? Don’t forget to post some pictures.

 

The biggest hurdle you will run into is the steering. If you want to preserve the original  steering column, any v8 conversion will be a challenge. I have the same exact truck (aka Cabbage Hauler) that now has a 360 with 727 trans sitting in it (still a work in progress). After playing with engine placement for a couple of weeks, I ended up with a location that will work but will require a very custom set of headers (my next project). As was previously mentioned, an engine swap also means coming up with different brake pedal setup, emergency brake, moving radiator or cutting into the firewall (or both).

 

 

[Old CWO]

Cummins 4BT/NV4500 combo?

 

Industrial trucks deserve industrial engines!