Engine swap

[1950 pilothouse]

I’ve been trying to upgrade my 218 flathead. Starting to wonder if it wouldn’t be better to do an engine swap. I like have the flathead because it’s unique, I have a 225 slant 6 and was wondering how hard is it to swap? Would the floor have to be cut and radiator moved like a v8 swap? Has anyone tried this?

[Plymouthy Adams]

I understand the having the slant 6 on hand and wanting to use it...it is quite power plant overall but you just stepping forward in technology by one year.....the length of the slant 6 is as much a problem as adding any V8.  Before making the call I would ask you study it a bit more before starting the transformation.  It is a bit of work involved that will as I said, still limits you overall verse a more modern V6 or V8.    late model Dodge V6 engines are running as much as 305 ponies from 221 cubic inches...

[1950 pilothouse]

True. It was just a thought, I love having everything original on my truck just trying to figure out how to get more highway speed without cutting it up

[Plymouthy Adams]

most start with a rear ratio change as our highways today are so vastly improved over that of when these vehicles were built.   Other will actually run the engine to its designed sustained running RPM of 3600 

[1950 pilothouse]

Thinking of doing a carburetor swap. Looking at 2 barrel adapters. I think that would give me enough power but the two 1 barrels look better.

[Plymouthy Adams]

if that is your plan...then run with it...and report your results...

[wayfarer]

I really doubt that adding 6 carbs would make up for a gear change...the rpm will still be the same.

If the fan noise at freeway speed is causing you fright then swap to a clutch unit.

[59bisquik]

A rear gear swap to 3.73’s in my 55 got me cruising down the highway at 70 all the time. It had plenty of power to pull the hills. However, with the RPM’s, fan and glasspacks, it was a tad noisy. However, much easier and economical than an engine upgrade.

 

[1950 pilothouse]

Did you swap gears or rearends? 

[Plymouthy Adams]

depends upon your initiative and luck searching local yards for better gear ratio for the axle of the era...else, many do the modern rear gear upgrade not only for the ratio but for the floating brakes.....this eliminates the puller and the need for the brake tool for the rear axle.  

Edited March 11, 2018 by Plymouthy Adams

[Los_Control]

I would say the rear end swap would be first in line, even with the slant 6 you would want better gearing.

Then would consider upgrading to disk brakes in front, simple and reasonably priced.

From there I would consider if wanted to upgrade motor and trans.

 

I hear that 2 single barrel carbs will distribute the fuel more equally then a single 2 barrel.

More power and economy ... vroom vroom!

[1950 pilothouse]

Yea I heard that too. Reading a lot about the manifold has to be heated to run duals? Anyone have experience with that?

[59bisquik]

I lucked out and got an R10 overdrive transmission and a 3.73 gear set from a 54 Plymouth. The gears are out there but require searching. A Ford 8.8 is much easier to find and has a ton of gear ratios available and disc brakes. I guess it depends on how original looking you want to keep it.