Keep the original engine or....?

[lostviking]

I'm thinking hard about putting a Fatman IFS and a Cherokee rear end in my truck (1946 WD15). I want to be able to drive it out of town, not just on side streets. I'm also thinking of a new transmission, either a T5 or A833 OD.

 

The question is do I just go for it and change the motor too, or rebuild the original block (as a 230, since I have the crank and rods)? I like the flathead motor, it's smooth and strong with a few mods at least. But a much newer design would probably be the last motor this truck ever sees for me at least. It's not like I'd be holding onto it still being original, but aside from looking under the sheet metal, I want it to still look original. No dash changes since all my gauges are in great shape.

 

The thing is, I have two transmissions and two motors. The original 218 needs a rebuild, but only had maybe 60K on it. I have a 58ish 230 in her now. If I do swap motors, I will offer up the original parts so they get used, not trashed.

 

What do you guy's think?

[JBNeal]

These trucks were designed around the flathead, so any other engine will more than likely require modifications to firewall, motor mounts, frame, etc.  That steering gearbox is usually the fly in the ointment, as any V-block exhaust manifold will be awfully close...larger displacement in-lines will be an issue for radiator placement and firewall interference...diesels may cause frame cracking from vibration...on one of my daily driver projects, I've about decided on retaining the flathead and upgrading the rear axle to a 3.73 or 3.90 if I can find one and keeping the original transmission as T-5s or Dakota 5spds are scarce in my area for some reason.

Edited December 29, 2020 by JBNeal
information dismissed as irrelevant

[55 Fargo]

Depends on which trans donor you go with.

On an A833 OD trans with either .71 or .73 in OD you want either 3.73 or 3.55 at most. 3.90s would work okay too.

On T5s, early S10 T5s had a .86 5th and 4.03 1st gear. So a 3.23 to 3.73 might be ticket.

On a V8, not a big deal a 318 or 360 off center to right to clear steering box. Cutting a firewall is not necessary at all.

Fabbing motor mounts, trans cross member not much issue.

On B series trucks you will have to mount a brake pedal for MC. On my C series I was able to use stock pedal and MC.

Im running a fairly stock later LA 318/904 combo with 3.23 gears. Love this and would not dream of going back to a flathead 6 in this truck.

You gotta decide whats best for you.

 

[47 dodge 1.5 ton]

I was up to see George Asche about a month ago and went for a ride in his ‘50 Plymouth w/230. Very mild motor with dual Ball & Balls, head milled slightly. That car will run 65mph all day and 85 if you need to. He does have an O’drive installed. Unless someone needs to be drag racing, that 230 makes plenty of power for a car/ pickup in that weight range and runs smooth. If you really want to keep the clutch/brakes & wheels, I would do the 230 and add an OD trans. That’s only my opinion! 

Edited December 28, 2020 by 47 dodge 1.5 ton

[55 Fargo]

24 minutes ago, 47 dodge 1.5 ton said:

I was up to see Gorge Asche about a month ago and went for a ride in his ‘50 Plymouth w/230. Very mild motor with dual Ball & Balls, head milled slightly. That car will run 65mph all day and 85 if you need to. He does have an O’drive installed. Unless someone needs to be drag racing, that 230 makes plenty of power for a car/ pickup in that weight range and runs smooth. If you really want to keep the clutch/brakes & wheels, I would do the 230 and add an OD trans. That’s only my opinion! 

When exactly were you at Georges place? I thought his 50 was down for repairs, on the road I take it?

[47 dodge 1.5 ton]

My father and I was up to see him on the 13th of November— the Plymouth was running plenty healthy as well was Mr Asche?

[55 Fargo]

14 minutes ago, 47 dodge 1.5 ton said:

My father and I was up to see him on the 13th of November— the Plymouth was running plenty healthy as well was Mr Asche?

Wow November 13th and no masks?

George tested positive for Covid 19 and is just getting out of hospital. 

[47 dodge 1.5 ton]

I didn’t know that, I know he mentioned he wasn’t feeling up to par shortly before our visit, we have been lucky down here, just starting to get cases close to home. I think we have spoke on the phone around the end of November. How long was he in the Hospital?

[55 Fargo]

George Asche was hospitalized on November 25th as a result of testing positive for Covid19. He has received treatments and will be discharged real soon.

At almost 89 he is very lucky to have lived through this.

Just an FYI.

[47 dodge 1.5 ton]

Sorry to pull this off topic, appreciate the update.

[lostviking]

No worries, this is a social website.

 

Thanks for the replies. I don't see any problem with a sb Mopar either. I've read about plenty of them being done. I know there is room, without cutting the firewall. I don't really need to worry about the steering box either as the Fatman front end is rack and pinion.

[B1B Keven]

Keep the 230, add some go-fast stuff to it. Later add the Cherokee rear axle and/or the 5 speed.

 

I drove my '49 all over northern Ca with the 4 speed, 218 and a 3:23 rear axle out of a Charger.

 

Drove it from Susanville to Bishop one year for Mules Days.  ?

Edited December 29, 2020 by B1B Keven

[NiftyFifty]

In my experience I wish I could go back and do exactly what you’re pondering, I started my truck with the idea it would just be for short tours, but that gets old soon and once I started investing money in switching to disc brakes and upgraded master cyl and later on rack and pinion steering and many other upgrades like a 251 with lots of go faster parts I still have a truck that isn’t comfortable for real long trips and although I can cruise highway speeds, at 70mph the old leaf spring suspension wasn’t really made for that.

 

If you want a comfortable long distance cruiser then I would recommend the IFS and a reasonable V8, others may disagree, but I’m only going on my personal truck and experience 

[55 Fargo]

10 hours ago, NiftyFifty said:

In my experience I wish I could go back and do exactly what you’re pondering, I started my truck with the idea it would just be for short tours, but that gets old soon and once I started investing money in switching to disc brakes and upgraded master cyl and later on rack and pinion steering and many other upgrades like a 251 with lots of go faster parts I still have a truck that isn’t comfortable for real long trips and although I can cruise highway speeds, at 70mph the old leaf spring suspension wasn’t really made for that.

 

If you want a comfortable long distance cruiser then I would recommend the IFS and a reasonable V8, others may disagree, but I’m only going on my personal truck and experience 

While I can agree on power plants I suppose.

There are plenty of lighter cars with a flathead 6 hopped up and some type of OD trans that should be no issues with longer travel excursion.

Engines pulling the cars really shouldn't make any difference if powering the vehicle as needed. Blueskies 50 for instance, nice long distance cruiser. 

The cars from 40s on have decent riding suspensions.

On the bigger heavier trucks ( my 108 wb aint too heavy) the heavy suspensions might not be so much fun on longer drives.

In my case, will redo my bushings springs and shackles at some point.

But in all honesty handling and ride at 70 mph on a smooth highway is not bad at all. Its bumpy winding roads where it aint so much fun.

With respect to a swap, I thought I may never have said this, but my 318/904 combo os friggin great, I truly love it 

With 3.23 gears goi g 0 to 65 mph is as fast as my 2015 HEMI Ram. Off the line she hauls real decent.

This is with a relatively stock LA318 higher compression engine. A hot 318 or 360 would be hairy scary...

[Jeff Balazs]

I think it really depends on how you want to use the truck and what sort of experience you want out of it.

I have been using my slightly modified 52 B -3-C daily for about 5 1/2 years. I put anywhere from 100 to 150 miles a week on it here in Southern California. It gets used in relatively heavy fairly quick moving surface street traffic most of the time. I am very comfortable driving it this way. It isn't the quickest vehicle on the road but it has been rock solid reliable. The only significant mods I made is a 3.55 Grand Cherokee rear end, 4 wheel disc brakes and a 6V positive ground alternator. I didn't do any suspension or spring mods and it rides pretty darn nice. It works for me but I have never taken a trip over 2 hours in it. If that works for you then at least you know it is achievable.

 

If you want a lot more than that out of one of these trucks then you really need to make some serious modifications. Not just an engine swap.

For me taking it just so far has worked out. It runs and drives better than I expected for an almost 70 year old truck. If I ever need more I will drive something more modern. But probably not. ?

Jeff

 

[55 Fargo]

If you have a stock suspension in preemo shape and possibly lowered.

A good braking system and tight steering.

Adding a more modern power train is a night and day difference.

You cannot compare a Flathead 6 with my 318. A heavily modified 230 or 265 can and will have HP rating of a stock 2 bbl 318. But it does not take a whole lot to warm a 318 up.

Off the line, acceleration on passing on highway my 318 is a race engine compared to flathead 6.

And the beautiful thing is, the 318 has decent fuel economy and bullet proof reliability.

[lostviking]

After a lot of thought, I have decided to sell off my two motors (one running in the truck, the other in pieces) and transmissions (one in the truck, the other a rebuilt I got with the truck). When I do the front end, which I will be doing, I'll set it up for a sb Mopar. I also plan on a Cherokee 8.25 rear end. Depending on tire diameter, either 3.55 or 3.73. The later seems to be a lot more common.

 

Thanks for all comments.

[wayfarer]

Have you looked at the Dakota front clip vs the fatman?

[lostviking]

Not really. I don't like the idea of cutting part of one frame off and welding it to mine after doing the same. The Fatman IFS can be undone, since there are no changes to the frame other than some welds and fish plates. Chopping off the front of my frame is not.

 

I know some like this approach. I see it as something that was done when there were no alternatives. I do like all Mopar, and the brakes on the Fatman are not, but that's not much of a problem for me.