My 1953 F-250 came with a low mileage, great running, 215ci staight-six, 3-speed HD transmission, and 4.86 gears in the rear axle. This naturally makes her a real loud @ 55 mph as the RPMs must be insanely high.

I'd love to keep the 215 but just how sluggish will she be if I were to swap out the 3-speed HD for a regular 3-speed or a 4-speed and re-gear the rear to 3.50's? I'm not looking for high-perfomance, just something I can drive often and be able to keep up with people on the highway.

I'd like to keep the truck as traditional as possible and trying hard to resist the urge to slap a 302, 351, or even worse.. a #####ty 350 in her. I could try an find a 239 flathead or a y-block but both will probably be spendy rebuild and take time to track down all the parts.

Any suggestions guys?

Thanks

- JT

 

[updated:LAST EDITED ON 11-Nov-02 AT 11:29 AM (EST)]A light three speed wouldn't improve it much because the HD has a slightly lower 1st gear. The 4 spd just adds a even lower first gear and has to be double clutched(I don't know for sure). I would change the rear end. You can get a f-250 rear end out of a 73-79. They have a variety of gear selections. I would get one out of a automatic because the ratio would be higher.


Nathan

 

On the HAMB, folks are suggesting a later model 4-speed truck tranny as 4th is normally an overdrive. I wonder how difficult it would be to bolt up.

Here's a good post from Rocky on the HAMB:

"53, eh? If I'm not mistaken, the 53's had the later tranny bolt pattern. I'm thinkin one of the 1980's ford pickup 4 speed [4th was an overdrive] may be what your looking for. The shifter comes right out the top, like any old truck 4 speed. It may bolt up to your bellhousing but I'll bet you'd have to change the clutch disc to a spline that matches your new tranny. The old one should have the 1.25", coarse-spline input. I'd look into that before I began changing rear axles."

Anyone have any input to add? Thanks alot.

- JT

 

A transmission from later would not bolt on. You would have to fabricate it. All the 4spds have very low first gears unless you could find one on those conventional 4spd from the early 80's that have an overdrive 4th. But those are hard to find. I'd change the rearend in our 78 F-250 it has a 3.54.1. I'm going to use one of those rearends in my '51 M-3 (heavy duty 3/4). The 215 shared the same bolt pattern as the y-blocks.

Nathan

 

I've got a 9" rear sitting here, how about slapping a 3.50 or so third member in it?

I don't have a problem changing the rearend so long as the 215ci would still perform ok. We are only talking 91 HP here.

I'd love to find a 254 Flathead-6 but that's getting pretty rare.

Didn't they go with 223 straight-sixes in 1954? Shouldn't that bolt into my '53? There are more perfomance options available for the 223 vs. the 215.

- JT

 

A 223 built to stock late 50's standards is about 140 hp. It would be pretty much a bolt in, plus, not many people woould be the wiser. How about trying to find an overdrive tranny ( mid 50's to early 60's will bolt onto your bellhousing ) for it for better highway cruising?

 

How about this 3-speed with overdrive tranny out of a '57 Ranchero? Unfortunately, it again is a car transmission.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=1872295842

- JT

 

"You can get a f-250 rear end out of a 73-79". Are you sure those rearends are not too wide?

 

I know it'd be too wide. A pre-'72 axle would be a better fit, maybe even a bolt in. I'm not sure what gear ratios are available in the 3/4 ton axles, though. JT, you said you've got a 9" sitting on the floor - what's it out of? If it came out of a '57-'72 truck, I'd use that. The only problem is that you'd have five lug wheels on the back and eight lugs on the front. The bigger trucks - like yours - had 3" axle tubes as do the 9" rears. With the axle clamps on your truck, the 9" will literally bolt right in after you grind off its shock mounts although you may need to get some pinion shims to get the pinion angle right.

 

> JT, you said you've got a 9" sitting on the floor -
> what's it out of?

Brand new housing, never installed in anything. It's too long now but the local rear-end shop says it'll be no problem to narrow to whatever size I want and install the ends and perches for me.

I'm thinking of doing a disc conversion up front so I shouldn't have issues getting bolt patterns to match up.

- JT

 

The 223 is just a bored 215. I have measured a 78 f-250 rearend and it is the exact same width.

Nathan

 

A Ford 300 looks like it'll be the best bang for the buck if I want to stay with a straight six. It's not as long as I thought it was.

However, I am still looking for a Flathead 254.

- JT

 

[updated:LAST EDITED ON 13-Nov-02 AT 10:58 PM (EST)]>I don't have a problem changing the rearend so long as the
>215ci would still perform ok. We are only talking 91 HP
>here.

>Didn't they go with 223 straight-sixes in 1954? Shouldn't
>that bolt into my '53? There are more perfomance options
>available for the 223 vs. the 215.

JT, The early 215's and 223's had vacuum-only distributors. First thing I'd do is get a later distributor that also had centrifugal advance.

Also, I believe that Ford made a 262 that was another variation of the 215/223 family. 1963-64 or so? Should bolt right up and have more power. I'd be taking the head off, installing hard exhaust seats, home porting the ports, and milling it for a bit more compression, too.

Best of luck.

Edit: That reminds me. The valvetrain on the 215/223 seems similar to the Y-block. Seems like you could swap on the 1.54:1 rockers from the 1956/1957 Y-block to get some more lift.

 

Paul:

My problem isn't with the 215, it's with the 4.86 gears in the rear-end along with the 3 speed HD in my F-250.

- JT