52 plymouth run stock 217 or upgrade to 318

Hello. I'm new to Mopar and bought a 52 Plymouth Cranbrook sedan. I have the opportunity to pick up the original (matching number) 217 engine for the car or upgrade to a dodge 318 with a 727 trans... My questions are: is the matching number engine that big of a deal? What transmission would I use on the original 217? Would the 217 be freeway friendly? Or would the 318 with 727 be the better alternative? I love the look of the flat heads but I've never had one before. Thank you for the guidance.

 

The matching number would not be a big deal to me, but than again, I take pride in the fact that 2 of my cars (50 chev & 46 ford) still have the original engine. I had a 52 Plymouth once and it had a factory 3 speed over drive. I have seen the T-5 behind the mopar 6 numerous times in the recent past. An adapter is made. With an OD, the 217 would be highway friendly. I drove a 54 dodge panel truck, with standard 3 speed, from California to Colorado once, and had a great time. The mopar flat six is one of my favorite vintage engines, and would encourage the use of one. This facebook group may be of help. https://www.facebook.com/groups/1538690633121968/

 

@504640 thank you for the info. I had heard something about a T5 being used for the 217... I wasn't sure if I maybe heard wrong though... thank you. My heart is kind of leaning to the original flathead...

 

Hi. The key to it being Hwy friendly is the ring & pinion gear ratio or whether you have an overdrive or not. Most of the old six cylinders had a very low rear end ratio. Many had the 411 rears as did my 46 Chevy coupe. Back in that time period the roads were for the most part terrible and we were taking our life in our hands driving over 50 or so. So most cars were designed to run at those low speeds.

To make it Hwy friendly without screaming the engine apart I changed the ring & pinion to a 355 and on the rear tires went from 600/16 to 700/16. Now it cruses down the road with the rest of the traffic at 65 - 70 MPH at around 2500 or so RPM - about the same as a modern car without overdrive.
From my avatar photo you can see I pepped up a 1957 Chevy 235 cubic inch six so it is not bogged down with the larger tires and new rear end ratio.

I have the Clifford intake & headers & they also make them for the Plymouth six I believe.
I added a street cam, bored 0.060 & a few other goodies & although it is not a race car it gets down the road very good.

This way I am keeping the body original & with the hood raised it looks very similar to pepped up original engine although those that know their engines can tell it is not the original Chevy 216.

I do a few local shows & Cruise in's around here & I can tell you that my little six draws more lookers with many questions than does the more common street rods with their small block V8 Chevy's.

I am still down trying to finish the new wiring and air conditioner & about to bust a gut to get it back on the road. Hopefully it will not be too long.

What you do with yours is totally your choice. If it is not going to be a race car you just need to consider keeping the RPM down at today's Hwy speeds and perhaps going to the Bias tire radial look alike as I did. The Bias tires are not very safe at 65 - 70 on most of today's Asphalt roads and want to follow the variances in the road & do not run real straight. The look alike Cooker radials hold a straight line and made it a much more drivable car.

As you get into working on the Plymouth start a build thread on the Hokey *** message board and keep us posted & ask whenever you want some opinions. There is sure plenty of opinions here.

Good luck with it. Jimmie

 

Jimmie thank you for the info. My ultimate plan is to cruise to the plymouth around reliably... I plan on driving it up to northern California once or twice a year and to Vegas a few times a year... and of course cruise it everywhere in between. I don't want a race car and 65-70 is more than good for me... I have heard about swapping a T-5 trans from an S10 into it also swapping the rear end to an explorer rear end this way I have modern gear ratios and rear discs.... what is your opinion of that? Thank you again.

 

You can do a lot with the Plymouth flathead to make it highway worthy and reliable. There are vintage "speed" parts out there if you look as well as new and repop versions.

The T-5 is a good option as is the Borg Warner R10 overdrive if you can find one. One consideration with the T-5 is that you will have to work out an emergency brake somehow because the stock emergency brake is on the tail of the transmission.

I am running a 59 model 230 with a 53 model R10 in my 48 Plymouth. It will run 70 all day long.

230 2 by hkestes posted May 26, 2012 at 12:06 AM

230 by hkestes posted May 26, 2012 at 12:06 AM

230 1 by hkestes posted May 26, 2012 at 12:06 AM