hey guys, anybody have any information or random thoughts and opinions on flathead plymouth motors from the early 50s? my freinds and i have stumbled across a few running cars for not alot of cash and they were wondering if those motors are prone to self distruction or if you can get parts for them ect. any info or links would be apreciated tim
The flat head 6 in those were used in fork lifts up to the late 70's so the parts are out there I spent about 2000 rebuilding my motor and puting a small parts kit in the trans and a new radiator
Very durable, forgiving motors, and well made durable cars, most with IFS stock.go to the P15-D24 site for lost of info. A good group of guys: http://merc583.addr.com/cgi-bin/webbbs/webbbs_config.pl
I got one in my 51 cranbrook. VERY tough engine. Ask Blueskies about them. He has a 51 as well and has his rebuilt. He has his own website of his rebuild of his car and it is an excellent reference for these vehicles. I plan on rebuilding mine because it has a blowby problem. Do a search on mopar flatheads, this topic was discussed just about a week or two ago. Seach the member profiles for Blueskies and I believe he has a link to his site.
I have been driving mine in my '53 wagon and it has a blown head gasket. I don't even think it has been rebuilt? They are a great engine if ya want dependability and long life out of an engine. There are alot of sites with parts on the running gear and the motors and your local Kragen, Autozone or Pep Boys has the gaskets if ya need them. That is were I just got all mine to do the head job on it. It ran me about 40.00 for the kit. KNUX!
Forget them, they are lousy engines.drop a v8 into it, but Ill take the engines off your hands, if you pay my expenses. Really now. good engines,good running gear. keep the rpms down, all the torque is just off idle. for more power and a easy swap. go with a chrysler engine, 2in longer, lot more torque.parts are available, I put a251 industrial engine in my 49 biz cp. runs fine.p15-d24 page is the one for info, good bunch of guys too.....waterboy.... ..
I had one in my '37 Ply with 42000 miles on it. I changed it out to a 360 with a 727 auto. That old Plymouth used to go 75 - 85 mph. Very reliable, always start. Wish I had it back.
before i took my motor apart and had it gone thru i drove from bakersfield to paso smokin the whole way runnin at 215 on the temp gauge. when we pulled it apart there wasn't any of the rings that weren't busted. only had to be 30 over and the cost was 1100. the only thing we had to do was slap the rings on and slap in the piston and close her up. sherman tanks.
I'll have my '55 230 back together and running this weekend. They're very durable motors. Just before I took it apart, I drove mine 250 miles on the interstate at 65 MPH on 3!! cylinders and still managed 12 MPG. And the three that were firing only had 60 PSI compression. When I took it apart, every single top ring was cracked, and 3 pistons had holes in them Believe it or not, the 230 flathead that this came out of was still running too....
Engine bearings can get a bit pricey though. retail list is usually in the $60-80 range for rods, and $100 or more for mains. But they can be had on e-bay dirt cheap. I just bought a .001 under rod bearing set on e-bay for $10. Lots of military surplus engine parts avalible on e-bay too. Another durability story... Tractor puillers have been using them for years. Guy I know used to pull, he said he saw a turbo'd nitrous fed flathead lift the head off the block 1/4" during a pull once. They replaced the head studs and head gasket, and it ran fine for the rest of the meet.
Tim- Check out the suppliers list on my '50 plymouth site, click the link in my signature. I put together a list of suppliers that I used to rebuild and hop up my 230 flathead. My engine ran really great when I bought the car, and when I tore it down, all of the top compression rings were broken and two pistons had holes in them. I've heard the same story from a half dozen guys... The parts are readily available because these engine were used in welders, pumps, airport tugs, combines, tractors, and plymouth, desoto, dodge, chrysler cars for years and years. Napa has just about everything... Speed parts are still out there too, if you look hard enough. Pete
61- Yea, I know, I'm a flathead six ***** ... I don't get to the hamb often, and usually there's a few thousand posts to surf through since my last visit. I think this thread was about 5 pages down when I saw it... I usually don't dig that deep, but was bored at work and kept looking. Pete
I don't know about supercharging, but alot pf the pullers use tuirbos. they respond really well to forced induction.
was wondering found this post, i have a 218 in my 50 plymouth, read all about the engines running with busted rings, mine seems to run fine, will run 75mph if i push it hard, smokes a little, gas milage ****s, not fast at take off, just wonder how you can tell if rings are busted when it seems things are fine. have not done comp. test i ***ume that would tell, but just running down the road every thing seems fine??? thanks scott
A compression test will give you an idea on the condition of the rings. A leak down test will give you a better ****ysis on the condition of both the rings and the valves, you'll be able to tell where the compression is escaping. These engines will run fairly smooth with worn rings and poorly seating valves, they will just burn oil and be down on power.
Doubt if you have busted rings. More likely tired rings but these engines are damn near indestructible. They were used as industrial engines for years. Low compression, heavy castings. Low and slow man...not a speed demon... Rebuild will give you some improvement but if it's running save your $$$$ Had a 50 DeSoto with flathead six. Older buddy drove it from Florida to Calif and sold it. Guy that bought it drove it for years, well into the 70's.
Very low RPM range and the 3 speed ****** tops off on direct drive. Subtract the gear reduction on the final drive. This engine is a TORQUE MONSTER, not a hot rod.
The old flathead sixes from Chrysler Corp are foolers. They will continue to run smooth and quiet when in an advanced state of wear and neglect. The only symptoms of wear are, hard to start, down on power, burns oil and hard on gas. Then you know it is worn out. A compression test and oil pressure test tells the tale. Compression should be 110 - 120 PSI. Oil pressure 40PSI @ 30 MPH, 15 @ idle. If you have at least 80 - 90 on all cylinders and 30PSI you are good to go, but should be thinking about an overhaul. Vintage Power Wagons is a good place to get parts ($75 for a set of 6 NOS pistons, how good do you want it?) When in good shape they have plenty of power for all normal driving although, no threat in a drag race. In spite of having only 85 to 110 HP they have plenty of torque at low to medium speeds which makes driving so easy and gear shifting optional. A local guy had a real nice 1941 Plymouth coupe that seemed to be running good but lacking power. He planned on rebuilding the engine and installing a 5 speed or a different rear axle gear for better performance. First he had the engine rebuilt and was amazed at the performance. He had no idea how worn the engine was and how far down on power. It always started and ran, did not make any knocks or rattles and he thought it was ok. The new found power took away all desire for different transmission or rear axle. The car will idle down to under 10MPH in high gear and pull away without stalling or bucking, right on up to 85 MPH.
Here you go 49 Plymouth with a hopped up 265 Chrysler flathead 6, tri-carb intake and split exhaust, shaved head, cam ground to higher lift and longer duration.
Speaking of supercharging... we had a similar question a while ago about putting a centrifugal blower on a flathead 4 cylinder Ford hot rod. I advised that a low compression flathead and a centrifugal blower make a perfect combination. So he installed the supercharger. Then he reported that it ran great, and had great performance for a small 4 cylinder. He went on to say, that he thought his engine was only good for 3000 RPM but it kept on pulling strong right up past 4000. This is why superchargers work so well on these engines. They are built for best performance at low to medium speeds, to run smooth and pull strong even in high gear at low RPMS. But tend to run out of breath at high speeds due to small carburetor, mild cam, etc. A centrifugal supercharger doesn't do much at low speeds but boosts the mid range and high speed performance. Also, superchargers work well with low compression and flatheads typically have low compression, and due to the combustion chamber shape, you can't increase compression very high without cutting off the breathing. Years ago I read a road test of the Kaiser supercharged six. At the time of the test it was a brand new car. The McCulloch blower increased HP from 110 to 140, the tester reported that it made the six perform like a V8 and had no adverse effects, in fact he was a little disappointed that it did not make noise or otherwise make its presence known.
Hey flat six fix that looks and sounds like a great motor, it must be the racing model with 3 carbs straight linkage and no chokes. How does it go when it is warmed up?
Rusty it's not mine, the owner says it goes pretty darn quick. This engine has venola racing pistons, and spins up the RPM much higher than the stock 3600 used in the factory 50 hour tests. My engine is just a semi-tired 251, but has good compression and oil pressure, have a 265 sitting on my shop floor, that i hope to make my hotrod flattie out of.
Here's an off-topic dragster powered with a racing 265 Chrysler flathead 6 cylinder engine 2 spd powerglide racing trans.
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