I just bought a 1937 plymouth sedan with a 201 flathead in it. I am new to flatheads in general and i have been trying to read up on some ways to make this engine faster than the original rating of 85hp and around 140torque. I dont mind about sacrificing a few mpg, as long as i can get above 10 ill be happy. Any suggestions on how to give this engine a little more pep without spending a whole lot on it? Austin
These engines benefit most from a compression increase, and that's also the most cost effective mod you can make. Remove the head and get a rebuilder to grind 60 or 70 thou. You can go to 90 thou, but it's better to stay safe with an engine that's not sparkling fresh. This will give a good noticeable power increase at all revs. Langdons sell an Offy twin carb manifold for around $230 or so, which will give some increase in higher rev performance, and a split exhaust is in the same league. Do a search on here for posts or threads by Blueskies, Bloody Knuckles or Don Coatney. These guys know plenty about these Mopars. There's a forum for Mopar flathead sixes at www.p15-d24.com which will give you any amount of info, also one at inliners international. There's a father and son team on those two forums called Hud and Hudsonator who possibly know more about hopping up these engines than anyone alive.
Check out my website for some giggles on how I took a 169" Stude flatty and turbocharged it for $200 (TurboStude.com). Turbos are cheap and easy on the bottom end.
Thanks rockabillybassman, ill keep that in mind and ill check out that website and posts. also turbostude, ill try and check that out but would it just be a regular turbo? I have no idea what would fit it and be right for the car. was any fab work required when you did it or did it bolt right in?
Breathing on a 201 will yield the HP of a stock 218, breathing on a 218 will give you the HP of a stock 230, breathing on a 230 will give you something worth doing. And since the blocks are bolt in swaps its an easy deal to do. Maybe mill the 201 head a bit, more on that later, open up the exhaust and get an adapter and mount a 2bbl. Then drive it. All the while look for a later 230 45 and later in Plymouths, and 41 and up Dodge and Dodge trucks (although some dodge pickups used the 218) Its a bit confusing but the difference between a 218 and a 230 is the stroke (rods and crank). You can make a 218 into a 230 by swapping them over. There is a pipe plug above cylinder #6 when you pull it you can put a piece of wire through to ride up ad down onthe piston, measuring its ovement will give you the stroke 4 3/8=218, and 4 5/8=230. Any way if you find a 230, use the 201 head on it and deck the 230, by .015 or .020. The 201 head has smaller Cumbustion Chambers than the 218 and 230 so if you go drastic on milling the 201 head and then swap it it will actually have too much CR. I have a 230 with .010 off the block, .040 off the head, and .005 overbore. With dual carbs (Stock 1bbls) it moves along pretty good and gives me 18 to 20 mpg. This with 4.11 gear (but tall tires) Remember your dealing with 6 V positive ground if its still stock, make sure you primary battery cables are 1 gauge minimum for proper performance of the starting and charging systems. Good luck. They are easy to work on and dependable, engine parts at Egge, and Terrell in texas (no website ad in Hemmings) and vVntage Power Wagons. Now if you fid the 230 and go the turbo route, keep us all posted. Lots of MOPAR flat 6 info on the P15 D24 site and forum. When looking for engines keep in mind thee are 2 common versions, the 23 inch Plymouth and Dodge versions, and the 25 inch, used in Chryslers, Desotos and all Canadian made MOPARS, Just measure the head if in doubt. Engine numbers in the block below the head above the gennerator, P=Plymouth D= Dodge, C=Chrysler, S=DeSoto T=Truck, and I= industrial ( which may be found in both lengths) first 2 digits after the letter are the Model Number. Your should be P 3 or 4 the numbers will increase as the cars get newer P15= 46-48 plym my 56 is a P 28.
thanks for the input. My dad is more into going fast and wants me to put in a 350 but i like the flatheads so i think ill take your advice and start looking for a 230
oops typo, the plymouths starting using 230, in 54 not 45. And if you do succumb to the siren sog of the V8, keep it Mopar, 318, 340. Also you can put the 25 inch engines but you need to move the radiator forward which needs some fabrication due to the increased lenght.
i will try but my family is mainly chevy and pontiac so if i wanted to use an engine lying around i could take my pick of ateast 10 chevy engines and 5 pontiac ones, but i dont forsee me changing the engine for a while since i am currently a poor college student. if i change it in the future i will try to keep it mopar.
I read your article a few years ago. got a good kick out of it, making up parts from whatever you could find or make. I saved it so I can go back and get a chuckle on a turboed home built Studie flathead, frying the new clutch! Whats up with it ? have you gotten it up and running yet? Was a funread and makes me want to do that to my 39 Buick Century.
Well, About the time I was on the street with that car, I started a new project with 4 friends to run a 53' Stude coupe at Bonneville with a refined version of the TurboStude's engine. I used the 190" truck version which had 3" mains and built a special head for it. On the dyno it was making 235+ horsepower and 289 foot-pounds torque using the carb and turbo from a 78' Buick Regal. Set two land speed records with it. See the Salt2Salt.com website. The bullet-nose needs the turbo rebuilt now, and the bellhousing needs re-alignment. Planning to do another draw-thru on the bigger 245" Stude 6 for my 37' Stude. The turbo in TurboStude was a discarded TO-3 from an 80's Chrysler LeBaron. They can be had for peanuts. Rebuild kits are about $120.
thanks for the advice. my dad is pushing for me to just leave it as it is for now and if i want to do anything put a v8 in it but i like the straight six's
Stick with the flathead. You can do a lot with these but will never be fast. However, a clean nice flathead will draw a lot of attention as they stand out among the sea of V8's. Here is mine, also check out Pete 'Blueskies" site at www.50plymouth.com he has a great looking flathead.
Happy to see another flathead six kept under the hood... I've had a ball with my "boat anchor". My dad and brother are also dyed in the wool chevy hot rod guys, and you wouldn't believe the amount of flack I've taken over the last 9 years for keeping my flathead. But then again, there's always a crowd under my hood at shows, and no one even notices their 350 V8 engines... Keep the six, you will be glad you did. Pete
I think it's great that you want to keep a flathead in your car. I find that it's a lot more interesting to check out the cars at cruises and car shows that have unique power plants (ie, not Chevy V8s) in them. While researching my Engine Oil Article, I had a look at an ACCCC member's 1938 Dodge D-8 manuals and noticed how similar the recommendations were to my 1965 Valiant manual. If you don't have an owner's manual for your car, the following page might be of some interest to you: Chrysler Engine Oil Recommendations
Very nice! I think I am going to put a 230 in my 31 Plymouth. We took it out of Dad's 54 Dodge we just built (put a 273 V8 left over from his 64 Barracuda)...any leads on who sell rebuild kits? Don
yes, I like to see any old or different engine in these old rods, and sure they wont put out as much horsepower but there's more to having old cars that go fast with modern power and air conditioning etc. I havto admit I have gone thru those phases, and recall some fast 4 barrels, flatheads, and sixes. I was one of the first in my area to run a chevy V8 in my model A. It was new, it was different, we were using whatever was coming into the modern cars.These old engines are reflections of the old days using old time performance mods, and also some modern technologies. These guys are doing developement work on antique obsolete technology, using imagination thought and enginuity, and some of them are pretty fast.One thing i notice many times when people want to hop up an engine they don,t look for bigger and better engines in the same family. The larger mopar flathead 6's like the dodge truck, desoto, chrysler, 265 in. engines. One of my buddies had a chrysler 6 in his 49 plymouth, and he ran the crap out of it, and it hauled pretty good. check this out http://www.olskoolrodz.com/forum/showthread.php?p=666973
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