A steady and reliable Chrysler flathead inline six engine isn’t where I’d expect to find a home brew turbocharger installed on. But here it is and once the owner explained his reasoning and results it did make more sense then I would have initially though. The car it is installed in isn’t too bad either.
Here is the recipient of the turbocharged goodness, a 1949 Plymouth Special Deluxe two door sedan. A flat grey, red, and black multi-tone paint scheme with painted red steel wheels completes the budget hot rod look.
I suspect with the hood down this late 1980s or early 1990s Chrysler turbo badge likely causes confusion. It isn’t lying as the inter-cooled script has covered with orange tape.
Back to the engine details there is a Mitsubishi turbocharger boosting the low compression flat six. I believe it is a TE04H turbo from a Chrysler Lebaron but my photos of the actual turbo itself didn’t turn out as it was installed down low after the stock exhaust manifold. Some generic radiator flex hoses and pcv pipe connect the turbo to the dual blow through carburetors. The turbo sourced from a smaller displacement engine helps reduce lag and is well matched to the low revving flathead motor. According to the owner one of the biggest limitations of the Chrysler flathead engine is that the heads don’t breath well. The addition of a few PSI of boost brought significant improvements in both fuel economy and power.
The interior looks bone stock except for some aftermarket floors and of course the boost gauge!
The rear view shows the multi-tone color scheme a bit better. The owner had also fit the lowest stock numerical ratio rear axle he could find as well as fitting those extra tall tires in order to keep the revs down on the highway. Apparently it was only partially successful as it still screams at highway speeds.
Bravo, David! (And the intrepid owner of this CC.)
This is why I LOVE CC! You never know what’ll turn up, but it’s always gonna be good.
Some guys will look around, see an old Plymouth and a box of PVC fittings and hoses and stop there. This guy scratched his head and asked, “Hmm… What if I had a turbocharger?”
This is right up my alley…all kinds of cool. I suspect that some of the “boost” finds its way out through the carb throttle shaft bearings, but who’s being picky? Plenty of boost left for that old flathead, no doubt.
Typically in “blow though” carb setup, the whole carb is enclosed in an airtight box for that reason. Love the plastic sewer fittings. So maybe this is what I need to do to my Ford truck, as I have a whole box of fittings.
Yeah I’m not seeing how this would actually be working w/o a pressurized carb. For a carb to mix fuel you need a pressure drop in the venturi to make the fuel be pushed into the air stream by atmospheric pressure. So I have a hard time imagining how this doesn’t go real lean unless the boost is really really low. That is the reason for the pressurized box around a carb in a blow through forced induction system, not because of potential leaks around the throttle shaft. That piece of flex hose doesn’t look like it could hold much pressure either. So maybe in reality it functions more as a ram air system.
I think the key is that it is very low boost. The pcv and rubber hoses are able to contain a handful of PSI just fine. The old flat head gets a breathing assistance.
The carb bowl may be internally vented to the throat in the area of the choke, above the venturi. So the boost would be applied to the fuel in the float bowl. This would balance the fuel delivery. Take a look at the bootleg blow off valve on the top of the pipe. It has a spring hooked to a partly threaded rod that passes through the pipe. There is a plastic wing nut on top that is used to adjust the boost.
If my fluid mechanics knowledge doesn’t betrays me, there will be a pressure drop in the venturi no matter what pressure is fed to it. It will pull and vaporize the fuel anyway.
I would be more concerned about boost leaks (as Paul said) or correct jetting (enough fuel for the air being moved) or spark/timing than the carby not being able to do its job.
If the turbo is pushing say 10-13 psi I think the PVC pipes and the hose should hold. Heat aging would be my concern, but meh, those bits are cheap enough.
And I love the sewer pipe setup. Ingenuity at its best.
A 49 Plymouth with a boost gauge. What a country!
Nice, The first car I remember my parents owning was a 50 Ply just like this. But obviously no turbo. They traded it in on a 58 Savoy, BIG mistake. What I like best about this car is the steering wheel.
Does the covered over part of the badge say inter-cooled, or does it say electronic fuel injection?
Cool car the turbo system does look a bit rough but it obviously works pressure losses are neither here nor there using plumbing fittings and with a blowthru like that it will run low boost pressure or it will not run, He is after extra torque to push taller gearing thats all trying to make one of this old banger keep up with traffic in a modern world.
That old box looks better if your thinking is on the outside. One of my favorite old cars. Much easier shifting through the gears than it’s contemporaries. Love it when someone comes up with something like this.
Good find.
Great car, definitely something different. All the more impressive since it’s not a typical SBC conversion but uses the original engine and a clever power adder, as well as a mostly stock interior, including original steering wheel and fabric seats.
I wonder what kind of aftermarket intake manifold (aluminum, finned) that is. Stock in 1949 (in a Plymouth, no less) would undoubtedly utilize a cast iron manifold with a solitary, single venturi carburetor.
Yea, if I remember correctly the hole at the carb flange on the stock intake was about the size of a quarter. Not great breathing engines.
Love the ingenuity of the home-brew turbo setup! I wonder by “highway speeds” does he mean ~75mph? Also whether anything has been done to the steering or brakes…
It is always fun to discover things like this. There is a ’48 DeSoto coupe running around my area of the country with a V-10 Viper nicely tucked behind that big toothy grille.
“Blown flathead” ―the words alone sound cool; this mod deserves a Gold Star for sheer imagination. So the owner can trounce other antiques while still claiming it has a stock engine.
And the technology is technically period, though it was years before turbos were practical for popular use; e.g., it was another decade before even locomotive builders got into them, following Union Pacific’s experiments. I think most road locos otherwise had only Rootes blowers, at most.
Love the use of the turbo badges on the car. I’ve been keeping an eye out for a pair of “2.6 HEMI” badges off of a k-car to put on my Chrysler Conquest which, in fact, has a turbocharged intercooled 2.6 hemi in it! ^_^
i luv this but want to do it with a single carb on my 236 in my wc63 6×6 anyway someone could post exactly what has to be done and which turbo they used
again as others said low boost is the key just enuff for more air and umph
prt pls