Im about a month away from selling my house and finalizing my divorce. In doing so, I'm in need of a good project to keep me busy. Im thinking about an early style front engine dragster with a flathead six packard or studebaker for power. One of the things I'm trying to figure out is how to couple the Trans to the rear end. I know for common transmissions and rear ends there are couplers available. I've thought I could take both yokes, have them turned down, then sleeve with heavy wall seamless tube, then weld it up. Then i started thinking, with not dealing with big power, could I just use a u-joint between the two? Im thinking it could allow for a little misalignment, or am I missing something, and that's a terrible idea? Haha.
How about one of those constant velocity double u-joints? I’m assuming the rear will be solid mounted, as well as the engine. That would give you a (very) short drive shaft and a little flexibility to boot
Acceptable/typical way is to use an alignment bar to have a straight shot through the main bearing bores, transmission and pinion. Then using a male/female coupler to connect the trans output to the pinion nose. Using yokes and a U-joint isn't recommended but I'm sure it's been done. One reason against it is that a U-joint and the needle bearings on the cross need some movement to not just wear notches in the cups and cross to cause failure. Good luck with the build. Keep us informed as you develop a plan and start the build. Lynn
Thanks for the replies. I'll have to see if i can find someone local to machine a coupler. Im not sure what rear end I'd use, but more than likely will use a t86 or t90 3 speed for the Trans. Doubtful that will be an off the shelf coupler haha. Using a double cardan joint like what Dave G is talking about seems feasible and probably much cheaper than a custom machined coupler. What are the hamb dragster guys using? Short driveshafts, or couplers?
Since it sounds like this is not trying to set the world on fire or set obscure records, I'd try to find local guys who you can bounce ideas off of and inspect their cars. I'd also contact a local fab shop and find out if they have the capabilities to handle doing the majority or all stuff needed. You don't want to call across the country for one of the thousand parts that go into one of these. https://www.bing.com/search?q=race+car+builder+Oregon https://www.google.com/search?q=race+car+builder+Oregon https://www.ecosia.org/search?method=index&q=race+car+builder+Oregon There is the careful methodical plan each detail way or the just grab everything and start in on it way. Where you are on that range will be up to you. I'd make sure to have the latest rulebook for the tracks you hope to run.
The fab side of things I have covered. It's the machining I lack at, so trying to keep that at a minimum. I've got a bender, welders, plasma, press brake, 8ft jig table, but no machine tools. I should probably invest in an old lathe and mill.
Hey, if nothing else, good luck. A buddy of mine lost everything in a nasty divorce and when seeking advice from a priest ( I guess that he had no money for a psychologist). The priest told him to get a project. One 1959 Corvette for six grand, this was many years ago and the car was pretty much at the end of its life. Sorry I can't offer any advice on your front engine project. Today, my buddy is driving around a beat-up Corvette with wife number 2.
This is the proper method if you will not be running rear suspension. EDB Sample pic attached, you can get from Strange, Mark Williams, et al.
Don't use a single U-joint. They are designed to work in pairs only. A CV joint would work if you can find something, but a real dragster coupler is what it really wants. I'd call Mark Williams or one of the other old school suppliers and ask if they can do a custom.
My 1st gas dragster had a single u-joint. It was run with an ohc427 and a c6 trans. The builder ran many seasons that way. I ran 2 seasons without any problems. From what you describe, I would expect you to have around 200hp. I don't think that will break much. Having the alignment correct will be the determining factor in life. Also, a good shield incase there is a failure of any kind.
If you don't have an engine now I'd be looking at engines that have decent parts support as far as internal parts go. If you want flat head I'd think more on the line of Mopar flathead six from the early 50's. I'm just saying investigate parts availability and cost before you snag a specific engine, that may include being able to hook a real short transmission to it.
I don't have one yet, but do have a line on a couple Stude big sixes. I've also thought of just doing a ford banger powered dragster.
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