Ok so I am looking at doing a replica of this.
My question is what to do about the front wheels. Ace Cycle Cars builds a replica which uses 5.0x16 front tires.
http://cycle-car.com/specifications.htm
How am I supposed to put 100bhp to the ground with tires like that? Any suggestions on how to keep a period look and make it handle.
Formula vee has the tall skinnies:
some sort of snow rally tire designed to be studded, but don't put the studs in? a bit obscure, but at the 2009 Rally of Great Britain, some teams elected to run the P-Zero Corsa snows without the studs, due to the extreme wetness, and it worked out VERY well for those who did it on the first few stages and soon every team followed suit. that would get you great grip and the narrowness you're after.
alternately, look to Hoosier's dirt oval and vintage racing tires. they have DOT numbers and significant amounts of tread, granted Hoosier says that if they touch public roads you will crash and burn and die, but it could work.
failing those two (or perhaps should be ahead of those two...), look at what Coker Tire has to offer, that seems the most logical course of action, and then for rims, if you don't mind a VERY un-period look, rims designed for rally cars running snow/ice tires?
Coker has large diameter vintage competition tyres... would likely be the ticket!
You can still get custom tall skinny wires... not cheap but not eye wateringly expensive either.
I don't think that an early Ford type spoke wheel would throw off the image:
(just for reference) http://truespoke.net/hotrod.html
A lot of the real Mog (vintage) racers use motorcycle tires. Usually race rubber. Not exactly a prefect solution (because the leaning issues of a bike are different and the bike tires are designed thusly)
I'd be tempted to find some sort of a treaded vintage tire like what race cars of '50s and earlier vintage run. if you could find replacement tires for old pre-war GP racers I think that would be the ticket since those tires often were side-loaded with more positive camber than was good for them, so they were likely strengthened or the construction altered to suit that sort of abuse.
alternatively, the narrowest winged dirt oval sprint car front tire you can find, or if you're REALLY desperate and can't find anything else, maybe a set of DOT approved drag fronts? that might make handling more than a bit iffy but if it's your only viable option I say go for it.
I know this isn't quite what you asked, but depending on the tire, try to design the suspension so that the amount of camber gain works well with the roll stiffness of the front end, and in the name of rear end traction, especially if you use an automotive tire, I would try to keep the roll stiffness as high as you can so you aren't getting the rear tire up on the shoulders every corner or you're going to have lots of funky wear issues and not much rear end grip. not so critical in this particular 3-wheeler, since you're going FWD, but in a RWD 3-wheeler it would be a big concern, I'm guessing
I am not sure you would have problems putting 100hp down on a skinny tyre. If you look at them, they are MUCH taller than tyres today.. so your footprint is not as small as you think it is
I'm building a cyclekart and they use Honda CT90 wheels. They are 17" and look pretty sharp.
http://www.google.com/imgres?imgurl=http://cyclekarting.com/wp-content/uploads/200...
http://www.google.com/imgres?imgurl=http://www.cyclekarts.com/G.D.3.jpeg&imgre...
15s are easy,lots of front drag skinnies or VW 145/155165s out there. I always wanted to use 16s with the aluminum spare rims from the Rx7. They look like 16x4 Minilites.
