So far, I've been laughed out of every Britcar DL in which I've posted this query -- if no-one here can help me, or if this is the wrong place entirely, please point me to another more likely place (and not that HOT place down below -- I've already been given THAT suggestion!)
I'm building what I suppose would be called a component car, except all I have is the bare GRP body, a metric ton of mechanical gubbins (mostly MGB), and an enthusiasm for clever engineering. I have a splash of an Ambro body, the original of which was designed and produced by the team of Bill AMes and Dewey BROhaugh in about 1959. The body was originally to be fitted on a Triumph TR2/3 chassis to compete in SCCA Modified classes, and indeed many were. Others were mounted on everything with a fram you could think of, and Ambro eventually offered a bespoke chassis that was run with everything from a 2-cylinder Panhard (maybe) to a Ford V8 (definitely). Ames and Brohaugh were also responsible for the bizarre-but-effective "Peyote" special, and if you've ever seen it, you'll know how it got its name.
So much for the body, except that it is designed in five pieces to accommodate wheelbases from 88" to 100", and a track of about 50". It looks very much like, and in all dimensions is nearly identical to, a Lister "Knobbly." Some people, including the guy at CARS in Oklahoma City who's still producing the bodies as the Dio "Tipo" think it looks like a Tipo 60/61 "Birdcage" Maserati, but I can't see the resemblance myself. BTW, the owner of CARS is producing the bodies with the consent of Bill Ames, and CARS made the molds from a splash of what Ames claimed was the last, surviving original Ambro... now it's thought that the body Ames had might have been *itself* a splash from an earlier body, but as there's little fine detail, once painted, you truly can't tell the Dio "Tipo" from the Ambro. The fiberglass work on the newer bodies is technically much better, however
Sorry, I get long-winded.
Now for a chassis (and this is the point where people usually look at me like I'm a Martian. I'm *not* a Martian): as a keen admirer of the work of Frank Costin on Jem Marsh's Marcos cars, a casual student of experimental aircraft construction, and a great believer in Herb Adams' "torsion box" semi-monocoque chassis construction, I'm making the chassis out of 1/4" and 1/2" marine-grade plywood. I could show you scads of drawings, but let's just say that if you're familiar with how the Marcos GT and GT1800 were constructed -- not only interlocked torsion-boxes and deep sill structtures ( a l=E1 M-B 300SLR) to compensate for the big, open cockpit hole, but 'glass bonding of the wooden chassis structure to major areas of the fiberglass body as well
-- then you'll know what I'm attempting to do.
A lot of people take these bodies and put them on a whomping great steel-tube chassis, then stuff some American iron lump in the thing -- like people used to do with Devin and suchlike bodies in the '50s. I don't want to do that.
What I want to do is mate as much MGB running gear, including engine and transmission, with the wooden chassis as I can. I'll be using sandwich-steel-plate reinforcement at all suspension mounting points, and I was particularly drawn to the MGB because, even though it's unit-body construction, the separate (bolted-on) boxed stressed-steel front crossmember carries ALL the front suspension AND the steering rack, at least keeping (one hopes!) the suspension and steering in alignment.
My primary question (I *knew* I'd get to it eventually!) is about caster. I've searched through the Bentley shop manuals and everywhere else to find a value for the correct camber, but apparently no-one envisaged mounting the crossmember to anything BUT a unit-body MGB shell. I want to make sure I design the mounting right to maintain original caster -- anyone have any ideas?
I'd also welcome any thoughts, suggestions, ideas, tricks, hints, whatever -- as long as it's not *personally* obscene! I'm an ex-model machinist (ex-a lot of things, actually...) and a dab hand at woodworking. I'd like to keep the MG drivetrain (though someone on one of the Britcar lists told me the engine block is a spongy old load of codswallops): the 91" wheelbase and 50" track drop it right into the parameters. I hope I won't even have to alter the prop shaft.
There's my story. Lemme have it!
Cheers
Bart Brown