What about a Jag XK inline 6 ? I was talking with a friend who is into British Cars and he suggested using one. And he has a couple of examples laying about Whatayathink ???
Not too much later there were several slingshots built with the XK and I believe one or two are still extant, though those may be E versions. I don't recall anything earlier with a 120 engine but they were certainly around then. I do recall seeing the occasional 120 car at a strip but the factory gearing usually proved too tall. Personally I'd love to see one in a HAMBster, for the variety if nothing else. With proper gears it could be a real fire breather and the 120's certainly do fit within the rules.
When has fuel consumption been that much of a problem in a drag race car? I say if you have one, build it!! The engine has been around for many years and has plenty of potential.
Your late. I am already building one. I have 3 more if anyone wants one. I think it can make 500 hp. I now need a ch***is and from what I hear Hamby has a nice new one that work really well. Might pick his brain.
I had a restoration shop in Los Angeles in the early seventies. Built several Jag six cylinder engines. The engines are pretty straightforward. I think the only special tool was to degree the cams. I don't think you could possibly improve on the stock three-carburetor set up. And for God's sake if you buy an engine manual for the job ...the number 1 Cylinder is at the firewall and the number six cylinder is the front cylinder. This nearly drove me crazy on my first rebuild. The cars were fairly slow up to about 70 mph but would run a actual 150 mph. This was carefully calculated by recording approximately 24 seconds to go the one mile from Florence Blvd. overp*** to the Firestone Boulevard overp*** at 3 A.M. on the Harbor Freeway.
That would be back when there were few cars at 0300 on any of the local freeways of course, our favorite was the then brand new 210 through Glendora at that hour. We settled many a top end brag there. These days there's no time they aren't busy.