Be careful what you wish for...
I took an outdated purple plate engine with Dyno 89-7exp cam and a Horstman 3 stage pipe and bolted it to my '72 Mont. Wards front tine tiller.
Didn't take long to ditch the straight pipe, btw. For a while I kept it on alky, then got tired of refilling it twice before I finished my tilling, so I changed the jet back to gas.
I kid you not, that old tiller would flat dig to China @ 4000 rpm.
The real problem was that the OEM design didn't accommodate for more power and rpm than stock, and after just a couple of seasons it tore up the transmission.
Like most things around here, I never got rid of it, but I'd take that tiller over my super kewl new(er) rear tine tiller any day!