I would have to say it will have a definite external visual inspection. By sleeper we mean to have something nasty under the hood with a classic hybrid hot rod look from the outside. IMHO the 810 is not that well known although it has an L24E in it, which is really a 240Z/280ZX on a hardtop body. I just want people to look at it and say "Wow! Look at that thing, all blacked out, lowered with this huge exhaust. WHAT IS IT?" When the die hard V-8 guys say “Look at that Ricer POS,†and the GF cracks into it so at the next light as they are picking their jaws up off the floor, we can look over and smile. Sleeper is one thing but we are building it for our enjoyment and others surprise.
I would have to disagree with a Honda motor, only because my first choice would be to use something from the Nissan/Infiniti family. Then once those are exhausted, go to something proven such as a Toyota or GM power plant of course not knocking Honda or the others. Funny you mentioned a Mazda Rotary. My buddy just bought a 1985 GSL-SE w/ 80K original 13B. He owned the similar car 10 years ago and bought from Mazda a brand new 13B. To this day it is still bagged up and he never put in his SA but sold it instead. This could be another possibility.
I don’t think I would want to “rice†the 810 out in any aspects. Sleeper is one thing, ricing it out is a totally different bag of Uncle Ben’s.
My definition and your definition of a sleeper have two different meanings. I still want mine to look cool, albeit with the Type R badge it would look even cooler. I would rather have people comment “Wow, whatever it is, it looks cool and shits and gets too.†I guess I could take it to the rice route and put some Pep Boys 14†spinners, Type R badge, “cold air†intake and a set of General tires. Not to mention loading the underside up with neon and capping it off with a F40 wing. Chances of this happening were better 18 years ago, today highly unlikely. lolol