90cc is not huge, but more is more, and will be of some notice. I did consider aftermarket forged units of larger size, say 102 or 103mm, as I've done that in the past. Forged units need more clearance, they rattle when cold... they will take much more abuse, but a 4.5 inline 6 produceing even 300 hp is not even breaking a sweat.
I would like to dyno it, but getting to a dyno may not be easy. I had a chance to take it down the 1/4 mile last fall, but skipped out... what a loser I am!
This I can throw out there... I do know a place with an engine dyno that does engine developement work, anyone care to chip in?
The only current realistic ($$) way to "stroke" a 1FZ is to weld and machine the crank. Though I have never run a welded crank, I have read about issues with them. Just not a fan... they seem hack to me... only useful for a restoration or something.
Most gains will come from improved breathing... this engine is severely corked up.
Many pics and notes to come!
I could do a V8 swap, but why? This is a BIG beautiful 6 with an excellent cylinder head... it will match a 4 valve V8 of similar size quite easily in the power department, and out live it.... Not to mention the adapters and electronics of such a swap, fun stuff, I've dealt with 350TPI bowties in Jeeps, and swapping VR6 VW engines into old 4 cylinder GTI's... I just want to see what it (1FZ) can do.
There are other external area's to mess with, manifold to converter pipes, maybe a true dual exhaust... let the fun begin. Robbie has built a couple 1FZ engines, he had some good info in previous posts, maybe he'll chime in again.