If you have a class limit you could just use a smaller L series like the owner of that crazy L series says L16. As long as the bore is large enough to accomodate those big valves.
Imagine the potential of a lighter and revvier L series instead of a Ka24 but with better breathing potential.
A toyota 4ag has 2 factory 28 or 29mm inlet valves and the ka24 2 factory 34mm inlets!
The potential is mindboggling no.
Valve sizes of popular twin cams modern 4 cylinder 16 valve engines from factory!-
The grand champion is the 34.6mm - of Peugeot`s Mi16 (36.5mm possible with small 84mm bore!!!) so the ka24 is very close at 34mm and most engines cannot go larger than 32mm such as the 4age.
26mm - Ford 1600 Zetec
27.7mm - Rover 1800 K series
28mm - Toyota 4age
32mm - Ford 1800-2000 Zetec
32mm - VW Golf GTI
34mm - Nissans ka24
???mm - Nissan Ca18
???mm - Nissan SR20
???mm - Nissan QR25
Can anyone add where the ??? are?