I'm working on it - got the badge on the back that says "HYBRID" all I have to do now is to convince the DVLA. What could possibly go wrong?
A 485 engine, compared to a 420 engine, has high compression pistons, more aggressive cams, ported head, roller barrel throttles and 8500 rev limit to get to the power plus the usual bits to help it stay together.
Caterham don't seem to offer upgrades to get a 420 to 485 or old R500D spec. Is it an emissions thing or something? Or maybe just too expensive to be viable ... I would have thought there'd be a market to get to the ultimate NA setup - wasn't really attracted to the 620 with the supercharger.
If your going spend that money then you can choice a better cam to, A well respected master of the dyno had several R500D visit and not a single one made the claimed 263BHP
Must admit I went the same way for a pokey NA 2.0 Duratec - simply a fantastic motor and arguable the best engine for a 7