While we're discussing the elusive ideal state of tune, can I ask other forum members what continuous engine rev's they expect from an engine running a sports cam (356 or 357) on open roads and what sort of speeds they expect to
cruise at? (assume large journal motor in reasonable state)
While my track engine happily sits on 6000+ for periods of around 8 minutes but that is not the same as sitting on the highway or open road for half an hour or four. It also has a six speed so is never allowed below 4000 unless I'm warming down, in fact 5000 is my change down point.
Just pondering my gearing on my 356 road rocket build. the gearing (19T rear, 1:2 Primary) I have equates to 18mph per 1000rpm which seems fine : 3-4000 being 54mph to 72mph which sounds like a good all day gearing. I could buy new gearbox sprockets to get 19mph or 20mph per 1000rpm but suspect the later makes top gear on a 4 STD speed bike a bit of an overdrive and doubt the middle option (20T gearbox) gives me sufficient benefit over what I've already got. I'm thinking practically a 3500-4500 range can be retained all day but ideally 3500-4000 for cruising in top and 3rd for passing and with that existing gearing the old imperial ton is 5500rpm which sounds feasible
Our north island NZ roads are typically hilly, twisty and poorly surfaced, no real motorways.
