hi,
the engine had "just been refreshed" according to the previous owner, and on stripping it i can see he was telling the truth, sadly whoever had done it was a twat, and had miss-timed the exhaust cam by a smidge (kent "race" cams with adjustable sprockets) so the pistons been ever so slightly kissing the exhaust valves across the board, cue 13500rpm and it ripped two exhaust valves apart, mangled the piston and lightly scored the bore right at the top (dead quick clutch hand me!)
so anyway, the head has been sorted with 3 new valve seats inserted, valve guides sorted, 4 new valves, all 16 valves/seats re-cut and lapped in nicely (head had already been ported and valve guides cut back)
cylinders have been *lightly* honed and hopefully my new piston arrives in the morning so i can put it all back together.
conrods are already lightened/balanced as is the crank
I'd love to bore it out to a 69mm bore (654cc) but cant afford too many £110+ vat pistons at present !! lol not on top of the head-work anyway, besides everything else in there is new, the other 3 pistons/bores/rings etc etc all look like new.. shame he got the cam timing wrong really..
what i was really wondering i guess is whether the JE pistons would be providing a higher CR than stock and if i'd notice a drop in performance by shoving stock pistons in across the board in the event that i couldnt either source or afford a matching replacement.
as it turns out they do increase compression to around 13.5:1 (depending on block height/head skim) so yeh, i'd have lost maybe 5-6 bhp across the range which, given that once upon a time before someone meddled with it it was pushing around 115rwbhp would not of been a *good* thing
it would infact have been a complete waste of the rest of the nice bits in there.
