4AGE camshafts (again)

[Alex170984]

fax0815 Wrote:Not much to add to the info above,
because you´re on the edge of the capability of your stock valvetrain, uprated springs are advised, they´re only around 120quid and worth it, but get the verniers first! Remember your springs have been fitted to an engine for around 20 years, on the 4 AGEs I´ve build they didnt even meet the factory specs.
A ~260° duration with about >8mm lift properly shimmed and dialed in,will keep the engine pulling right to the limiter, rather then creeping out at 6500rpm.

If you ask me, don´t waste money on Apexi SAFC/ Greddy Emanage! (Use the money for good bearings, ARP conrod bolts and decent pistons, cause that will make you a very good base engine, for whatever your plans are in the future) Run the standard ecu for now, tweak the fuel pressure to compensate while you´ve got the air fuel ratio checked out (Every dyno will check/ adjust this for you for 50quid). SAVE the money towards a freedom ECU, like emerald, Omex (that can be mapped by everyone!!!), it will give you a lot more advantages in the future, if you want to go ITB´s, or wilder cams, of course its about a 1k investment, so no ideal for starters, but definatly something you should consider...

Regarding CR ratio and standard ECU, I can guarantee there are no problems, my very first 4AGE, had the head skimmed to the absolute maximum (it wasnt me who did it), litterally one more skim whould have taken material of the valve seats!!! Ran fine When I rebuild it I´ve changed the pistons for the US spec 9,4:1 (iirc?) ratio pistons and remachined the pockets, was lazy back than so didnt bother to calculate static compression, but it must still be fairly high, has done me 20000km in driftdays and still loves it on the stock ecu.
I´ve to admit, it´s allways been on 98 or 100octan fuel.

I have recently checked my valve clearances and they were all within tolerance....