valve clearance's, how important

as some may remember, i managed to drop the shims and buckets out of my head, have put them back in, measured removed measured removed.

and after a lot of brain crunching nearly all of them are ok, there are just a few that are escaping me, on one the tolerence is 0.010 and the space is 0.015. and there are a few that are very marginally out,

do i need to get back out there and do some more maths?

if there out by that much you may get away with it but i would recomend trying to get them all within tolerance mate.

tolerances are there for a reason.

i'd get em all within tolerance if I were you whilst its in pieces

where do u find out the clearances?

what on the head? or what the tolerances are?

exhaust valve's - 0.012 inches - 0.016 inches
intake 0.006 inches - 0.010 inches

good luck with the messuring dude! hate fiddly jobs!

SiCaln said:

where do u find out the clearances?

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the clearances are the same used on the 4efe engines, and can be found in the corrolla haynes manual

monka said:

what on the head? or what the tolerances are?

exhaust valve's - 0.012 inches - 0.016 inches
intake 0.006 inches - 0.010 inches

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get them within what the tolerances are.

Nwimie said:

good luck with the messuring dude! hate fiddly jobs!

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fiddly jobs? try doing putting the valve retaining clips in at 11pm at night, after working for 12 hours, how the hell i didnt pick the head up and through it accross the garage i dont know. lol

I'd recommend getting them spot on, or as close as possible. My friend had a gti-r that decided to put a hole into no.3 piston. He had it re-built by a supposed reputable engine specialist, as i havent got the room to tackle a job like that.

After he got it back and took it on the dyno to be set-up, it pulled very well up to 5,000rpm, then went completely lean. He bought it to me and the top end was rattling like mad. The supposed reputable engine builder had got the shims all messed up, and the valve clearences were huge! After spending a fair amount of time measuring and swapping round shims, they were spot on. Another trip to the dyno and the problem was cured, 330bhp at 1.1bar.

Sorry for the essay, just sharing my experiences with bad valve clearences.

kk, cheers mate,

well been a bit bored so i've just gone and remeasured everything again, and i think i have everything worked out.

just 1 odd one, exhaust port gap measured at 0.10, and from what i can work out the shim needs to be from 0.1150 to 0.1110.

its all done guys,

fucking persceverance (spelling?) pays off, all my valve clearances are spot on now. lovely

good to hear , i got the same problem with my head , malplaced shims and clearances , getting real slow after 4-5 rpm ! measuring time !