valve clearances

[nemesis 1006]

i need to adjust my valve clearances and iv seen on and old post somewere that it is 15 and 20 but wot way round is it the inlet needs to be ? and the exhaust needs to be ? :scratch::confused: thanks

[Spooky]

inlet is .15 exh is .20...

[nemesis 1006]

spot on cheers for the help m8 :agree::)

[Tony Walker]

Exhaust valve clearance needs to be larger as the exhaust valve absorbs more heat, and expands more.

[modfather]

i just had a look in the haynes manual and it says inlet 0.20 and exhaust is 0.25

[Kris M]

the haynes it wrong :D

[HULK]

Anyone know what the clearences are for a piper 270 cam. Not even sure if it is a 270 wish I knew for sure :cry:

[turbo ted]

piper 270 cam +285 and standard cam valve clearances are 0.20--o.25 the haynes is right:p

[Spooky]

I've set mine at 0.15/0.20 & 0.20/0.25 on a standard cam before, made no difference whatsoever!

Even set the clearances the same for the inlet and exh on a standard cam @ .20 each, no issues.

Like Ted says and dependant on your tune, the valve difference may need to be altered a little accordingly.

[Tony Walker]

As long as you have some clearance when the valve is closed and the engine is hot its ok. The clearance is to ensure the valve closes properely and isnt held open which would result in a massive loss in compression. too big a gap and the engine will be really tappy and potentially not open the valves enough.

[Spooky]

:agree:

[Mart]

This is getting as regular as the Cup mod Q.

2nd revision Haynes manual is wrong. 1st revision & the gtt owner's handbook both state 0.15mm inlet, 0.20mm exhaust for o.e cam valve clearances.

[turbo ted]

the more you tune it, the more crazy boost you run, the more clearance you need simples:p

[Mart]

Not on a standard cam.