valve clearances
Turbo Mini Forums

Just wondering if anyone can tell me the valve clearance on a standard 1275 metro turbo engine
I'm new here

Hi rubans, welcome to TM.

Im not sure about what the haynes or autodata say, but I just did a quick search on the site (give it a try :) )and it seems a few people use 12 thou for the inlet, and 15 thou on the exhaust (the exhaust valves need a bit more clearance as the they get hotter and expand).

Im sure you wont have any probs if you use the above.

Jo

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

what about if your using roller tipped rockers, do you still use the same values?

valve clearance is given by the required follower/valvetrain/tappet clearance, which is 10thou. However there is a geomertry concideration to make since you cant measure the clearance/float at the tappet, so instead have to measure it at the valve to valve stem which is on the other side of the rocker for that valve. This means that you have to account for the rocker ratio which is 1.19-1.23:1 on std rockers. Therefore the gap should be set to 12thou or thereabouts for std rockers. If higher ratio rockers are used such as 1.3:1, 1.5:1 or 1.7:1 then the valve clearance should be set accordingly - 13thou, 15thou or 17thou. People seem to air on the side of caution with the exhausts due to expansion, but i dont have the time to calculate how much it'd actually be.

I cant take any credit for whats writen above, its merely repeating something i've read from another source and is therefore up for debate.

Personally i set mine to 13thou accross the board on 1.3:1 rockers, but its niether a turbo engine or a high power unit, but i never had any problems with either excessive noise or ill-effects.

Edited by andeh on 20th Apr, 2006.

I've seen the future and tbh its Pie

Hello to everyone by the way
This is gonna seem like a silly question but which valves are exhaust and which are inlet are they alternate or does it depend on where there are inrelation to the ports?

I personally always set mine to 16thou, regardless of anything.

valves are from as follows:

Exh-inlet-inlet-exh-exh-inlei-inlet-exh.

Wil

Edited by wil_h on 20th Apr, 2006.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph