7 replies to this topic

[Chappb]

I have cylinder head which i was given in part ex for some other bits and i was told that it is a Metro Turbo head. How do i know whether it is or not? It only has valve guides in the head with no valves.....
Thanks for any help

[mossy2a]

the exhausts valves have a thicker stem.  I've got 8mm in my head..  thus the guides bores will reflect this.

[Turbo Phil]

As above, if it has ex guides with 8mm holes then it's a Turbo head.

Phil.

[Chappb]

Thanks guys i'll check!!

[Chappb]

Is it possible that the valve guides could have been replaced with some with a smaller stem diameter over time? As they all measure 7mm but the bypass hole has a flat blade screw blocking it which im led to believe is what turbo heads had?

[gazza82]

They could and someone could have plugged the bypass too.

[wile e coyote]

Yep it's possible .......turbo heads are in essence regular valve sized '940s  but the turbo had sodium (I think) valve guides to keep things cool... necessitating the thicker valve stems on the exhausts.- you should be able to tell if the guides are there...... I've a kosher unmolested (and never run on UL) turbo head if you're specifically after one?

[Turbo Phil]

At the end of the day it doesn't really matter if it's a Turbo head or not. They're essentially the same as any other small valve 940 and can be modified in the same way as other castings.

Phil.