MC Head gasket upgrades?

[Jörgen Karlsson]

> > My head will go on with a stock gasket and M12 12.9 quality
> insex bolts. The
> > torque specs that I recived was 120-140Nm. If i can get nuts
> and studs that
> > fit I will go with them instead.
>
> I've never measured the torque when bolting a head down, but I
> have a feeling it's higher than that.  That has you finishing the
> half-turn from 60Nm at only twice the torque - the memory in my
> hands and arms is that it's more than that.

I know what you mean,but this was the tourque specs that I got. Except that
I left one part out: -Or until it feels good...

> I'd be cautious about using anything other than stock.  If yoiu
> stop the head bolts stretching by brute force and the engine enters
> a condition that would normally cause it to do so, where does all
> the energy go without that safety-valve function?

I wouldn't call it a safety valve, I have a head here that looks like
someone has grinded of a piece between #4 and #5. I don't know if it was an
uneven deck or bad bolts that caused the gasket failiure but it is never
good when a head gasket blows.

The shop I got the recommendation from only works with tuned engines, even
with stock internals the bolts are one of the weakest links. I perfer a rod
or piston failure to a head gasket failure. Both mean that I need to get a
stronger aftermarket part to handle the power I try to pull from the engine.

Jörgen Karlsson
Gothenburg, Sweden.