Need for 0.5mm cylinder base gasket?

[dtxscott]

Going back together with my stock 3.2L. The machine shop removed 10 thousandths/0.25mm off the heads to clean up the cylinder mating surface.

This pulls the cam axis 0.25mm closer to the crank axis. The tensioner boxes were not touched.

It may be a rhetorical question, but I'm looking for some real-world experience on whether to source the 0.5mm cylinder base gasket to recover the .25mm.

It seems that the factory specs of .25mm material removal coupled with the availability of a 0.5mm base gasket are linked.

What is the best way to recover the .25mm of head mat'l removal, or is it necessary?

Thanks again.

[icarp]

What is more important is the squish area for the piston top to the head .
This needs to be .040" , that is the base shim thickness, then the cam box alignment gets processed .
.010" is a lot to clean up heads , .003"-.004" is more like a clean up.
Ian

[dtxscott]

It seems I may have found my answer.

From the Carrera tech spec book, the comment below says to add the 0.5mm gasket when doing the head work.

[faapgar]

I have discussed this several times.When you are at this point you use the factory repair which no one remembers.It is a head gasket that is 0.5mm thick.930-104-381-01.The gasket is made of INCONEL and HAS a high temperature coating on it.I have used these on 930 Turbo motors since 1986.For a Turbo motor works perfectly up to 1.0 bar for 75,000 miles.Ciao Fred

[icarp]

Originally Posted by faapgar

I have discussed this several times.When you are at this point you use the factory repair which no one remembers.It is a head gasket that is 0.5mm thick.930-104-381-01.The gasket is made of INCONEL and HAS a high temperature coating on it.I have used these on 930 Turbo motors since 1986.For a Turbo motor works perfectly up to 1.0 bar for 75,000 miles.Ciao Fred

Thanks Fred, yep I don't remember that fix , but I'm glad to learn it. I still think that the OP needs to address the base gasket thickness and squish clearance . Where do we find the Inconel head gasket these days?
Caio ! Fred
Ian

[dtxscott]

Thanks for the confirmation Fred.

[faapgar]

I bought a set of six from my local dealer 2 weeks ago.List is about $15 apiece.No head leaks anymore.

[reclino]

A photo from Fred's work bench. I bought a set of 6 from Porsche a few weeks ago.
Thanks Fred

[dtxscott]

Interesting. This part doesn't show up on the parts diagram for a 3.2L.

[reclino]

Nope, I think it shows up for the 993.

[Henry Schmidt]

Originally Posted by reclino

Nope, I think it shows up for the 993.

Turbos only....