2.0 Head Gasket delete? Options

[torakki]

I've read where it's a good idea to remove the head gaskets and re-assemble without them. Something about, they crush and cause an issue. Is there anything else you need to do or change, in their place? Like a different head design?
Thanks

[rick 918-S]

Question:

The update states improvements were made but does not say what they were unless I missed it in my speed read. What was done to accommodate the change?

[Superhawk996]

Question:

The update states improvements were made but does not say what they were unless I missed it in my speed read. What was done to accommodate the change?

Re-read, the stated actions are the improvements.

[rick 918-S]

Question:

The update states improvements were made but does not say what they were unless I missed it in my speed read. What was done to accommodate the change?

Re-read, the stated actions are the improvements.

I re-read the stated actions. Just because the bulletin does not list the type IV does not mean it would not benefit from the upgrade as well. I was thinking there was some sort of a metallurgic change that our type IV's don't have therefore would be a negative if you tried it.

Type IV rods can be notched, Cylinders can be honed out for increased clearance, and the shims can take the place of the base gasket. Don't see the problem.

[Superhawk996]

Type IV rods can be notched, Cylinders can be honed out for increased clearance, and the shims can take the place of the base gasket. Don't see the problem.

I tend to agree.

With respect to pistons: modern hypereutectic pistons will have their own special piston to cylinder clearances that will be determined by the piston suppliers. Forged pistons will have their own larger clearances vs hypereutectic so that #1 action on the bulletin can be taken with a grain of salt.

The other actions in the bulletin are focused on increasing heat transfer. First by the poor man’s oil squirter (notched Con-Rods) to get heat out of pistons and into the cylinder walls. Second, by eliminating the insulating effect of the cylinder base gasket ( paper) which gets changed to aluminum (due to thickness) but also because the aluminum allows better heat transfer from the cylinder into the case. Finally, by elimination of the head gasket so that the cylinder has a better heat transfer to the head.

With respect to cylinder to head sealing, Wonki nailed it. All the VW air cooled engines seal rather poorly when cold. When they come up to operating temperature they seal much better. Why?

The difference in thermal expansion is why. Aluminum is expanding much faster than the cast iron cylinders and the steel head bolts. As the head dimension grows but the steel studs grow much slower. This means, you get increased sealing the hotter things get up until studs break or pull out of the case (2.7L 911 sound familiar - cough - cough (IMG:style_emoticons/default/rolleyes.gif) ) ever notice how Nickies (aluminum cylinders) require the use of (stronger) ARP head studs instead of OEM head studs. There you go.

Final thought: how many here have a Dyno and have done the development work & testing to argue this further than mere personal opinion or based on the results of onesie, twosie, engine builds with limited mileage accumulation? Gonna’ roll with Mr Raby on this one.

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