evounder

Im wondering if anyone has converted there cylinders to accept head gaskets, i heard the cylinders can crack when doing so, im just looking for everyones input on that?thanks

wellcraft290

My car was done before I purchased it. I believe there is a kit and a good machine shop could do it. No issues here for 13,000 miles.

darth

My opinion of the gasketless seal is that it is as good if not better seal than one can get with a gasket. The trick is to keep the heads torqued to the correct value as the expansion contraction of the aluminum heads and cylinders is quite large and tend to loosen the head bolts. I've had experience testing devices which were subjected to extreme pressures upwards of 5000psi and the only way to achieve a good seal was to have a 0 clearance metal to metal seal. The gasket is just a band aid solution to compensate for this expansion/contraction and eventual opening up of this interface.

Just my $0.02 worth
Bill

Steve Weiner-Rennsport Systems

We've done quite a number of those with successful outcomes for several years,....

Basically, the heads are machined to accept 993 sealing rings and the tops of the cylinders are trued and machined with a very slight bevel that wedges into the sealing rings when the heads are torqued properly.

It works very nicely and saves buying a new set of P/C's when the existing parts are perfectly serviceable.

jsoderbe

Hi guys,

As always excellent advice here. I have a set of 1990 heads and cylinders measured to be in very good shape, but which suffered from severe blowby.....

So I am lifting this thread to ask if someone has any specifications I can take to the machine shop here in Sweden?


Regards,

Johan

jsoderbe

Anyone?

Earlydays

It was an update performed by Porsche......a local dealer should be able to pull-up the technical bulletin on their computer and give you the milling specs

FeralComprehension

Here's the TSB.