My new 98mm Ps&Cs from Supertec

[sand_man]

Here's a couple of pictures of my new pistons and cylinders. The pistons are custom 98mm JEs and the cylinders are the new ones that are made for Henry Schmidt...I think they are QSC. These things look too pretty to use.

Henry,
On that large sealing ring (head gasket) is there any type of groove that needs to be cut into the receiving end of the cylinder head? Any special instructions? Any special deck height adjustments that need to be made for it? Also, on the pistons do you think I'll have any clearance issues using higher lift SC cams? You probably won't be able to answer that one as we won't really know until I do the check.

[supchg911]

Hey sand man,
I just installed a set of 98's with JE pistons too, but on my '89 there are no head gaskets. Was that head gasket always there was that done by Supertec?

[sand_man]

These are evidentally a "new" cylinder that are being made exclusively for Supertec. Honestly, I had no idea about the gasket until the order arrived. I just don't want to screw anything up. If something needs to be machined, now is the time.

[supchg911]

I'll be interested in hearing from Henry too since this may be a problem area that is being addressed on these engines.

[sand_man]

I think it might be somewhat derivative of a "Nirosist" sealing system. However, that typically involves cutting a groove in the head. I don't wan't to speak for Henry though. All I can say is they look first rate!

[jpnovak]

I suspect these are marketed toward an SC owner that already has the cylinder gasket. I am sure Henry will chime in with a correction.

[supchg911]

I guess I assumed that these were from sand man's '87 930. Probably are from an SC. Whew, thought I forgot something when I put mine together last weekend!

[88-diamondblue]

They are a copper sealing ring from earlier Porsche design. I am going to be ordering mine soon. I'm sure Henry will chime in and explain more. I'm jealous that I don't have them yet..

[sand_man]

I hope they're compatable with a turbo environment...

[Henry Schmidt]

The cylinders are designed to install as they are. The additional machining.
The cylinder was an extension of two different designs.
The early sealing CE ring used by Porsche in the early Nikasil cylinders and the graphite gasket of the 964. We were looking the seal the cylinder better than both and weren't happy with no gasket at all.
We were using Nirosist sealing rings and noticed that they leak almost as bad as using nothing.
These gaskets when used with Supertec head studs show no movement or leaking under the most severe conditions.

Welcome to a new era of Porsche performance.

[sand_man]

EXCELLENT! Anything special I need to know about torque values? Can they be torqued more than once? For instance can I torque them in a "dry assembly mode" to check for clearances and then break them down and perform final assembly, or will this ruin the crush properties of the copper ring?

[Henry Schmidt]

They can torque them over and over until heated. When they heat with engine temperature they take a set. After the engine has been run we like to replace them.
This does not mean you have to replace them after a certain mileage, it means that on the next rebuilt replace the gaskets.
On turbo applications we torque the Supertec head studs to 32lb.
Consult other manufacturers for their recommendations.

[Henry Schmidt]

Originally posted by sand_man
I hope they're compatable with a turbo environment...

These cylinders were specifically designed for turbo application.
Turbo cylinder pressures facilitate the need for additional sealing and quality head studs.
In the 91 Porsche turbo, you will find steel head gaskets and we quite often see them deforming from heat and creating a leak that may not have form if not for the gasket.
We have not seen this with our cylinders.

[starlifter1]

How much are they? I will be needing a set for a SC to make a 10.5 to 1 3.2 SS

[Henry Schmidt]

Check Ebay
Who knows? you might get lucky

http://motors.search.ebay.com/_W0QQsassZsupertec911

[village idiot]

Wow!! the price is very reasonable too.
Henry, are there any plans to market different compression ratios through your company or would I have to buy the cylinders from you and contact JE for a shelf/custom piston??

[Henry Schmidt]

84mm, 86mm, 90mm, 92mm, 95mm, 98mm, 100mm, 102mm
Any compression ratio you choose.

[village idiot]

Originally posted by Henry Schmidt
84mm, 86mm, 90mm, 92mm, 95mm, 98mm, 100mm, 102mm
Any compression ratio you choose.

Nice! time to start budgeting
Do the cases on my 78SC need to be bored to fit the 98's??

[crashmy911]

Yes I would like to know this also?

[Alan.UK]

Those valve pockets look similar to the 98mm Max Moritz set up which will only run a relatively mild cam, unless additional clearance is made.



I ended up buying new a B&P set for my SC motor. 98mm J&E 10.3.1 CR with new barrels from Perfect Bore, here in the UK. These will be running S cams.



Alan.UK