Mateingfaces between cylinder and head 3,2 engine

[Torsc]

I am undertaking a full rebuild on my 3,2 engine. I find it peculiar that there is no head gasket between the cylinder top and the head. But I belive the Porsche engineers found god enough.
My problem is that I have had a little leak between the cylinder and the cylinder head. After I have cleaned my cylinders and cylinder heads I can see at some plases some small wounds in the matingfaces. I guess that I have to bring the parts to a mashineshop for levelling.
I got this idea that I should place a gasket between the cylinder and cylinderhead, e.g. a glowed copper ring placed in a groove machined in the cylinder upper matingface. My cylinders and pistons are made by Mahle.

Anybody who has experience with both levelling and installing head gasket on a 3,2 engine.

[Henry Schmidt]

There is no need for head gaskets. Have your heads and cylinders resurfaced and install Supertec Heads stud kit and your problem will be solved.
We can resurface your heads and cylinders.

[Jeff Alton]

As usual, Henry has given good advice. You may have to compensate for the materinal removed from the heads with a thicker base gasket.

Jeff

[Torsc]

Thanks both of you.
As I live in Trondheim, Norway there is not any machine shop that has much experience with resurfacing on Porsche engines. I will take them to a machine shop where I can watch the process. I am aware of that you must remove the same amount on each side.
I am also aware of that there is copper gaskets of both 0,5 og 0,25 mm thickness. I guess that the standard ones are 0,25 mm. That leaves me with maksimum 0,25 mm to remove.

Anyone who has an anvice how to set up the head and cylinder when performing the resurfacing? For the heads I guess one way is to remove the studs that connects the head to the camshaft housing and clamp it down. Will that work or is there a better way?
I am not sure how to do it with the cylinder. Maybe make a "dummy" case and place the cylinder in it and then clamp it down to the desk. I hope you understand what I mean. I am lost for the right expressions in english.

[Jeff Alton]

On mine, the shop removed about .19mm. You can also stack a couple of gaskets if you need more clearance.

Jeff

[Henry Schmidt]

Originally posted by Torsc

Anyone who has an anvice how to set up the head and cylinder when performing the resurfacing? For the heads I guess one way is to remove the studs that connects the head to the camshaft housing and clamp it down. Will that work or is there a better way?
I am not sure how to do it with the cylinder. Maybe make a "dummy" case and place the cylinder in it and then clamp it down to the desk. I hope you understand what I mean. I am lost for the right expressions in english.

Here are the tools we fabricated the perform the jobs you need. Make sure you use a lathe to perform these tasks. A mill will not do a proper job.

[Torsc]

Thanks for your photos Henry. I am not sure that I understand how to perform these thasks.
I am not sure how to install the heads to the lathe. As Henry showes on the photo there is the mathingface between the head and camshaft housing that is been machined here. I am going to resurface the mathingface between the head and cylinder. I guess that it will be difficult to mount the head in exact center if I am going to use a lathe. Is it not easyer to use a mill to perform that task? Do you have a picture of the setup when resurfacing the mathingface on the face that meets the top of the cylinder?

Likevise I do not understand the setup for the cylinder. I understand that the cylinder is put on to the tool and clampt down with the cover. But I guss you then will cover the inner part of the mathingface that will meet the head. Do you have a picture that shows the cylinder installed? I understand that it is possible to use the tools fabricated to resurface the bottom end of the cylinder. Am I missing something here?
I am appreciating all advices.

[john walker's workshop]

here's my rig. it's a copy i made from the factory tool. the head bolts up to the tool in the chuck, and the disc in my hand centers in the tailstock spindle which is moved up to the head and slips into the counterbore for the cylinder for centering purposes before the head is fully tightened to the tool.

[john walker's workshop]

henry, how do you true the top of the cylinder in that setup? the tool appears to overlap the top surface to clamp it tight.

[john walker's workshop]

bump

[Henry Schmidt]

Originally posted by john walker's workshop
henry, how do you true the top of the cylinder in that setup? the tool appears to overlap the top surface to clamp it tight.

Good eye John.
The picture has the wrong cap. The cap for this repair has a taper where it fits in the cylinder.
We also use a full sleve incert that supports the cylinders full length.

[garibaldi]

If you use a taper that fits into the top of the cylinder, and then tighten it down so the taper acts as a wedge to hold the cylinder, then won't this spread out the top of the bore and tip the mating surface outwards?We have found that The aluminum cylinders are pretty flexible.

Using an aluminum biscut to fit into the step in the head for centering purposes may not ensure a concentric cut. Most of the heads I have done have that step oval by a number of thousanths, they seem to have a temdencey to warp outwards on the hotter side of the head.

Do not limit yourself to using one peice of equipment to do a particular job, a mill can be used to resurface the heads and can be repeatable within tenths and offers more control for the operation.

[garibaldi]

Here is an example of a head resurfaced on a mill. These were done special with a groove incorparated for a sealing ring, so if you are wondering why there is a break in the center of the mating surface that is why.

[john walker's workshop]

the aluminum biscuit simplifies the centering of the head, and the head still may need to be tapped to one side or the other to nicely center it. the outer step in the head isn't particularly important anyway, so if it's out a couple of thou, so what.

[garibaldi]

I have found that area to be very critical in sealing and posistioning of the cylinder barrel. Like I mentioned, this head was machined for a sealing ring, so it is absolutely imperative to get the head concentric, otherwise, the ring grooves will not match up. I have always dialed in the heads to get them centered before cutting them.

[vichang4]

Back to the original question, the factory did use a head gasket on the C2 turbos. I would guess for a better seal. I have also seen the C2 gaskets used on high compression engines, and I used them on my 3.4 turbo rebuild. (3.3 turbo upgraded with RUF 3.4 p & c) It is probably a better answer than the O-ring that Porsche abandoned inthe late 70's.
But these are high compression or turbo engines. A basically stock 3.2 does not need these mods.

[Glenn Yee]

Tor,

Whoa, whoa, whoa. Before you go jumping off the deep end, call Ollies's Automotive in California 714 558-7334 and talk to Ike. They are perhaps one of the best kept secrets around. For years, they have been doing much of the machine work for ANDIAL and Porsche Motorsports North America. That means their work has gone to and won every major race in America as well as Le Mans. They will tell you the right way, you do it how you want.

Good Luck

Glenn Yee Motorsports, LLC

[Henry Schmidt]

Originally posted by Glenn Yee
Tor,

Whoa, whoa, whoa. Before you go jumping off the deep end, call Ollies's Automotive in California 714 558-7334 and talk to Ike. They are perhaps one of the best kept secrets around. For years, they have been doing much of the machine work for ANDIAL and Porsche Motorsports North America. That means their work has gone to and won every major race in America as well as Le Mans. They will tell you the right way, you do it how you want.

Good Luck

Glenn Yee Motorsports, LLC

We have all used Ollies in the past and have moved on to other options. Some of us can't wait 6 weeks for a valve job and other simple work.

[garibaldi]

.

[Henry Schmidt]

This set of twin plug, polished chamber heads were properly machined as per Porsche factory on a lathe not a mill. Although we have a quality mill, it is our understanding that the lathe process is for more accurate.