3,2 engine rebuild

[Torsc]

I am a hobby mechanic living in Trondheim, Norway. I am currently rebuilding my Porsche 911 Carerra 3,2 model 1985 engine. The car have traveld 207 000 km widout any previous rebuild. The engine is going too be rebulid to standard specification.
I have the following books; 101 projects for your Porsche 911, Porsche 911 performance handbook, How to rebuild & modify Porsche 911 engines


I have already dismantled the hole engine. The reason I wanted to rebuild my engine was that particularly cylinder number 5 was leaking. I had also a rough idle on my engine. When I took out the alternator I could see some black substance on the cooling ribs between the cylinder and cylinderhead. This was also visibel at other cylinders sow I guess that there was some kind of leak there. 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 am aware of that the building hights of each cylinder and cylinder head must be the same on each side and prefeably on al cylinders. What I don't know is how much material is there possible to remove. Is it possible to use a thicker copper gasket beneath cylinder? Is it possible to use at 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.

I understand I have to change my headstuds. I have standard steel stud on the intakeside and dilavar studs on the exhaust side. I have been adviced to use the head stud (fully treaded), washer and nuts from a 993 turbo and connecting rod bolts and nuts from a 964 turbo. What is your advice on this?

I have also checked all tolerances and I have found out that I can use standard size main bearings and connecting rod bearings. I will have to cange the coneccting rod bushings, bushings in the rocker arms, valve guides, inlet valves (and also the exhaust valves I guess, they do have a small groove in senter of the head) , piston rings, aluminium intermediate shaft gear (0) and cam chains. Peculiarly I found out that the inlet valves was worn more than the exhaust valves and specialy on the lower part of the valv stem (near the head). I have not taken out the old valvguides yet. Do I have to do that before ordering new ones? Do I need oversize? I will have my machineshop to do this job for me.

I hope someone can give me some advices on my questions.

[ChrisBennet]

I'm surprised that you need to replace the intermediate shaft gear. Was it damaged or does the backlash just seem out of spec?
-Chris

[Torsc]

I have not checked the backlash but the teeths are worn. I can see that the mathingfaces on the aluminium gear have some small depressions. One of the bearings on the intermediate shaft was was worn in to the copper. I had also a strange noise from the engine, a kind of whine so I am going to change it as a precaution. I can't see any damage on the gear on the cranckshaft.