Ok gang, here is the meat of the motor. The whole system comes together through the heads and cams. There are a few pictures I left out previously so I will back track a bit and show those. Below is a picture of the old style 993 chain housing gaskets. The right side only will need to be profiled to move around the cylinder block. A little file will do the trick.



Once you have the head on, the gaskets and the chain housing you can then set the cam assembly and the gasket. Notice the lettering on the gasket. There is an orinetaion to the gaskets, They are embossed on one side and different on the other. The EGR ports run through these and are sealed specficly based on shape by the seal. Any seal in the car that is sandwiched will say “top” which mean you should have this on the front
.

Cam housing installed.


Next install chain ramps and bolts. Notice that the bolts are all the same size but one. On each chain housing there is a short bolt. This bolt goes on the outer most section of the chain housing. If you try to use the longer ones the bolt will bottom out and in crease the risk of cracking or popping a hole in the chain housing.



Next install the tappet. Each one should have been marked prior to disassembly and be bank specific. The tappets can only go in one way and must be lightly oiled. Per Porsche do not oil the cam journals. Note the pin on the lower right hand corner of the tappet to guide the unit in and prevent spinning.


Next is to ready the cams. Oil the lobs and press the oil tubes on the end. There is a tube for the left and right banks to accommodate the offset from the right to left bank. Much like the older cam sprocket issue. The oil tube on the left is for banks 1-3 and the one on the right is for 4-6. There are rings as pictured below that must be pressed on to the nose of the cam. This is done by hand and without tools.

Cam end with ring


Inlet Cam with tube pressed on.



Pre lube the cam jornels and cam saddles.


Insert cam saddles. Take care in observing the order of the saddle to the housing. Each saddle is marked or hand engraved from the factory. Match the face of the number with the number on the saddle. Tighten per Porsches specs at a half turn each in the correct order then tighten 9.5 Ft Lbs. The order is important here. If you screw up here you will destroy the cam on start up.

 

Cams in saddles. One note. Before you place the inlet cam on and secure the saddles make sure that the chain is over the top of the cam. Once the cam is in the saddle rotate the left bank so that 1 intake and exhaust lobe face one another. One 4-6 make sure they are opposite and go away from one another. The picture below is cylinder 1.

 

If not the chain sprocket and chain can not be put on. Once the cam is tighten down you may put the inlet sprocket on and the exhaust sprocket in. Only hand tighten the bolts at this time. The left and right exhaust sprockets are different and are market on the face
Left sprocket “links” I think is left in german.


Right sprocket. Notice the offset


Next set tension on the chains by inserting the factory tension tool.


Set the unit tension until the first mark just disappears







Next setup a dial gauge to mark true TPC. The point of this is to watch the gauge as you come up on TDC. When that happens the gauge will briefly stop moving. There is a point where the gauge will swing up then come back down when the piston comes back down. That spot in between the two is TDC. The plunger is extended down on to the top of the piston.




Set factory cam tool for left and right on the back of the cam. Note the order in which it is bolted up.


Making sure you are on TDC and insert the tool in the back of the cam. The tool will only go in one way. If it will not slightly rotate came until it slips in via the nut built into the cam. Do this both with the inlet and exhaust.

 

Turn center of the inlet sprockets to the left stop and lock inlet and exhaust cams while using the holder tools 22 ft lbs. Remove the tools from the end of the cams and lock the top inlet bolt by rotating 170 Degrees. The bottom sprocket will be rotated 90 degrees. Remove tools and rotate 720 degrees and check TDC. Insert factory cam tool and confirm timing is still correct for left bank. Rotate engine 360 degrees and duplicate order to the right bank.

Looks like where we started….

 

Damn do I love this. Awesome Stephan!

 

Now I feel the urge to tear down my engine and putting it back together just for the heck of it. If I mess up, and I feel that I will being that I am not engine-savvy at all, I will ship the parts over to you and you can ship me this one seeing that it's nearly ready.
All kidding aside, Stephen, this is a prime example of what makes these forums great. You are definitely a master of what you do.

 

Thank you Stephan, this is informative and fun at the same time.

 

Wish you had taken time lapsed photos of the whole process and compress them into a video

It's highly informative and entertaining. Think I'll print and frame some of the photos.

 

My dream of being able to tear apart a Porsche motor and rebuild it has just been shattered!!! That is some serious mechanical wizardry going on there... :-)

 

A video would have been cool, but this got built after I was done for the day. Some day I may do one, but it chews up a lot of time even shooting pictures. Besides I am not sure that some of the talking I do to myself would be appropriate for the video

 

The sad thing is the pictures make it look rather easy. There are a lot of things you can't see because pictures don't sow it. There is always a specific order and a route that has to be followed. There are some pitfalls that if you don't do one thing then you end up having to restart and cost your self another half an hour. Things like this are hard to explain or know without doing motors. Lots claim they do them, few do

 

996tt motors, Very few as of this date.

 

I think most are unfamiliar with the amount of tools that have to be bought.

 

That's okay. You can have a "Day in a life of a 996TT motor build: Uncensored" video

You can show all the rampage and cussing you want

 

Ok...now how much $$ for this rebuild???