FixedWing

Nice ... thank you!

Stephen

Miles965uk

Great post PHD!
All this stuff is priceless really. But my thoughts tho- does anyone run any Porsche Engine rebulding workshops? If not i think it would be a success. You pay for a whole week or weekends to go and learn about the whole process. would be great fun. and i think alot of people would crave that as its so specialist.
Cheers
Miles

PorschePhD

Miles, we are planning on classes when we move to the new building in Dec.

Miles965uk

Cool, shame im not living in the states. One day i might!

sqlb

Your awesome. I feel like I'm watching an artist at work. If I may I would like to ask you a question. I currently have a 03 Carrera C2. I am interested in acquiring a 993 based TT as a 2nd Porsche. My question is and I know I maybe be generalizing here, How reliable are the 993 based TT? and is there a particular model year I should watch for? I'm interest in a 97 993 TT. Thanks so much! Keep it up. Your postings are very informative.

m42racer

I always thought assembling those engines would be something. Can't quite see from the pic's but the Ring compressor ring is held on the Piston how. I sse you use that factory tool to compress the rings and ring, but how is the ring held onto the Piston. Is there some sort of fasterner or is it just from tension. A close up pic would be great.

What was the intent of this work. Rods and Pump?

Thanks for the photo's. They are very informative.

PorschePhD

M24,
The ring band? There is a latch in the center of it that will allow it to stay together. Once the unit it slid off by the cylinder the latch can be pressed on and separated. At that point the spacers allow just enough room to pull the band out. There are edges all the way around it that catch the liner as it is pushed in. I will see if I can get a pic tonight for you. The tool under all of them positions the gap off of the top of piston.

The purpose was trifold...To know how well at these levels things were holding up which was a no brainer to drop rods in it. I am not done cranking up the power, add better fasteners and update the pump while I was there. So several things were in mind.

PorschePhD

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.

PorschePhD

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….

BC

Beautiful.

Wish we had that damn cam-timing tool for the 928.

John Veninger

So that's what a 6cyl. looks like!

Cool pictures

FixedWing

Nice Stephen. Thank you!

One question for you ... when you rebuild an engine like this, which parts will you always replace and which parts will you normally reuse?

Stephen

Deb

I forgot to install those elastic bands as in the pics - oh well I'll just tear it down to-morrow morning, stick some new bands in and be in time for my 2:00 PM appointment. It takes me that long to open the hood!!
Great pics and description - - Thanks!

BC

I can honestly say that it really looks specialized enough for the money some 996 tuners charge. And I thought the 928 looked complex the first time I cracked it open.

PorschePhD

Normally when I redo an engine things like seals, bearings, chains, ramps, circlips, rings, guides, seats, sometimes valves. The head work all depends on the condition. Other items that move or wear and are not in the category of cams (as long as the condition is good) get replaced. IN regards to major components and replacing, it depends on the goal. If you say I want "XXX" power then that too will steer the course of replacement. For a normal clean up job though the things listed above are a normal day.


Hey John!! Nice to see you slumming over here!


Hey the rubber bands are factory

What we do is not for everyone. No doubt about it. I do believe there are a lot of people building motors, but building something and having it run and building it and having it right are two different things. It never stops amazing the crap I see in the industry. AND IT RUNS!