Engine failure on track day, need some help, T4 GB 2.0 head failure Options

[CheeRS]

Hi, here is my presentation post :

http://www.914world.com/bbs2/index.php?showtopic=337989

two weeks ago I was in Monthlery near Paris France, for a wagenfest with my 914.

Get some troubles with the engine, a hammer noise and the engine stopped smoothly like out of gas.

here is what I found :
https://drive.google.com/open?id=1gzsWwNBOh...86Kbof2P4BCHHrm

some pics

[Dave_Darling]

We would call those "cracks", not "scratches".

If the cracks get into precisely machined areas, like where the cam and the crank run, the case is junk. If it is important to have that specific case with that specific serial number, a really good machinist can probably cut out the cracks and weld them up, then re-machine everything so it is in spec again.

If the cracks do not run into those areas, there's a very good chance that they will spread into those areas. Again, a very good machinist may be able to drill the ends of the cracks and stabilize everything, but that is probably not going to be a permanent solution.

The damage looks to be around the lifter holes. I would be the most concerned about the camshaft bores, because having one of those move will kill the motor pretty quickly. I wonder if that could be related to the "Type IV Syndrome", where someone over-tightens the nut holding the sump plate onto the bottom of the motor? This can bend one of the through-bolts that the oil pickup hangs from, and crack the case around it. Distressingly common.

If you have access to another case, I would suggest using it. That's the simplest way to move forward. If you do not, either find one or find a really good machinist who can weld and machine the existing case.

--DD