JC in NY

I would like to gather some information regarding the cylinder head leak fix.

1. Assuming one can DIY the disassembly of the engine is it possible to do some machining of the case and or cylinder barrels to achieve the proper sealing surface? (This is instead of buying a new set of pistons/cylinders).

2. What machine shops currently do this work? What is the approximate cost? What parts need to be send to them to have this fix done? What is the turnaround time?

3. What other updates can be performed at this time to the case/cylinders while it's all apart?

Kevin

JC

I would recommend you calling Ollie's @ (714)558-7334, or German Precision (408)747-0728, they can fix you up. It is not needed to split your case unless you have had stud problems and your cylinders have pounded out the seating surface of your case. I would purchase ARP or Raceware cylinder head studs and rod bolts.

Bill Wagner

JC:

To answer your questions by number:

1. and 2. Yes, re-machining the heads can be done and I don't believe it's considered to be an unusual fix. When I was looking into buying a Porsche, I checked out the local prices for various fixes for a leaking cylinder head. Local shops that did the full cylinder replacement, gaskets, etc. seemed to throw numbers like $6000-$8000 for the job out. I THINK I recall the numbers for remachining the heads being $2500-$3500 (and that's with the shop doing all the work). I have no idea how much a machine shop would charge to do the machining, or what specs they use. I have no experience with how well the re-machining process works, or how well it holds up over time. You would need to talk to someone who's had it done and see how well it works for them. I don't believe re-machining the heads is considered a Porsche approved repair. Talk to some local shops that are familiar with this process. It might be cheaper to consider looking for a 964 engine out of a wrecked car with relatively low miles and the cylinder head updates already installed (it started during the 1991 production run and will be in all 92+ cars). You could also try a 993 motor

3. You could go with a full 3.8 L bore and updated cams....now you're talking REAL money!

Good Luck,

Bill Wagner

Adrian

Dear Jon,
The Porsche approved repair is to install a head gasket (metal one now), replace the pistons and cylinders and machine the heads with a groove. The current cost in the USA (Thanks Bill G) for the piston and cylinder kit is around $2,900. I am informed that no more than 30 hours total labour charge is required to do this repair. Obviously additonal work means additional expense,
Ciao,
Adrian
911C4

PS: If you take the 964 to an approved shop you MAY!! be able to negotiate the price down because this was once a warranty repair. This will be up to your negotiating skills. No hope at non approved facilities.

JC in NY

Followup for those interested:

I called Ollie's. The fix that they perform involves machining the heads and cylinders to allow for the use of a 935 style head gasket. The total cost including the gaskets was quoted at $650. You send them your heads and cylinders; the turnaround is around 10 days.

According to Ollie's this was the approved Porsche fix until they invented the new cylinders.

Kevin

JC;

I have 2 friends that have that 935 conversion done to previous 964's they owned. It is a very good alternative. If you install raceware studs I would think that this would never have this problem again. The next cheaper alternative is to buy a good set of 993 P & L with heads. There was an individual selling them on this forum a few days ago. Good Luck

Bill Wagner

Adrian:

I find your claim that the engine updates can be done in 30 hours to be a WEEEE bit on the optimistic side. Does this include the time/labor for re-machining?

Everyone else:

The prices I quoted were for shops to do ALL the work, not just machining.

Just Curious

Bill Wagner

Adrian

Dear Bill,
These are the Porsche recommended times to carry out the removal, disassembly fo the required areas only, repair, installation of new parts, reassembly and re-installation. The times are also showing up in receipts that I have received from various owners who have had this work done. Remember this is just the repair, "Nothing Else",
Ciao,
Adrian
911C4