Heads remachined - 964, one out of spec!

[njansenv]

Hello, all of you! I'm slowly working through a reseal/top end rebuild on my 964, and discovered that one of the heads measures 83.67mm. The other heads measure 84.23.

Now, I need to work with the head rebuilder to come to a solution: the spec is for a minimum of 84.28 +-.02. I'm really only concerned about the single head. I suspect the rebuilder will want to take all the heads to 83.67, and I'm worried about the implications. I "believe" I can take about 0.6mm off the chain housing to ensure cam seal integrity, but what are the risks?

Here in Australia, heads are unobtanium - I'd have to buy used heads of unknown origin from out of country and have them rebuilt, and I'm dreading the cost and headache if I need to go that route.

HELP!!

[Trackrash]

I'm no expert on the 3,6s but;

Did you have any problems with the heads sealing on that side? Has the motor been rebuilt before? Is there evidence that the heads have been previously surfaced?

Did the cam turn freely?

What about the base gaskets. Not sure if your motor had them, but could the cylinder on that head been shimmed?

[njansenv]

I should've been a bit clearer: my heads have been rebuilt, and one was accidentally skimmed significantly more than the others. I don't believe that the motor was opened up previously, but don't have any of the cars history. The cam binds badly as I tighten things up, and I'm not aware of any shimming that I can do on the barrel of the 3.6, though I'd certainly be open to that if it's a possibility!

Cheers,
Nathan

[mikedsilva]

****
so your machinist took too much off one of the heads?
Sounds like he needs to find another head.
You don't want to skim them all, since it means that they may not be usable for the next time they need to be reuilt.

I am sure you can find another head from the same group on ebay or this forum....

By the way, where in aus are you?

[Henry Schmidt]

Try Ken @ 911 Vintage parts for a single replacement.
info@911vinatgeparts.com
or 911vinatgeparts@earthlink.net

[faapgar]

Hi,in a pinch you could always use one of the head gasket repair rings.930-104-381-01.They are 0.5 mm thick.Fred

[Matt Monson]

What Henry said. But a core head and make the machinist prep it free of charge.