TSB#9404 946 Head Height

[Porshaah]

Hi All

If I understand it correctly, this TSB addresses the head/cylinder leak on the early 964's. Where can I find this TSB? Does the head height indicated in the shop manuals of 84.48+/-0.02mm change after the heads are machined as per the TSB. The manual limits head resurfaces to 2 of 0.1+/-0.02mm each, which would give a minimum limit of 84.28mm {i.e. 84.48 - (2 X 0.1) } - am I interpreting this correctly?

Thanx in advance
Bill
90C2

[cnavarro]

Specifications can be found in Porsche Carrera 964 Technical Data Without Guesswork, Bentley Publishers, 15-4, cylinder head machining.

I don't have the book handy, or I would give you the specs.

[lucittm]

Porshaah,
The number you posted, 84.48 +/- 0.02mm refers to the dimension and tolerance of a NEW head.

According to the Bentley Technical Manual:
"The maximum metal (quoting now) that can be removed from a cylinder head (groups of three) is 0.20 +/-0.02mm".

So your first machining attempt would be 0.10 +/- 0.01mm (0.004"). The second attempt would be the same and then you would be at the limit.

Good Luck,
Mark

[Oracle]

Bill.
Send me your email and I'll send you the TSB