K-line valve guides

[Zendalar]

I just took my cylinder heads to be machined and the shopkeeper said that they will not replace the old with genuine Porsche parts but they will put these new kinda guides in with the old ones. They are called K-lines.

The old guides are to be drilled 0,75 mm bigger and then the k-line guide is put in with the old one. They are said to last lot longer than the original.

Whats your opinion?

[Thomas Owen]

Zen,
My take on valve guide wear has always laid the blame on the valve stem seals, not the guides themselves. The seals did not allow enough oil to the stem, and wear resulted. I suppose you could replace the original guides with anything (I would only use the original Porsche part) but without the proper seals (the white ones) you could get early guide wear again. I just replaced all guides and valves in my '88 at 110,000 miles with the original guides and white seals and I do not feel I have anything to worry about for years.
Regards,

[Early_S_Man]

Zen,

The factory choice for valve guide material for '65 thru '76 was a high-copper alloy bronze that had very high heat conductivity, but it wore too fast even with an ample supply of oil past the white Teflon Perfect-Circle seals! After three years of extroidinarily high temperatures in the CIS 2.7 engines, and many replacement engines installed free in the hotter regions of the USA, a running change was made to a silicone-bronze alloy valve guide during 1977 production that proved very satisfactory in the SC production engines!

I am not familiar with the guides you mentioned, but if they are similar to the SC production guides, they will be fine!

[RoninLB]

Head work on these engines should only be done by a porsche experienced guy. When I found out how critical 911 head work is I sent them to Competition Engineering in Calif. If CE is good enough for Bruce A and other big people in PANO they are good enough for me. If your machinest is not an expert get them back and send them to the right people. There are a few well known 911 mach. in US that do noticably great work.

[Zendalar]

Well, here in Finland there are very few Porsche experts, actually we have only only one shop that offers spare parts to Porsches and know something about them at the same time. There are others but they just order parts and know jack nor ***** about them.

This machinist has rebuilt couple 911 engines, so I guess I am covered.

[RoninLB]

ZEN---send your eng parts to U.S. May be a good deal on $exchange rate. Do you have some kind of delivery system in your world or do you still use Pigeon Express. Our women can take lessons from your women, I'm told. Be careful about a vacation here, you may not want to return. Women in U.S. get wet when they talk to Euro men. Therefore you can eat to your hearts content.

[Zendalar]

Heh Well, shipping across the world (overseas) is very expensive, and then there are tolls and such.

When I took the parts to this mechanic I told him that : "Yes, yes, I know they are Porsche parts, but don't you tell me that to have that kinda car you need to have cash to fix it.

He told me that, car is a car, some might put in a Porsche bonus, but not he.

911 just has to be dealt with more gentle touch.

[Bill Douglas]

Ronin, Zen would be bored ****less with US women. I think you need to meet some women from Finland to see what looks and style are about. Also why send car parts to the states, Finland is a short ferry ride from Germany?

[RoninLB]

Wild Bill--My friend went to Finland to teach SCUBA diving for 2 years. He said he will never get involved with a U.S. woman again.

[Bill Douglas]

Ronin, after I post that i thought I was generalising too much and thinking a little to fondy of my last european holiday - then I thought WTF, Finish women are incredible

[RoninLB]

If it tastes good---- Feed Me