dcdude

An owner of a well-known independant shop told me that "Porsche continuously upgrades its valve guide material. Anyone who orders valve guides will automatically receive the latest and greatest "stock" valve guides from PCNA, which should now excusively be phosphor-bronze. Even if you get them in the aftermarket, it's still a Porsche part."

To me, this means that there are no aftermarket valve guides !? Can that possibly be true?

The ower of a machine shop that does a bunch of P-car heads says, "I don't use the Porsche part (I presume because they're still soft brass). You have to use aftermarket. There's one supplier in California called "SI"(?) that makes good ones. There's another in the Vegas area where I get the manganese(SP?)-bronze guides that I use."

Who's right here? Neither? Both?

Father of 3

Have you found a car yet? You remind me of me when I was looking. I used to ask questions like this during my search.

I'll defer to the experts but my guess is to say that it is doubtful that Porsche would upgrade past SKUs like this. I would assume that through R&D and investment they upgrade their materials throughout the car, including the valve guides for newer models. Why spend money to fix post-warranty parts that are not a safety issue?

If you want the skinny on valve guides, I would call Steve Weiner who is the man on this issue. He is very helpful and good to this board.

Good luck with the search.

Leander

I too was told earlier this week by an indie in the Bay Area that Porsche has upgraded its valve guides, and there should be no problem with them if you've had to replace them post-2001. This indie does prefer to use the aftermarkets though.

Flying Finn

I'm not sure about the 996 & 997 guides but for others, Porsche has used pretty much the same (bad) stuff since who knows when. Maybe they've upgraded the material but it ain't up to a par with the good aftermarket stuff.

Kika

I believe Steve Weiner (Rennsport) advocates the use of Magnesium Bronze Guides for the 993

FLYT993

I was about to post a similar question...because in going through my P-Car magazines, I noticed that Colin of 9M upgrades to "sintered steel" valve guides, so now I'm curious as to the difference between them.

Steve Weiner-Rennsport Systems

LOL,..We've been making our own Phosphorus-Bronze guides for 25+ years and that material is FAR more durable than the Porsche factory ones.

We did a GT-3 Cup engine about a year ago that still had the old, soft crappy guides in it.

black ice

I don't know what theirs are made of, but look nice
http://www.heritagemotorcar.com/

autobonrun

Jones Autowerks in San Antonio told me they use a much better aftermarket set when they have to rebuild; and have been doing so for years. I don't remember the details but I'll try to find out from them.

FLYT993

Guides are made from "advanced alloy"...which only adds to my confusion...Steve makes "Phosphorus bronze"...9M makes the "sintered steel"...and Porsche, ostensibly, used something inferior to both. For the experts out there....what is the conclusion?