How soon after getting your car before engine rebuild

[b930]

Bought mine as a mint original with 72k miles. I went in for a few oil leaks and its ended per my sig.

[kinda]

I miss read this as well and thought the price offered was $14k. I'm just starting to look into purchasing one and live in Atlanta. My wife thought I was having a seizure or something the way I was scrambling around to contact Rob.

Someone else mentioned a tech named Franz, where is he located? Contact info? I would love to know that a good reliable source for service is available local before buying.

Thanks for the help!

[Ram930]

Thanks for all of the responses guys. Sorry about the wording that makes it sound like the list price was $14k. (I would buy it off of myself at that price. ) I would be in for not much more than the engine rebuild cost me. I am selling because I am looking to go in a different direction as far as big boy toys go, so I am not desperate to get just any price to get rid of it. I posted this because I needed to see if I was off base by not discounting the price because of the engine rebuild. It seems as though most of you are with me in thinking that these cars are not devalued if the rebuild is done right by someone that knows what they are doing.

Thanks again Rob

[JFairman]

Rebuilding the motor correctly even if it's only a top end rebuild only increases the value of them.

One short little reason: The exhaust valves in the 911 turbo motor are worn out by the time they reach 40,000 miles because of the intense cyclinder head and exhaust port heat in these turbo motors.
That is a fact and just ask Bob at Xtreme Cylinderheads index if you don't want to believe it.

To replace them you should do more than just a remove and replace, you should do a top end rebuild or overhaul.

[gsxrken]

One short little reason: The exhaust valves in the 911 turbo motor are worn out by the time they reach 40,000 miles because of the intense cyclinder head and exhaust port heat in these turbo motors.

That is a fact and just ask Bob at Xtreme Cylinderheads index if you don't want to believe it.

I have bookmarked him from previous research for my own eventual needs.
However, my car has 99k and good compression test results. Uses a little oil but so what. I think saying that the exhaust valves were worn out 20 years and 50k milea ago is probably too strong a statement.
To the OP, I have my car for 11 years and haven't rebuilt it. I'm sure it would benefit from one now, but it would be elective and for peace of mind.

[JFairman]

My email is open almost all day, and I just want to say i'm not lurking all the time... I have email notifications from this site so I'll reply to you.

These cars will continue to run pretty darn good with worn exhaust valve guides. It is surprising maybe but they do, especially on boost when the boost pressure compensates for alot of cylinder, piston ring, valve guide, and seat wear and masks it hiding it.

It's really easy to check for valve guide wear... Next time you have the rocker covers off take a sturdy screwdriver and gently use it as a prybar between a solid area of the cam tower and the valve spring retainer.
After around 40,000 miles of use on the engine and valve guides you will easily be able to nudge or wiggle the top valve spring retainer back and forth sideways. When they are new and fit correctly you can't move them sideways at all and after a while you can because metal has worn away inside the valve guide.

Now the degree of wear over mileage directly relates to how hard the motor has been driven under boost and how often high rpms have been run and the oil used.

If the car is driven slow around town most of the time with little boost they will last alot longer but thats not the usual case with these cars...
The exhaust valve guides wear out 4 to 6 times faster than the intake valve guides because of the extreme difference in high temperature heat on them.
I've never seen any other car wear out the exhaust valvguides as fast as these things do.

Anyway, take it for what it's worth. Call him and ask him if you want. He's a really cool guy. 40,000 miles were his words in a recent in person conversation I had with him when I was up at his shop having work done on some 1976 930 heads for a 95mm bore 3.0 liter motor I have so they can be installed in a 97mm bore 3.3 liter motor.

In my opinion and limited experience on these cars, if the car is tracked a few times a year at DE events or whatever the exhaust valve guides are worn out after around 25,000 miles. They still work and the motor runs pretty good but there is sideways play in the exhaust valves and if you look up in the exhaust ports with a light when the headers are off you will see alot of crusty burnt oil build up around the valve guides and valve stems in the ports because oil is leaking down there from the excessive clearance between valve stem and valve guide. That is often part of the reason for a puff of smoke on start up after it sits a while.
I've mentioned that to some excellent local Porsche mechanics around here and they agreed. So, it all comes down to how hard the car is driven...

I'm not an expert at all but Bill at xtreme cylinder heads is and many many people consider him the absolute best at porsche cylinder head work and modifications in the USA, period. Truth is no one else even comes close...
He also builds some killer custom 911 heads from the ground up with new castings he designed. You can see them and his amazing CNC porting on his website I posted a link to in my earlier post. Or just google xtreme cylinder heads.