geoorlando

What are good results?

chsu74

150s if I remember correctly. What matters is that all six cylinders are consistent in numbers.

geoorlando

Thanks so much for the response. This has been many posts on this but it is hard to figure out which are correct- many exceeding my technical knowledge. What does seem to be the case (and makes sense) if that the Turbos have lower compression with numbers like 150 being associated with naturally aspirated cars:

https://rennlist.com/forums/993-foru...ng-theory.html

This post states a theoretical compression ratio of 120 which is about where my car is coming in. However, there are other factors that seem to establish tolerances around this.

Best,

G.:

chsu74

You are right. Just pulled up my 3TT PPI and compression shows 122-125 PSI.

geoorlando

Thanks for responding! I greatly appreciate it!

Best,

G.

Mike J

Yah, that is about right, but there is also variance with the equipment/calibration, and technique. Some people crank 5 revs, some 7, some until the needle is peaked. I like the last because it's what the car can maximum do - but as mentioned before, its really the relative values across all pistons that is important.

solomonschris

When I bought my 993tt the ppi compression test was great. I was going to proceed with the purchase until members of this forum at the time, vociferously encouraged me to pay the extra cost for a leakdown test. I thought that was silly since the car had about 22K miles as I recall. I did take their advice though and when the leakdown test was performed 5 cylinders were within a point or two from 100% with one in the teens. Valve guides were the culprit. The valve stems didn’t “wiggle” on any of the seats so I think a leakdown is a must do.

The seller, a gentleman of the highest order, paid for the valve job. The ppi and subsequent repair was performed by Schneider Autohaus in Santa Barbara. They replaced $6,500 of other parts on my account as a result of the ”while you’re in there disease” caused by the heretofore mentioned forum members. If I need a 911 engine rebuild I would ship it to Schneider’s Autohaus and I live in Maryland!

I am now 74 and no doubt vividly remember things that did not actually occur and have forgotten many things that did.
Over the years I have accumulated a few regrets including selling every Porsche I’ve ever owned. That list includes a rusted out 356 coupe in college, 2 911 coupes, an pto 89’ 930 cab, 3 993 coupes, a 993tt, an ‘09 997S cab (first new Porsche), and present 991S cab. Just guess which one I miss the most and it has nothing to do with the “ investment instrument” it has turned out to be. My unsolicited advice...buy 911 Porsche’s...don’t sell them. Chris

geoorlando

Hi Chris,

Thanks for such a thoughtful and eloquent response. Ironically, I have been a bit conflicted about giving up on of my other vehicles to get into a 993TT. But to your point, this has happened with every Porsche that I have owned. Conversely, I have come to appreciate each model for what it is.

Thanks, again.

Best regards,

G.

rlme36

The only thing I would add to your thought process is, they aren't making any more of the 993TT's, the new vers are great and very capable cars, but there is quantity of them if you should ever feel the need to rekindle that flame. my 2 cents