Quote:
Originally Posted by TurboKraft
The bouncing oil gauge is the mystery -- for sure the level gauge, correct? You say that pressure didn't appear to be affected.
Oil still blowing out the exhaust? Is she still running okay?
A cold, dry cylinder leakdown test will tell you a lot about the internal condition of the engine.
These scenarios are another reason we advocate for a -0.5 -- 1.5bar 935-style boost gauge: you get a sense of what "normal" vacuum for your engine is at idle, A/C off.
If you mechanically hurt the engine, either break a ring or blow a seal, you typically lose some vacuum and it registers on the gauge. If you're drawing the same vacuum as always, it's more likely everything is fine mechanically (no blown out o-rings or top rings) and it's something else (turbo seal failure, etc.)
FWIW: stock cams are usually done by 5,500rpm, and most factory sport cams (SC, 964) peak by 5,800-6,200rpm. Once the cams peak, there's really no sense in revving it higher.
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Thanks for the great insight Chris (I need to reach out to you and get more information about getting her out to AZ to get her sorted out). In regards to the car, it seemed to drive okay, I really babied on the way home. Just lots of white smoke from the exhaust. The car has 964 cams, not sure the type (the seller was a pretty wealthy open check book guy when he had the car built). Looks like I was wrong, she is on stock pistons. It does have a 935 boost gauge, but unfortuanetly doesn't work
This was the description I got when communicating during purchase:
"The sequence of events on this 34,000 mile car are as follows:
A decision was made to remove the stock low horsepower engine in 2005-2006 at about 26,000 miles. He had owned the car for 15 years by this time. He wanted the car to keep up with, or beat new Turbos. He enlisted the professional help of Joe Rodriguez (JROD) owner of FAST FORWARD, a premier Porsche speedshop based in Ft. Lauderdale. Joe consulted Joe Eassa, a local fabrication expert as he had a working relationship with the legendary Dave Jarvis Racing Co. Jarvis built the engine and Joe Eassa fabricated the headers, Turbo (precision) and intercooler (Griffin core). The engine was installed, tuned and tested by Fast Forward. As the warranty had expired after the first year, it's now had trouble-free operation for the last 12 years. Being that Jarvis had retired and Fast Forward was sold 10 years ago, the record keeping on various projects has long been discarded. Knowing this, Jim had asked Joe Rodriguez to inspect and scope the engine recently. What Joe found was an engine that showed virtually no signs of wear (7,500 miles) and noticed some minor seepage that was quickly rectified. What we do know is that the engine is capable of 620 hp. What we also know is that its currently tuned at about 400 rwh. However this engine is made for boost. It starts and runs strong and smooth, very streetable in its current tune. Any minor issue that would arise over the years identified and corrected by local Porsche techs, including JROD. As a multiple Porsche owner myself I can tell you that the car has been well sorted and has been a joy to drive.
If you need any further clarification on engine components or
tune, I can put you in touch with JROD. As he is a full-time Senior Captain who flys 747's for a national airline, he is frequently out of the country but can be reached by email, text or a call from time to time. We know from his memory and recent scoping that it has 964 cams, stock Porsche pistons and rods, ARP rod bolts, ARP head studs, brand new Turbo seals, Electromotive dual plug head setup and EFI. 3.3 liter. Injectors, other ignition and fuel management questions can be addressed by Joe.