944S3 bites the dust...
08-07-2009, 04:01 AM
#17
Race Car
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Join Date: Jun 2003
Location: Albany, CA: celebrating 100 years of independence from Berkeley, CA
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I'm in Berkeley -- not in SoCal anymore. I used to work in SoCal, but the 400mile commute from NorCal was killing me!
V2 was up here visiting his brother and had spare time to kill - so we traded labor for cash.
Here's what it used to look like. No front damper pulley -- but I never vibration problems.
The air filter setup was not the ideal -- just a K&N cone filter. I was in the process of using a S2 air filter stuffed underneath a 924turbo nose panel (won't fit under a stock nose panel). Never got around to it...
V2 was up here visiting his brother and had spare time to kill - so we traded labor for cash.
The air filter setup was not the ideal -- just a K&N cone filter. I was in the process of using a S2 air filter stuffed underneath a 924turbo nose panel (won't fit under a stock nose panel). Never got around to it...
08-07-2009, 09:45 AM
#18
Nordschleife Master
If you remove the lights and all associated hardware, the filter can sit under the headlight flap. There is a whole in the side that you can feed fresh "cold" air to the filter.
Below is a mockup from when I built my car using the filter from my F150. I currently have a much larger cone filter stuffed in there, just barely fits
Below is a mockup from when I built my car using the filter from my F150. I currently have a much larger cone filter stuffed in there, just barely fits
08-07-2009, 11:17 AM
#21
Nordschleife Master
I'm in Berkeley -- not in SoCal anymore. I used to work in SoCal, but the 400mile commute from NorCal was killing me!
V2 was up here visiting his brother and had spare time to kill - so we traded labor for cash.
Here's what it used to look like. No front damper pulley -- but I never vibration problems.
V2 was up here visiting his brother and had spare time to kill - so we traded labor for cash.
Here's what it used to look like. No front damper pulley -- but I never vibration problems.
Based on the fact you have been tracking the car, and running higher rev's...the crank's harmonic distortion (if not properly balanced) may have caused the pistons to shift inside the cylinders. Looking at the photos with the chips on the pistons, really supports this theory.
I think this may be one of the best reasons to see why that damper is needed with this engine. I think the guys on the 968 forum should see this as well. There may very well be a good lesson here. Harmonic vibration is something worth looking at if you are running a 3L motor and lightweight flywheel.
I am sorry for your loss. There's a lot of work that goes into making one of these. I feel for ya. But, on a brighter note - there may be a good lesson in here.
Chad
08-07-2009, 12:40 PM
#22
Race Car
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Agreed. The harmonics is one potential cause. I had neither the S2 pulley/harmonic dampener nor the dual-mass flywheel (was running a S2 flywheel). Lots of 968 guys also run lightened flywheel...
And after much thought, there are two other potential culprits.
One possibility is an aftermarket chip: might have messed with the fuel mixture causing denotation.
Another possibility is oil level. The car had a faulty oil level sender, so if anything was wrong, there wouldn't have been any warning.
And after much thought, there are two other potential culprits.
One possibility is an aftermarket chip: might have messed with the fuel mixture causing denotation.
Another possibility is oil level. The car had a faulty oil level sender, so if anything was wrong, there wouldn't have been any warning.
08-07-2009, 01:08 PM
#24
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I was using the "Racer X" chip from speed-6.com (I don't think they make these anymore) -- which bumped the rev limiter all the way up to 7800rpm, if I recall.... But I never bounce off the rev limiter -- I tend to to be an early shifter, at not much past 6000. But then, it's not like I'm staring at the tach....
08-07-2009, 01:20 PM
#25
Nordschleife Master
I was using the "Racer X" chip from speed-6.com (I don't think they make these anymore) -- which bumped the rev limiter all the way up to 7800rpm, if I recall.... But I never bounce off the rev limiter -- I tend to to be an early shifter, at not much past 6000. But then, it's not like I'm staring at the tach....
C.
08-07-2009, 01:32 PM
#26
Rainman
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the valves all looked good, no damage to any of them, the spark plugs were all intact.
hard to see in the pictures but on the #2 piston there were places where small pieces of piston were missing from the edge of the crown. like, a full milimeter on the bottom of the piston and about the same on the top. you could see the top piston ring, and how a piece of it appears to be missing...
the #4 has a chip in the top of the piston and also has a small chunk missing. based on the chip i think something must have gotten into the cylinder and bounced around, maybe even something that was already in the intake tract....
the head was in fabulous condition actually. this engine would be useable if someone wanted to take it up to 106mm or resleeve it to 104..i highly doubt that taking it to 104.5 would be enough, there is a HUGE gash in the #4 wall.
hard to see in the pictures but on the #2 piston there were places where small pieces of piston were missing from the edge of the crown. like, a full milimeter on the bottom of the piston and about the same on the top. you could see the top piston ring, and how a piece of it appears to be missing...
the #4 has a chip in the top of the piston and also has a small chunk missing. based on the chip i think something must have gotten into the cylinder and bounced around, maybe even something that was already in the intake tract....
the head was in fabulous condition actually. this engine would be useable if someone wanted to take it up to 106mm or resleeve it to 104..i highly doubt that taking it to 104.5 would be enough, there is a HUGE gash in the #4 wall.
08-07-2009, 03:27 PM
#27
Nordschleife Master
the valves all looked good, no damage to any of them, the spark plugs were all intact.
hard to see in the pictures but on the #2 piston there were places where small pieces of piston were missing from the edge of the crown. like, a full milimeter on the bottom of the piston and about the same on the top. you could see the top piston ring, and how a piece of it appears to be missing...
the #4 has a chip in the top of the piston and also has a small chunk missing. based on the chip i think something must have gotten into the cylinder and bounced around, maybe even something that was already in the intake tract....
the head was in fabulous condition actually. this engine would be useable if someone wanted to take it up to 106mm or resleeve it to 104..i highly doubt that taking it to 104.5 would be enough, there is a HUGE gash in the #4 wall.
hard to see in the pictures but on the #2 piston there were places where small pieces of piston were missing from the edge of the crown. like, a full milimeter on the bottom of the piston and about the same on the top. you could see the top piston ring, and how a piece of it appears to be missing...
the #4 has a chip in the top of the piston and also has a small chunk missing. based on the chip i think something must have gotten into the cylinder and bounced around, maybe even something that was already in the intake tract....
the head was in fabulous condition actually. this engine would be useable if someone wanted to take it up to 106mm or resleeve it to 104..i highly doubt that taking it to 104.5 would be enough, there is a HUGE gash in the #4 wall.
C.
08-07-2009, 08:10 PM
#28
Rainman
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i went back to san diego yesterday, now it is up to joseph to do the "autopsy". there appeared to be a sizeable piece of ring missing (like an inch or more), judging by the visible ring that suddenly ended and was just black space for the rest of the hole that could be seen though
08-07-2009, 09:11 PM
#29
Detonation can do bad things to the top compression ring. I had a chip in my (NA) for a while and blew a head gasket at the track. When the head came off, number 4 cylinder was badly scraped and disassembly showed the top ring on all 4 pistons was cracked into several pieces. I had hear some pre-ignition noises prior to the HG event but failed to appreciate how bad it was. I was able to get it re-bored but had to go with full 1mm oversize pistons...
08-09-2009, 01:01 PM
#30
Rennlist Member
