Introducing ... my '84 928 S2 rebuild
12-05-2012, 06:03 AM
#31
Rennlist Member
H Stefan
The application of the X pipe to the 928 is thanks to Louie Ott.
http://www.performance928.com/cgi-bi...ss_parent=1128
His design was taken up with Motorsports in Salt Lake City, and you can buy them from Roger Tyson.
You should be able to pick up 20 HP or more with a properly designed X pipe. But the design has to be right which is why I recommend this version over the others.
The application of the X pipe to the 928 is thanks to Louie Ott.
http://www.performance928.com/cgi-bi...ss_parent=1128
His design was taken up with Motorsports in Salt Lake City, and you can buy them from Roger Tyson.
You should be able to pick up 20 HP or more with a properly designed X pipe. But the design has to be right which is why I recommend this version over the others.
On instinct, I replaced the screwed up first part with 2 separate pipes running all the way to the rear muffler. Meanwhile I've found many references telling me the X-pipe configuration is better, (and it made my to do list) but so far no explanation why.
Choosing to combine the exhausts runs of cylinders has different effects @ different rpm, and the lengths of the pipes and where they come together causes the acoustics to work for or against you.
Clearly, the x-pipe is an improvement over the stock system, but could you tell me more?
Choosing to combine the exhausts runs of cylinders has different effects @ different rpm, and the lengths of the pipes and where they come together causes the acoustics to work for or against you.
Clearly, the x-pipe is an improvement over the stock system, but could you tell me more?
12-05-2012, 06:21 AM
#32
Advanced
Thread Starter
H Stefan
The application of the X pipe to the 928 is thanks to Louie Ott.
http://www.performance928.com/cgi-bi...ss_parent=1128
His design was taken up with Motorsports in Salt Lake City, and you can buy them from Roger Tyson.
You should be able to pick up 20 HP or more with a properly designed X pipe. But the design has to be right which is why I recommend this version over the others.
The application of the X pipe to the 928 is thanks to Louie Ott.
http://www.performance928.com/cgi-bi...ss_parent=1128
His design was taken up with Motorsports in Salt Lake City, and you can buy them from Roger Tyson.
You should be able to pick up 20 HP or more with a properly designed X pipe. But the design has to be right which is why I recommend this version over the others.
12-05-2012, 06:21 AM
#33
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Congratulations - this looks very nice, and has a great option combination. Be careful with the fabric on your seats - I'm not sure the PORSCHE fabric is still available.
More often than you may think... you also see US models registered in Germany. If they lived in CA, they saw little rain, no snow/ice/salt, etc - that's quite desirable when you buy an older car.
More often than you may think... you also see US models registered in Germany. If they lived in CA, they saw little rain, no snow/ice/salt, etc - that's quite desirable when you buy an older car.
12-05-2012, 08:33 AM
#35
Three Wheelin'
12-05-2012, 08:45 AM
#36
Three Wheelin'
BEAUTIFUL !
I like interiors that are uncommon and the wine red interior is extremely good looking imo. I am closing in on 2 cars, same color outside but inside one is black and the other burgundy. My heart is longing firmly for the latter.
But it's much more expensive. Will have to see. It also has option 220 which is a nice bonus too.
I like interiors that are uncommon and the wine red interior is extremely good looking imo. I am closing in on 2 cars, same color outside but inside one is black and the other burgundy. My heart is longing firmly for the latter.
But it's much more expensive. Will have to see. It also has option 220 which is a nice bonus too.
12-05-2012, 02:03 PM
#40
Advanced
Thread Starter
Problem 2
As I had repaired my exhaust system, I took the car out on country roads and revved it. The earlier loss of power at 4000 was replaced by a clear increase as the engine reached the higher rpm's. I could not have been happier.
Time to do a poor man's power test. Cross the border in to Germany and see how fast she goes.
In the mean time I did repair my speedometer because not fixing it proved far more expensive than fixing it. I already collected three speeding tickets
We have an unlimited autobahn, not that far from here and that is where I floored it.
The car jumped up and quickly passed 200 km/h, it moved further at a steady rate until 230, but again, that's when it started to feel inadequate.
I decelerated and was about to give it another go when I noted a tapping noise. I quickly moved to the nearest stop point and got out. It was a clear noise coming from the engine block, one that I had heard many times before, but never on one of my own engines. A connecting rod bearing.
I looked for the noise and located it on the left bank. As I disconnected the second injector, the noise was gone. Clear case.
I limped back home on 7 cylinders, cursing and swearing. In the weekend that followed, I removed the oil pan to assess the damage. That turned out to be a fraction more work than I had anticipated, but once removed I got a look at the crankshaft.
I neglected taking pictures of the details but trust me when I say that it was as bad as it could be.
The second crank (Cyl 4)had welled the bearing to a quarter of it's normal thickness.
The crankshaft itself got damaged in the process, so no luck there. I'm looking at a serious problem.
I spent two weeks thinking about my options, and they were not great.
Fact was that the crankshaft could not be repaired very few companies do this
Even if they would, the undersize bearings are very hard to get
The connecting rod itself is probably oval shaped so it would be a complete teardown.
During the test run I noted blue smoke which indicates other problems.
As it was spring, and all I wanted to do was drive in the summer, I took a radical decision. Perform a temporary fix to keep the engine going for the summer and look for a complete replacement.
I replaced all connecting rod bearings and polished the crank until all scractches were smoothed out using 2000 sandpaper. After assembly it seemed my temp fix had worked. The knock was gone and I finished the whole summer running that engine, going easy on the throttle of course.
In fall I found a replacement, but I was not about to simply throw that one in.
Time to do a poor man's power test. Cross the border in to Germany and see how fast she goes.
In the mean time I did repair my speedometer because not fixing it proved far more expensive than fixing it. I already collected three speeding tickets
We have an unlimited autobahn, not that far from here and that is where I floored it.
The car jumped up and quickly passed 200 km/h, it moved further at a steady rate until 230, but again, that's when it started to feel inadequate.
I decelerated and was about to give it another go when I noted a tapping noise. I quickly moved to the nearest stop point and got out. It was a clear noise coming from the engine block, one that I had heard many times before, but never on one of my own engines. A connecting rod bearing.
I looked for the noise and located it on the left bank. As I disconnected the second injector, the noise was gone. Clear case.
I limped back home on 7 cylinders, cursing and swearing. In the weekend that followed, I removed the oil pan to assess the damage. That turned out to be a fraction more work than I had anticipated, but once removed I got a look at the crankshaft.
I neglected taking pictures of the details but trust me when I say that it was as bad as it could be.
The second crank (Cyl 4)had welled the bearing to a quarter of it's normal thickness.
The crankshaft itself got damaged in the process, so no luck there. I'm looking at a serious problem.
I spent two weeks thinking about my options, and they were not great.
Fact was that the crankshaft could not be repaired very few companies do this
Even if they would, the undersize bearings are very hard to get
The connecting rod itself is probably oval shaped so it would be a complete teardown.
During the test run I noted blue smoke which indicates other problems.
As it was spring, and all I wanted to do was drive in the summer, I took a radical decision. Perform a temporary fix to keep the engine going for the summer and look for a complete replacement.
I replaced all connecting rod bearings and polished the crank until all scractches were smoothed out using 2000 sandpaper. After assembly it seemed my temp fix had worked. The knock was gone and I finished the whole summer running that engine, going easy on the throttle of course.
In fall I found a replacement, but I was not about to simply throw that one in.
12-05-2012, 03:31 PM
#42
Rennlist Member
Stefan, the story certainly gets more interesting! But I am sure sorry to read about the rod bearing failure!
You said it was the second injector on the left, but that would be cyl #6, not 4, correct? Those are the troublesome bearings...
Thank you for posting, and I am very interested to follow the continuing story!
You said it was the second injector on the left, but that would be cyl #6, not 4, correct? Those are the troublesome bearings...
Thank you for posting, and I am very interested to follow the continuing story!
12-05-2012, 03:46 PM
#43
Advanced
Thread Starter
Stefan, the story certainly gets more interesting! But I am sure sorry to read about the rod bearing failure!
You said it was the second injector on the left, but that would be cyl #6, not 4, correct? Those are the troublesome bearings...
Thank you for posting, and I am very interested to follow the continuing story!
You said it was the second injector on the left, but that would be cyl #6, not 4, correct? Those are the troublesome bearings...
Thank you for posting, and I am very interested to follow the continuing story!
12-05-2012, 04:08 PM
#44
Advanced
Thread Starter
M28
So in the Fall of 2011, I had found a replacement block. An M28.22, I really wanted a 21(manual) but that seemed virtually impossible and apparently the stamped nr is the only difference.
According to the seller it was good to run and I could do the swap over the weekend
but I did not think so
I was afraid the same thing would happen all over again and then the car would kill my bank account. I started disassembly with the intent only to change the bearings, but quickly changed my mind. The gasket sets are very expensive over here, but there is no point in doing half a job.
Take it apart, completely.
Pretty soon, my garage was filled with components
According to the seller it was good to run and I could do the swap over the weekend
but I did not think soI was afraid the same thing would happen all over again and then the car would kill my bank account. I started disassembly with the intent only to change the bearings, but quickly changed my mind. The gasket sets are very expensive over here, but there is no point in doing half a job.
Take it apart, completely.
Pretty soon, my garage was filled with components
12-05-2012, 04:32 PM
#45
Advanced
Thread Starter
Preliminary checks of the cylinders were looking good
But the engine block was filthy, I couldn't leave it like that, so I went to work with immense amounts of brake cleaner. That stuff gave me one of the worst hangovers ever.
A proper mask proved the solution.
The Alusil block turns out to have a nice natural shine to it and a simple brush will do miracles
All of this did take several weeks, every chance I got I was in the basement for an hour or two.
In the meantime, I started ordering the necessary parts
Main bearings
Rod bearings
Piston rings
Valve springs (one main inlet spring turned out to be broken, glad I caught that)
Water pump
Timing belt & tensioners
and the pricy gasket set
The heads were machined, valves grinded and bedded in
Tested and approved.
Meanwhile I decided I wanted this engine to look good on top of running well.
Some trials with the cam covers
It was quite clear what to do. Ruby Red!!!! and polished aluminium plugs
But the engine block was filthy, I couldn't leave it like that, so I went to work with immense amounts of brake cleaner. That stuff gave me one of the worst hangovers ever.
A proper mask proved the solution.The Alusil block turns out to have a nice natural shine to it and a simple brush will do miracles
All of this did take several weeks, every chance I got I was in the basement for an hour or two.
In the meantime, I started ordering the necessary parts
Main bearings
Rod bearings
Piston rings
Valve springs (one main inlet spring turned out to be broken, glad I caught that)
Water pump
Timing belt & tensioners
and the pricy gasket set
The heads were machined, valves grinded and bedded in
Tested and approved.
Meanwhile I decided I wanted this engine to look good on top of running well.
Some trials with the cam covers
It was quite clear what to do. Ruby Red!!!! and polished aluminium plugs