The Twin Screw Thread
#1471
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Originally Posted by SharkSkin
Dave, are you considering a CIS variant?
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David Roberts
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#1474
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Originally Posted by Imo000
Are you over tightening it?
#1475
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Well I had an interesting weekend - don't worry nothing broke. ![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
I discovered 2 things.
#1 My digital boost gage is inaccurate. I did a couple of data logging sessions and while my boost gage will get up to 6.0psi and then start to fall off down to 0, the Innovate AUXBox MAP sensor shows that I'm hitting about 6.5 psi and holding it all the way to redline. What's interesting is that I "T" off the same line in the passenger footwell. I would think if there was a leak in the line, both would show the loss. I have an analogue gage that I think I'll try to confirm which is more accurate.
#2 I was using Theo's diagnostic computer and did a knock count on a 2nd gear pull to redline and registered 50 knocks the first time and 75 the 2nd. Hmmm.... Something's amiss.
I think I need to get the SharkTuner up here and figure out which cylinder is knocking. But before I do that, I'll try a fresh tank of gas as my last one was only 92 octane. This time I'll make sure it's 93.
Of course all my data is on the other PC. I'll post graphs and other pretty pictures later tonight when I get home.
![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
I discovered 2 things.
#1 My digital boost gage is inaccurate. I did a couple of data logging sessions and while my boost gage will get up to 6.0psi and then start to fall off down to 0, the Innovate AUXBox MAP sensor shows that I'm hitting about 6.5 psi and holding it all the way to redline. What's interesting is that I "T" off the same line in the passenger footwell. I would think if there was a leak in the line, both would show the loss. I have an analogue gage that I think I'll try to confirm which is more accurate.
#2 I was using Theo's diagnostic computer and did a knock count on a 2nd gear pull to redline and registered 50 knocks the first time and 75 the 2nd. Hmmm.... Something's amiss.
![Confused](https://rennlist.com/forums/images/smilies/confused.gif)
Of course all my data is on the other PC. I'll post graphs and other pretty pictures later tonight when I get home.
#1476
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Hello Andrew
The diagnostic tester measure the total number of knocks (all cylinders) in 10,000 cylinder firings and the failure point set by Porsche is that there should be less than 25 knocks in that time. The Spanner shows the number of knocks after 10,00 firings after the "go" button is pressed, and then whether that is a pass or fail.
Your data logs should enable to you estimate the number of firings you collected in that 2nd gear run. The engine has four firings per rev of course.
The SharkTuner will show you the total number of knocks, but more usefully it will also allow you to monitor and datalog the knocks on each individual cylinder.
See the section in the SharkTuner User Manual for more info on EZK mapping.
The diagnostic tester measure the total number of knocks (all cylinders) in 10,000 cylinder firings and the failure point set by Porsche is that there should be less than 25 knocks in that time. The Spanner shows the number of knocks after 10,00 firings after the "go" button is pressed, and then whether that is a pass or fail.
Your data logs should enable to you estimate the number of firings you collected in that 2nd gear run. The engine has four firings per rev of course.
The SharkTuner will show you the total number of knocks, but more usefully it will also allow you to monitor and datalog the knocks on each individual cylinder.
See the section in the SharkTuner User Manual for more info on EZK mapping.
#1477
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Thanks John-
I've seen that part of the ST in action and it is a great tool!
Theo's unit does give you total firings and the # of knocks during that period. But it only gives the total knocks and does not indicate which cylinder. But at least it gives an indication.
It's clear I need use of the ST.
I've seen that part of the ST in action and it is a great tool!
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It's clear I need use of the ST.
#1479
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Originally Posted by John Speake
Hi Andrew,
So how many firings during the run when you collected 50/75 total knocks ?
So how many firings during the run when you collected 50/75 total knocks ?
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Certainly looks like rather too many knocks...... it will take up to 15 seconds for the igntion to gradually advance back to the mapped values on the affected cylinders.
Have your injectors been ultrasonically cleaned and flow tested recently ?
Have your injectors been ultrasonically cleaned and flow tested recently ?
#1485
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Originally Posted by John Speake
Certainly looks like rather too many knocks...... it will take up to 15 seconds for the igntion to gradually advance back to the mapped values on the affected cylinders.
Have your injectors been ultrasonically cleaned and flow tested recently ?
Have your injectors been ultrasonically cleaned and flow tested recently ?
Last edited by AO; 06-19-2007 at 10:15 AM.