Louis Ott's full valve cover video now on youtube
06-18-2010, 07:40 AM
#106
Just thought I would add this link to the thread, given I have also added some dry sump info earlier, it is a worthwhile read if you are thinking of dry sump with some people who have been there done that.
I haven't received my Formula 1 oil tank yet as it was delayed because of buying a caliper but it will be interesting to see how they plumb it up. What is discussed in the link is pulling a vacuum on the oil tank.
http://speedtalk.com/forum/viewtopic.php?f=1&t=14198
Greg
I haven't received my Formula 1 oil tank yet as it was delayed because of buying a caliper but it will be interesting to see how they plumb it up. What is discussed in the link is pulling a vacuum on the oil tank.
http://speedtalk.com/forum/viewtopic.php?f=1&t=14198
Greg
06-18-2010, 09:13 AM
#107
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Give it a lot of thought if you choose to set it up that way. It might be an issue if the 928 pump bypasses significantly more of its output volume back into the inlet than the circuit requires at some pressure. That would create a transitory degrading loop that would open the possibility that the pump drawing a vacuum on the tank could create a break in the feed flow. It might only occur at certain rpms and/or temps. Fun.
If you remove the pressure return bypass into the inlet of the 928 pump (the aforementioned trickiness) then you will need to be dead certain that the average collective scavenging capacity of your pumps is greater than the 928 pump. And I would suggest running the numbers if your engine is under a prevailing acceleration such that only one (?) scavange stage is collecting and refilling the tank. How many seconds of safety margin will you have, etc.
If you remove the pressure return bypass into the inlet of the 928 pump (the aforementioned trickiness) then you will need to be dead certain that the average collective scavenging capacity of your pumps is greater than the 928 pump. And I would suggest running the numbers if your engine is under a prevailing acceleration such that only one (?) scavange stage is collecting and refilling the tank. How many seconds of safety margin will you have, etc.
06-18-2010, 09:40 AM
#109
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06-18-2010, 10:00 AM
#110
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I will be fascinated to hear you expound on why the final car campaigned through back door support was able to survive with only a GTS tray which does not prevent oil from exiting the sump under steady acceleration. This combined with the knowledge from direct measurement that a lateral 30 degree angle of repose -- much less than 1G lateral acceleration -- will uncover the edge of the pickup and that the engine was often running at the 7000 rpm level. I have already given the amount of oil that is displaced from the sump and that will flood the side of the engine. Remember -- you are not allowed to use the concept of air entrainment. This is imaginary. Right?
06-18-2010, 10:07 AM
#111
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The engines (original and replacement) were stated to be selected high output examples held by the factory. That would be a stock engine. We would not want to be accused of mind reading or second guessing what was stated. Right?
I am still patiently waiting for your detailed explanation.
I am still patiently waiting for your detailed explanation.
06-18-2010, 01:59 PM
#112
Rennlist Member
Has anyone really tested the screens and scrapers to see if they even allow the flowback to the sump? my guess is that is the problem in the recent flurry of oil starved rod bearings.
06-18-2010, 02:48 PM
#113
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Originally Posted by swaybar
Kevin's I-J crankscraper system addresses this issue with machined cups which fit over those holes which exit from the block at crank-level on the driver-side, and funnels the oil from the head down into the sump away from the rotating crank. It is so cool!
As I reported before, I have the complete I-J crankscraper system in my new wet-liner engine in my GT race car. As a testament on how well it works, after coming in from a 20-minute session at Road America, the Accusump was barely warm, 80-ish degrees on a 65-degree day; we were flabbergasted it was so cool!
That crankscraper works so well controlling the oil that the Accusump hardly ever cycles which is borne-out by the Accusump's low temperature after a hard session. Before the crankscraper, the Accusump would be 210-degrees after a session.
And let me tell you, that crankscraper is a piece of 'Auto Art'; it is simply beautiful to behold, and very complex. Todd who built my engine was literally beside himself admiring what a nice piece it is.
So the bottom-line is, if you are tracking your car and do not have a dry-sump, then it would be prudent to drill the crank (..my new engine's crank is drilled), and install Kevin's I-J crankscraper system since it obviously works.
As I reported before, I have the complete I-J crankscraper system in my new wet-liner engine in my GT race car. As a testament on how well it works, after coming in from a 20-minute session at Road America, the Accusump was barely warm, 80-ish degrees on a 65-degree day; we were flabbergasted it was so cool!
That crankscraper works so well controlling the oil that the Accusump hardly ever cycles which is borne-out by the Accusump's low temperature after a hard session. Before the crankscraper, the Accusump would be 210-degrees after a session.
And let me tell you, that crankscraper is a piece of 'Auto Art'; it is simply beautiful to behold, and very complex. Todd who built my engine was literally beside himself admiring what a nice piece it is.
So the bottom-line is, if you are tracking your car and do not have a dry-sump, then it would be prudent to drill the crank (..my new engine's crank is drilled), and install Kevin's I-J crankscraper system since it obviously works.
Directing the draining oil away from the counterweights is mentioned in the FEV SAE paper. It can also be observed in the BMW and Toyota redesigns of their 4 and six cylinder blocks from 20 years ago.
06-18-2010, 05:46 PM
#114
Nordschleife Master
Thread Starter
I will be fascinated to hear you expound on why the final car campaigned through back door support was able to survive with only a GTS tray which does not prevent oil from exiting the sump under steady acceleration. This combined with the knowledge from direct measurement that a lateral 30 degree angle of repose -- much less than 1G lateral acceleration -- will uncover the edge of the pickup and that the engine was often running at the 7000 rpm level. I have already given the amount of oil that is displaced from the sump and that will flood the side of the engine.
Claims 1 and 2 imply that it was a GTS engine. If you look at the Service Info Tech 92, you'll see the GTS power and torque curves on page 1-2 and the GTS gear ratios on page 3-7. Given the peak power being produced at 5700 rpm and the peak torque at 4250rpm, I seriously doubt they raced a stock GTS engine at 7000 rpm. Especially since the stock engine is electronically rev limited to 6600 rpm -- how do you race that stock engine at 7000 rpm, even if you specifically want to do so and don't mind the slower lap times?!
One or more of your above claims are not true. In two posts, you have demonstrated your tendency to just make stuff up and post that made up stuff with authority.
I could get into the pickup uncovering angles/g-forces per direction, but I am not going to bother.
06-18-2010, 06:41 PM
#115
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thats a little different that only using gravity to force the oil through a fine screen system covering the crank.
There has been a few blown motors recently, all with elaborate screen systems. could be the culprit.
ever try to see how much oil can flow through the screen systems? curious. et it cant flow 15 gallons per min like the pump and the sump can.
mk
There has been a few blown motors recently, all with elaborate screen systems. could be the culprit.
ever try to see how much oil can flow through the screen systems? curious. et it cant flow 15 gallons per min like the pump and the sump can.
mk
Mark -- maybe you mean the stock screening that Porsche used over the early sumps? They did try at least two different mesh sizes.
Directing the draining oil away from the counterweights is mentioned in the FEV SAE paper. It can also be observed in the BMW and Toyota redesigns of their 4 and six cylinder blocks from 20 years ago.
Directing the draining oil away from the counterweights is mentioned in the FEV SAE paper. It can also be observed in the BMW and Toyota redesigns of their 4 and six cylinder blocks from 20 years ago.
06-18-2010, 06:45 PM
#116
Rennlist Member
Depending on the HP curves, it might make a lot of sense to run to 7000rpm, even if the peak HP is at 5700rpm. the gains might be slight, but there would certainly be advantages, unless the fell off so dramatically that there was less hp at 7000hp than there would be at 5000rpm, which would be the shift point. Which certainly could be possible. doesnt the GTS run to like GT engine speeds too, which is set at 6800rpm as the limit, or does it limit the engine at 6600rpm like the stock S4?
sorry to butt in.
mk
sorry to butt in.
mk
So what you are telling me is that, (1) a stock engine was raced for a season without failure, (2) this completely stock engine had a GTS baffle, (3) the engine was raced at 7000 rpm
Claims 1 and 2 imply that it was a GTS engine. If you look at the Service Info Tech 92, you'll see the GTS power and torque curves on page 1-2 and the GTS gear ratios on page 3-7. Given the peak power being produced at 5700 rpm and the peak torque at 4250rpm, I seriously doubt they raced a stock GTS engine at 7000 rpm. Especially since the stock engine is electronically rev limited to 6600 rpm -- how do you race that stock engine at 7000 rpm, even if you specifically want to do so and don't mind the slower lap times?!
One or more of your above claims are not true. In two posts, you have demonstrated your tendency to just make stuff up and post that made up stuff with authority.
I could get into the pickup uncovering angles/g-forces per direction, but I am not going to bother.
Claims 1 and 2 imply that it was a GTS engine. If you look at the Service Info Tech 92, you'll see the GTS power and torque curves on page 1-2 and the GTS gear ratios on page 3-7. Given the peak power being produced at 5700 rpm and the peak torque at 4250rpm, I seriously doubt they raced a stock GTS engine at 7000 rpm. Especially since the stock engine is electronically rev limited to 6600 rpm -- how do you race that stock engine at 7000 rpm, even if you specifically want to do so and don't mind the slower lap times?!
One or more of your above claims are not true. In two posts, you have demonstrated your tendency to just make stuff up and post that made up stuff with authority.
I could get into the pickup uncovering angles/g-forces per direction, but I am not going to bother.
06-18-2010, 08:19 PM
#117
Nordschleife Master
Thread Starter
GTS dyno graph from factory ends at 6250 rpm and the car has electronic limit at 6600 rpm (+/- 20 rpm). I don't have the data to prove it (and I am not going to start making up stuff on the spot), but I would guess that a completely stock GTS will make less power at 7000 rpm (if it would run there, which it doesn't) than at 5000 rpm.
Depending on the HP curves, it might make a lot of sense to run to 7000rpm, even if the peak HP is at 5700rpm. the gains might be slight, but there would certainly be advantages, unless the fell off so dramatically that there was less hp at 7000hp than there would be at 5000rpm, which would be the shift point. Which certainly could be possible. doesnt the GTS run to like GT engine speeds too, which is set at 6800rpm as the limit, or does it limit the engine at 6600rpm like the stock S4?mk
06-18-2010, 08:24 PM
#118
Rennlist Member
If so, then certainly it would be foolish to shift at 7000rpm . For my stroker engine, it would be foolish as well, to go over 6600rpm, if I could. if I could, it still would pay a little, but not much.
I thought the GTS had the same ECU as the GTS, but I guess it doesnt.
solve all the problems. just shift, when you should, at near 6400rpm or less.
mk
I thought the GTS had the same ECU as the GTS, but I guess it doesnt.
solve all the problems. just shift, when you should, at near 6400rpm or less.
mk
GTS dyno graph from factory ends at 6250 rpm and the car has electronic limit at 6600 rpm (+/- 20 rpm). I don't have the data to prove it (and I am not going to start making up stuff on the spot), but I would guess that a completely stock GTS will make less power at 7000 rpm (if it would run there, which it doesn't) than at 5000 rpm.
06-18-2010, 08:34 PM
#119
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just checked my dyno runs. you are absolutely right. For me, and Im GLAD I checked and studied the dyno runs, it barely pays to shift past 6200rpm let alone up to 6600rpm. 6400rpm is my new redline, and its performance, NOT saving the engine.
now, i dont think there is a problem with oiling with speeds below 6400rpm.
now, i dont think there is a problem with oiling with speeds below 6400rpm.
06-18-2010, 09:30 PM
#120
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So what you are telling me is that, (1) a stock engine was raced for a season without failure, (2) this completely stock engine had a GTS baffle, (3) the engine was raced at 7000 rpm
Claims 1 and 2 imply that it was a GTS engine. If you look at the Service Info Tech 92, you'll see the GTS power and torque curves on page 1-2 and the GTS gear ratios on page 3-7. Given the peak power being produced at 5700 rpm and the peak torque at 4250rpm, I seriously doubt they raced a stock GTS engine at 7000 rpm. Especially since the stock engine is electronically rev limited to 6600 rpm -- how do you race that stock engine at 7000 rpm, even if you specifically want to do so and don't mind the slower lap times?!
One or more of your above claims are not true. In two posts, you have demonstrated your tendency to just make stuff up and post that made up stuff with authority.
I could get into the pickup uncovering angles/g-forces per direction, but I am not going to bother.
Claims 1 and 2 imply that it was a GTS engine. If you look at the Service Info Tech 92, you'll see the GTS power and torque curves on page 1-2 and the GTS gear ratios on page 3-7. Given the peak power being produced at 5700 rpm and the peak torque at 4250rpm, I seriously doubt they raced a stock GTS engine at 7000 rpm. Especially since the stock engine is electronically rev limited to 6600 rpm -- how do you race that stock engine at 7000 rpm, even if you specifically want to do so and don't mind the slower lap times?!
One or more of your above claims are not true. In two posts, you have demonstrated your tendency to just make stuff up and post that made up stuff with authority.
I could get into the pickup uncovering angles/g-forces per direction, but I am not going to bother.
The S4 GT engines immediately prior were raced to 7200 rpms, despite the peak output being at 6600 rpm and max torque at 4500 rpm (Gruppe H).
Stated modifications to the S4 racing engines which would come under tuning were the use of a pressure limiting (to 3Bar) valve to the heads (from the 944 S2). This slowed oil throughput and the volume of oil in the heads and had the effect of increasing the oil level in the sump. The mentioned modifications to the sump using sheet metal aluminum most likely refers to the subsequently introduced GTS baffle.
* When a former Chrysler engineer did tuning on the Dodge 2.4 for road racing he simply disabled the factory rev limiter and took the engine from a previous limit of 6200 rpms to happily running it at 7500 rpms -- and this is a fairly long stroke engine. So -- whether you realize it or not -- running stock stroker engines above their previous redlines is not so unusual.
The GTS engine was raced in the GTR for almost a complete season without failure and another engine was obtained with the same tuning done to it.
All this aside, you're simply in a bit over your head technically and grasping at any and all straws to try to avoid answering the questions.
You keep appealing to Occams Razor despite the very well established fact that demanding parsimony as an arbitor in answers is a logical and empirical fallacy. It is a guide for rational thinking -- not a rule for rational thinking.
You throw aeration out the window despite it being a well established physical characteristic of lubricating oil. What is that? Do you really think you're helping people with that?