 |
|
We recently had a test day at Thunderhill and given all the various oil pressure / crank scraper debates thought we’d post our data so people can see exactly what the oil pressure looks like around the track.
Using AiMs RS2 analysis software we created a track report that shows a rainbow graph of the oil pressure and RPM around the track.
We currently are running:
A graph of rpm and OP would be better. That allows a person to quickly see odd OP’s.
What was your oil temp and how exactly do you have your sensor installed?
Swepco’s supposed to be really good oil. Was this a low visc experiment?
Ranger wrote:
I find the track map to be helpful (if I am reading it right) notwithstanding the counter-intuitive color coding (red=good, green/blue=bad).
Assuming you were racing in the direction of the arrow, low OP appears to occur mostly under braking. There is the one long infield horseshoe where OP dips into the 20s towards exit, but that one has me stumped. I thought left turns were supposed to cause low OP due to oil climbing the wall?
Interesting graphical representation. Can you add RPM at the low OP points?
I like the graph, as we’ve all been taught or have been teaching for years, it’s under braking that the largest forces are bring applied to the car, i.e. your brakes are more effective than your tires or motor at applying g’s. So to my mind it makes sense that OP may dip under braking as much as or more than it might under cornering or acceleration…
Good stuff… Maybe I will get the oil pan in addition to the scraper.
Ranger -
We are going to mount the temp sensor in the oil level sensor location, but haven’t gotten to it yet. We should have that soon. We have the pressure sensor mounted where the stock pressure senor was mounted.
Here is an example pic of the pressure sensor mounting:
We were doing other testing work but thought this would be good to post for everyone.
Steve,
With RS2 we can slice and dice the data many ways. I’ll post a few other representations of this data later today. The color band is fully configurable based on preferences so it’s entirely possible to make red “bad” and green “good”
For those who like a scatter plot representation I’ve created one and also included GLAT.
dgorman wrote:
[quote]Ranger -
We are going to mount the temp sensor in the oil level sensor location, but haven’t gotten to it yet. We should have that soon. We have the pressure sensor mounted where the stock pressure senor was mounted.
Here is an example pic of the pressure sensor mounting:
We were doing other testing work but thought this would be good to post for everyone.[/quote]
Consider remoting your pressure sensor. Heat and vibration are hard on them. Also, the remoted sensor makes it easy to put in a second device like a pressure switch to illum a big red light. Your dash can probably do that on it’s own but most folks don’t have your cool system.
Oil temperature. If you are going to measure oil temperature in the pan I’d put a bung near the bottom of the left side of the pan. The oil level sensor might be too high of a location. Sure, the oil gets that high when the car is parked, but I wonder how often the probe would be uncovered when half the oil load is flying around the engine.
Very Interesting Dan. But don’t get too caught up in the data. Get that car on the track and race it! That iiissss what you built it for. I don’t have any guages that work, and I don’t want any!
I can’t seem to kill my motor. It has 250k on it and it does not burn a drop of oil. Tranny did finally start spittin’ oil on to the clutch and so STR replaced both for me. But that darn BMW motor won’t quit. I might have the lowest HP/TQ in the group but the motor just keeps going and going.
My oil pressure probably gets that low, or lower I guess, but man these motors just don’t want to die.
Eventually I will put a new motor in and it probably won’t last a season so I hate to mess with it.
If your VM Motor is like Steves you will be flyin’ ! I hope we see you at THill in August.
the Shoe wrote:
[quote]Very Interesting Dan. But don’t get too caught up in the data. Get that car on the track and race it! That iiissss what you built it for. I don’t have any guages that work, and I don’t want any!
I can’t seem to kill my motor. It has 250k on it and it does not burn a drop of oil. Tranny did finally start spittin’ oil on to the clutch and so STR replaced both for me. But that darn BMW motor won’t quit. I might have the lowest HP/TQ in the group but the motor just keeps going and going.
My oil pressure probably gets that low, or lower I guess, but man these motors just don’t want to die.[/quote]
That made me burst out laughing. I could turn your motor into scrap metal in a weekend. Mighty #9 is making it’s debut this weekend. 20 months, 9 engines.
I should pull my motor out and ship it to you. It would be interesting to see who wins, you or the motor 
There’s this guy in Germany, we call him Fritz… He’s the worlds most infuriating car builder/mechanic/engineer… He’s designed the 911, the 325, all the M3’s and 5 & 6 series and is “responsible” for the 914…
Fritz has put together some engines that dance in the face of danger, like the 530 motor that lived for 300,000 miles, where as most of them were dead at 30,000, he built the auto tranny in my 92 325 and it’s going strong now at 280,000 miles… But he also built the majority of them that dies at 90,000 miles.
Fritz is at once the best and worst of everything mechanical and German…
While Ranger is his victim, you are his benefactor…
There is a rule though, try not to outdo Fritz, he possesses magic and will destroy your will to meddle.
Sarcastically yours,
Kieran