Don't sweat the heat...here's some graph data showing..
07-03-2009, 03:28 PM
#16
Parts Specialist
Rennlist Member
Rennlist Member
several reasons... (none of them based on any real data to support them
)for me having the r's higher means when I let off a little in light traffic the speed comes off quicker, so less brakes. I also like it for the instant power when I get a second to give it a little extra fuel. I think (again no data) that these engine prefer to spin faster than to put the torque loads on them at low rpm's - it "feels" faster
I believe having the motor spinning faster puts less stress on the motor than lugging it around...(not suggesting the data above is "lugging" the motor) its just what I think......
this could hurt
07-08-2009, 11:01 AM
#18
Race Director
Thread Starter
Sorry. On vacation and hit deer with car so have not been on of late....
If engine cooled down properly engine coolant should not rise much to be of any concern.
Where there can be "trouble" is if car taken off track "hot" and engine shut down with no time to shed substantial head load that has built up.
As this heat migrates from engine components to coolant coolant temp can rise dramatically though this might be reflected by coolant temp since coolant not flowing past sensor.
Sincerely,
Macster.
07-08-2009, 11:10 AM
#19
Race Director
Thread Starter
As long as car on level ground being in 6th gear (or 5th if 5 speed)...
so which years have OBD and when did OBDII replace it ? - I see some of these are not very expensive and might be fun to record certain data for later review.
your rmp was below 3k while traveling at above 70 mph for a long stretch...for me I tend to keep in lower gear to keep the r's up a bit - sometimes I run down the freeway in 4th and as long as I dont go over 75 I just keep it there....I almost never hit 6th gear (unless I am having one of those solid red/blue line moments)
I think these are data "points" not real time rmp logs - if I draw a line at 3k rpm, you only have about 20% of your run above that line. I assume that is either because it doesnt record real time or you just dont rev the motor thru the gears as we would see more spikes from shifting - right ?
your rmp was below 3k while traveling at above 70 mph for a long stretch...for me I tend to keep in lower gear to keep the r's up a bit - sometimes I run down the freeway in 4th and as long as I dont go over 75 I just keep it there....I almost never hit 6th gear (unless I am having one of those solid red/blue line moments)
I think these are data "points" not real time rmp logs - if I draw a line at 3k rpm, you only have about 20% of your run above that line. I assume that is either because it doesnt record real time or you just dont rev the motor thru the gears as we would see more spikes from shifting - right ?
Data is real time, well all data but speed data is sampled at 5 second intervals. Speed data sampled at 1 second intervals.
This may be why rpms don't quite follow speed.
OBD I came before OBD II -- sorry to state the obvious -- but I don't know when OBD I was required, what year it first appeared. I know OBD II required starting in 1996 (USA cars and light duty trucks).
Sincerely,
Macster.
07-08-2009, 12:36 PM
#21
I don't see no filtering (or "smoothing" per layman's terms), I doubt the ECU has some sort of DSP in place just for coolant temps -- why would it?
I'm ordering one of those!
07-08-2009, 01:28 PM
#23
Race Director
Thread Starter
Yep. Hit deer outside of Ely NV. I was alone. No injuries. Car ...
suffered some damage. Looks bad of course, but nothing major. Pic on the 996 Turbo section in a message I posted the other day.
Car back in Livermore at body/repair shop getting estimate as I type.
I'm in Limon CO ready to head to Denver airport return rental car and see about getting flight to Oakland.
Sincerely,
Macster.
Car back in Livermore at body/repair shop getting estimate as I type.
I'm in Limon CO ready to head to Denver airport return rental car and see about getting flight to Oakland.
Sincerely,
Macster.
07-08-2009, 01:32 PM
#24
Race Director
Thread Starter
No. What you are seeing in graph of coolant and rpm is device....
Yes, I agree. The A/D converter itself has a granularity/resolution limitation, which clearly shows in the graphs.
I don't see no filtering (or "smoothing" per layman's terms), I doubt the ECU has some sort of DSP in place just for coolant temps -- why would it?
I'm ordering one of those!
I don't see no filtering (or "smoothing" per layman's terms), I doubt the ECU has some sort of DSP in place just for coolant temps -- why would it?
I'm ordering one of those!
Well, something's got to have an AD/converter cause coolant sensor emits voltage, not digital signal. Ecu probably has many AD/C present. Microprocessor in CarChip has at least one with 8 (or 16? I forget number now and can't look it up) channels.
AD/C common on microprocessors and especially Ecus cause so many inputs to Ecu are in voltages: coolant temp, air temp, O2 sensors, etc.
Sincerely,
Macster.
07-08-2009, 01:35 PM
#25
Race Director
Thread Starter
Thought about it but do not have time. Others have (Jake Raby....
The device I was using is not general purpose/expandable data logger but mainly geared towards trip recognition and data logging associated with trips, speed mainly. OBD II data logging added feature to help fleet customers monitor vehicle population health and provide some diagnostics capabilites when (if) check engine light ever comes on.
Sincerely,
Macster.
