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This weekend at Shenandoah Circuit I ran my Aim Solo DL as well as the PDR. Below is a raw cut and paste from yesterday's sessions with lap time, speed, coolant, oil, and intake air temp max. The high temp was 87F and sunny.
A couple interesting things. The first is that the vehicle speed is a little on the conservative side whereas most every other vehicle I've seen has been optimistic on indicated speed. I commented on this once before but folks comparing top speed indicated from say a C6Z to a C7Z need to realize that there is a combined error between the two that can result in 10 or more MPH difference.
The other is to look at the IAT. You'll see that when I pitted in and turned off the car the IAT shot up and stayed that way when I started the car back up until it got moving. Once moving the temps dropped rapidly. Usually my stops were pretty short and were enough to get gas, a drink, and use the facilities.
My lap times were all over the place. In some cases this was traffic, others is was the tires going off, or just me wanting to cool it for a lap or two.
Except why did those IAT's jump up only for a bit?
Originally Posted by Poor-sha
The other is to look at the IAT. You'll see that when I pitted in and turned off the car the IAT shot up and stayed that way when I started the car back up until it got moving. Once moving the temps dropped rapidly. Usually my stops were pretty short and were enough to get gas, a drink, and use the facilities."
Good Reporting Sean,
I've seen the same thing on my GS, especially in daily driving I can see a temp difference of about 30~40* at certain stop lights. After about 5mins of driving @ at least 30MPH my intake temps will settle at about +10* of ambient. My belief is that corvette hood lines are so low that the intake will heat soak in a couple minutes with without flowing air.
Anyway, I read guys are currently looking at trapped air in the SC as being the culprit in the latest MT thing.
Trapped heat would even jive with Tadges math and the air flow/aero scenerio!
Can you explain to us what occurred between run 5, laps 16, 17 and 18?
What i am wondering about is the ECU_oil_T delta between laps.
I guess what i see here is: Lap times and ECU_oil_T are not inversely proportional. Specifically with lap 17, why am i not seeing a corresponding drop in ECU_oil_T for that given lap time: 1.53.197?
You may have demonstrated the anomaly here in your revision!
How about the new radiator cooling arrangement is causing some of those spikes?
Has anyone ever had this setup before in a SC? The Camaro SC has much more air going in all the way around!
I'm not sure what exactly you're referring to but I believe Truth clarified already. The cooling system is bone stock other that M1 15W50 oil. That includes the same coolant mix that left BG in December.
The IAT temp spike correspond to laps where I just started or stopped the car. If you look at the actual graph you will see it spike as soon as the RPM goes to 0 and then it starts high. Below is a capture of a restart and back out on track with a hot car.
Can you explain to us what occurred between run 5, laps 16, 17 and 18?
What i am wondering about is the ECU_oil_T delta between laps.
I guess what i see here is: Lap times and ECU_oil_T are not inversely proportional. Specifically with lap 17, why am i not seeing a corresponding drop in ECU_oil_T for that given lap time: 1.53.197?
Thanks for catching that. That is precisely why I wanted to post the raw data. It took me a bit to correlate this with PDR video but here is what was happening:
5/15 - normal other than being stuck behind a Miata for a bit.
5/16 - I caught a friend/student in his C7 Z51 and wanted to follow him around a bit to give him feedback on his lines. I was staying pretty close up behind him other than when he was offline.
5/17 - I passed but slowed so he could follow my lines.
Thanks for catching that. That is precisely why I wanted to post the raw data. It took me a bit to correlate this with PDR video but here is what was happening:
5/15 - normal other than being stuck behind a Miata for a bit.
5/16 - I caught a friend/student in his C7 Z51 and wanted to follow him around a bit to give him feedback on his lines. I was staying pretty close up behind him other than when he was offline.
5/17 - I passed but slowed so he could follow my lines.
Thanks. This is the info i was after. Could you please post more PDR video for these sessions? I am totally a PDR junkie.
I think I can see why your car doesn't overheat while the car overheats in the hands of many others. It is not unusual to see a difference of 16 seconds between some of your laps in the same session. You are effectively running some cooling laps. Even if your fastest lap is fast by any standard the 16 second lags in some of the other sessions are more than enough to cool the car. At Laguna Seca which is a similar 1:40 track for the better advanced drivers, a 16 second difference puts you in the beginner group.
It is highly unusual for me to run a difference of more than 8 seconds. You guys must be getting a lot of traffic on track, similar to the lower groups. My car also would not overheat if I oscillated between advanced and beginner lap times.
I think I can see why your car doesn't overheat while the car overheats in the hands of many others. It is not unusual to see a difference of 16 seconds between some of your laps in the same session. You are effectively running some cooling laps. Even if your fastest lap is fast by any standard the 16 second lags in some of the other sessions are more than enough to cool the car. At Laguna Seca which is a similar 1:40 track for the better advanced drivers, a 16 second difference puts you in the beginner group.
It is highly unusual for me to run a difference of more than 8 seconds. You guys must be getting a lot of traffic on track, similar to the lower groups. My car also would not overheat if I oscillated between advanced and beginner lap times.
Totally agree. M7 running 8/10ths should never overheat.
I think I can see why your car doesn't overheat while the car overheats in the hands of many others. It is not unusual to see a difference of 16 seconds between some of your laps in the same session. You are effectively running some cooling laps. Even if your fastest lap is fast by any standard the 16 second lags in some of the other sessions are more than enough to cool the car. At Laguna Seca which is a similar 1:40 track for the better advanced drivers, a 16 second difference puts you in the beginner group.
It is highly unusual for me to run a difference of more than 8 seconds. You guys must be getting a lot of traffic on track, similar to the lower groups. My car also would not overheat if I oscillated between advanced and beginner lap times.
Where is there a 16 second spread here?
Lap 1 2:28.891
Lap 2 1:56.214
Lap 3 1:46.240
Lap 4 1:51.528
Lap 5 1:44.289
Lap 6 1:43.760
Lap 7 1:47.086
Lap 8 1:45.071
Lap 9 1:44.702
Lap 10 1:43.982
Lap 11 1:46.116
Lap 12 1:43.353
Lap 13 1:44.788
Lap 14 1:45.923
Lap 15 1:44.299
Lap 16 1:43.863
Lap 17 1:45.719
Lap 18 1:40.996
Lap 19 1:41.183
Lap 20 1:40.099
Lap 21 1:42.572
Lap 22 1:45.911
Where is there a 16 second spread here?
Lap 1 2:28.891
Lap 2 1:56.214
Lap 3 1:46.240
Lap 4 1:51.528
Lap 5 1:44.289
Lap 6 1:43.760
Lap 7 1:47.086
Lap 8 1:45.071
Lap 9 1:44.702
Lap 10 1:43.982
Lap 11 1:46.116
Lap 12 1:43.353
Lap 13 1:44.788
Lap 14 1:45.923
Lap 15 1:44.299
Lap 16 1:43.863
Lap 17 1:45.719
Lap 18 1:40.996
Lap 19 1:41.183
Lap 20 1:40.099
Lap 21 1:42.572
Lap 22 1:45.911
compare lap 20 with lap 2: 16 second difference.
If this is the same course, a near stock S2000 seems to do it in 1:40 too. Intake and exhaust is only good for 20 hp on that car and the rear tires are only 255s.
lol...what?
How does running a :56 warmup lap effect ECT and EOT ~20+ minutes later when he ran a couple of :40's and a :41 and the temps were 225/262?
S.
To be fair, SBC ran his Z06 to nowhere near it's potential either (1:44 lap time at Laguna as I recall in cooler weather) and it overheated (in warmer weather).
I still think some issues are related to individual cars and some are exacerbated by driving method. SBC's car might be the perfect storm, as he has had numerous issues above what (I think) we've seen with any other car.
S.
Comparing to this video, he is not running his Z no where near its potential, meaning that it should be over heating if ran to the limit?
Yeah, basically all but a few of his laps were on par with this ~260hp nearly stock S2000. No surprise it won't overheat. I bet Spec Miata records on this track are under 1:40.
08-03-2015, 11:58 AM
DATA: ECT/EOT/IAT on Track
M7 running 8/10ths should never overheat. 
