Temp and Timimg
Racer
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Drifting
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From: az
Originally Posted by C64BOB
Le Mans Master
Joined: Aug 2004
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From: Monroe Township New Jersey
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
St. Jude donor in memory of jpee '14
Originally Posted by SpinMonster
The intake air temperatures measured at the MAF is what the car uses to start pulling timing in addition to running temperature. There are 2 tables. The biger issue of the two is that if the IAT is over 86 degrees it starts to pull timing. While you think that would be the temperature on an 86 degree day, think again. The Iat sensor is located in the mAF which is conveniently sitting on top of the upper radiator hose. On my last tuning day the night temps were 64 degrees ambient and my car was logging 100 IAt for 8 minutes at 60+ mph. Heat soak stores the heat in the tubing and palstic MAF for 8-10 minutes. At traffic lights it went as high as 140. The actual intake air temps into the motor would be ambient but the car goes by the IAT reading.
To answer the original question at 100 degrees IAT, the car is pulling 5-6 degrees and at 140 (waiting at the tree at a track) it is pulling 11 degrees by the stock table. Now if the coolant temps go up high, that pulls from another table but I dont have HPtuners here to reference the amounts and temps it occurs at from memory.
To answer the original question at 100 degrees IAT, the car is pulling 5-6 degrees and at 140 (waiting at the tree at a track) it is pulling 11 degrees by the stock table. Now if the coolant temps go up high, that pulls from another table but I dont have HPtuners here to reference the amounts and temps it occurs at from memory.
Hey Spin,
You previously posted on this issue and some one posted a copy of the HPtuners screen showing the IAT temps and timing. I can't find it can you? thanks
Drifting
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From: az
Originally Posted by Tommy D
Hey Spin,
You previously posted on this issue and some one posted a copy of the HPtuners screen showing the IAT temps and timing. I can't find it can you? thanks
You previously posted on this issue and some one posted a copy of the HPtuners screen showing the IAT temps and timing. I can't find it can you? thanks
Tech Contributor
Joined: Mar 2003
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Originally Posted by cbrf4i1
i have a copy of it, it was from bretthunter, that hptuner screen didn't show heat soak any where near spin situation. once he got moving within 3 minutes the iat was pretty much ambient. i don't have a way to posted a picture, i can email to you if you want to post to this thread.
If anyone has a HPtuners cable, I will email a log file and you can watch it in real time.
Drifting
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From: az
brett, where are you? i went to look at his graph again, he stated the ambient temp was around 40*, after not moving for 3 minutes iat shot up to 100*, he then went wot up to 120 mph, with in 1 minutes iat went from 100* down to 60*, it continue to come down to but not as fast (he is slowing down to cruising at 60-70mph now) 5 minutes later iat showing 47*. i think that is pretty close to ambient temp(40*). when he did his data logging i am pretty sure he didn't relocate iat. correct me if i am wrong, brett. he was using the beta version, not sure if that makes a difference or not. spin, any ways, don't kill the messager, just responsing to what tommy d was asking.
Tech Contributor
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Originally Posted by cbrf4i1
brett, where are you? i went to look at his graph again, he stated the ambient temp was around 40*, after not moving for 3 minutes iat shot up to 100*, he then went wot up to 120 mph, with in 1 minutes iat went from 100* down to 60*, it continue to come down to but not as fast (he is slowing down to cruising at 60-70mph now) 5 minutes later iat showing 47*. i think that is pretty close to ambient temp(40*). when he did his data logging i am pretty sure he didn't relocate iat. correct me if i am wrong, brett. he was using the beta version, not sure if that makes a difference or not. spin, any ways, don't kill the messager, just responsing to what tommy d was asking.
Drifting
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From: az
from looking at his graph, he went up to 120 mph and came right back to highway. (within the same minute) at that point the iat was at 60 then 4 minutes later at that high way speed iat went down to come down to 47*. i really don't expect it to be exactly ambient, i would be happy to be a few degrees (that is what i meant when i stated "pretty much ambient") considering no one drives with the hood open.
spin, when you did your data log, was you car hot already? maybe brett's car was stone cold when he was data logging.
spin, when you did your data log, was you car hot already? maybe brett's car was stone cold when he was data logging.
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Drifting
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From: az
Tech Contributor
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Originally Posted by cbrf4i1
from looking at his graph, he went up to 120 mph and came right back to highway. (within the same minute) at that point the iat was at 60 then 4 minutes later at that high way speed iat went down to come down to 47*. i really don't expect it to be exactly ambient, i would be happy to be a few degrees (that is what i meant when i stated "pretty much ambient") considering no one drives with the hood open.
spin, when you did your data log, was you car hot already? maybe brett's car was stone cold when he was data logging.
spin, when you did your data log, was you car hot already? maybe brett's car was stone cold when he was data logging.
Tech Contributor
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Using the patch wire to reduce this timing issue is a bad idea. The IAT sensor needs to be in the system or thereis a great chance of knock. The better solution is to put an aftermarket sensor down stream of the air intake. The intake tubing will heat the air so it can never be ambient. You can reduce the chances of too much timing being pulled by simply tuning in the correction yourself. Make the table allow zero degrees pulled at 86 and reduce it in half. Drive around hard and log in hot weather to check for knock retard. If you dont have any then the rediced timing pull is safe and still compensates in super hot air to protect the car. It makes no sense to bypass the sensor with a patch wire since it can be deleted for free in a tune by entering all zero's in all fields of the IAT spark table.
Ultimately if you did over compensate, the car still has knock sensors to protect you. This area of tuning is the best place to pick up power in a tune especially for southern cars that have already been maximized in the air fuel area. In the texas heat you will be always at 11 degrees pulled if you dont do this one.
Ultimately if you did over compensate, the car still has knock sensors to protect you. This area of tuning is the best place to pick up power in a tune especially for southern cars that have already been maximized in the air fuel area. In the texas heat you will be always at 11 degrees pulled if you dont do this one.
Safety Car
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From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
Originally Posted by SpinMonster
In reality you smply adjust the table higher rather than bypass it with a resistor. You can make it not pull timing untill the car hits 100+ rather than defeat the protection altogether. You can also input any value such as 5 degrees pulled instead of 11. The point is that the tune still has to provide protection against temp induced knock. The C6 is way overdone though.
a cooler air charge will produce more power.
some attempt to acomplish this via the thermostat, some use cai, some use 'tuning utilities', some use nos, and some just don't care.
Le Mans Master
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From: Monroe Township New Jersey
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
St. Jude donor in memory of jpee '14
Originally Posted by cbrf4i1
Hey Thanks
I asked Brett in another thread if he coud post one at an idle so that we can actually see the amount of heat soak on a stock C6. Then all we need is one with the IAT protected from the heat and check the difference. This was Spins idea in that thread you found.
Brett posted a graph of a stock C6 which indicated the coolant temp at approximately 201 degrees with the IAT at approximately 78 degrees on a 80 -86 degree day but the car was going 132 MPH. We need to see what the actual heat soak is caused from at an idle. (proximity to radiator, non moving hot air, heat from the throttle body or all of the previously mentioned. In any case Brett agrees with Spin regarding the vararam and the location of the IAT
Le Mans Master
Joined: Aug 2004
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From: Monroe Township New Jersey
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
St. Jude donor in memory of jpee '14
Originally Posted by SpinMonster
Good point you make there. The log was made after 1 hour of tuning and was very hot. It was a summer night and if the ambient temps are 80 then 10 degrees at normal driving puts the IAT at 90 which is definitely pulling timing and it is 4 degrees at 86 and 7 degrees at 113. I regularly saw 120-140 stopping at lights which is 11 degrees pulled. Horrendous power losses at those temps. A 160 degree thermo. assures not going into the coolant temp timing pull situations. The coolant temps at 212 or lower are without timing issues. Regular stopping and going kept the car at 100 IAT.
Drifting
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From: az
Originally Posted by Tommy D
Spin, I should have read your post first. Then it seems we are all chasing our tails looking to manage the coolant temperature when we should be more concerned with the IAT temp.
http://forums.corvetteforum.com/show...post1557370135
Le Mans Master
Joined: Aug 2004
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From: Monroe Township New Jersey
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
St. Jude donor in memory of jpee '14
Originally Posted by cbrf4i1
tommy, you really want to watch both of them, timing retard could alse be cause by high ect. brett posted this thread yesterday, in that session he logged over 20 minutes of driving condition. again he, doesn't seem to have the same heat soak issue as spin. you will noticed within a few minutes the iat comes down quit a bit. 115* down to 95* (78* ambient / 75-80mph for a little over 100 seconds). again, he might have started his data logging without any heat soak issue. on the other hand, spin mention his car was really hot when he started his log, maybe once heat soak happens it is really hard to get rid off.
http://forums.corvetteforum.com/show...post1557370135
http://forums.corvetteforum.com/show...post1557370135
Yes but according to Spin timing does not get pulled until the coolant temp is approximately 212. I was wondering why tuners want the car running approximately at 185 degrees and utilize a 160 stat with adjusting the fans. It seemed to me that a larger radiator with a higher stat and some adjustment to the fans should really do the trick.
Usually too low a stat or no stat on a stock radiator and the coolant goes through the radiator too quickly and does not lose enought heat. But I am beginning to think that the lower stat with the right fan adjustment allows the coolant to circulate & cool quicker therefore helping reduce the IAT heat soak.
I guess if I really want to play again it is very shortly going to be time to get knee deep in HP tuners
Drifting
Joined: Sep 2004
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From: Livingston Texas
Tommy asked me to post some graphs of idling. This is the best I can do for now. I will look through a few more recordings to see if I can find anything better later.
The weather conditions for this run was 77 degrees, Dew point 70 degrees, 30.17/1020.2 hpa.
I cut the graph down to the last 25 minutes or so of the run, earlier in the run the heat soak is not that much of an issue.
BTW this is not HP Tuners but rather an Ease recording.
This is with a Halltech Stinger without the CAI mod, stock stat and the fans adjusted via LS2 Edit.
The weather conditions for this run was 77 degrees, Dew point 70 degrees, 30.17/1020.2 hpa.
I cut the graph down to the last 25 minutes or so of the run, earlier in the run the heat soak is not that much of an issue.
BTW this is not HP Tuners but rather an Ease recording.
This is with a Halltech Stinger without the CAI mod, stock stat and the fans adjusted via LS2 Edit.
Le Mans Master
Joined: Aug 2004
Posts: 5,259
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From: Monroe Township New Jersey
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
St. Jude donor in memory of jpee '14
Originally Posted by Brett Hunter
Tommy asked me to post some graphs of idling. This is the best I can do for now. I will look through a few more recordings to see if I can find anything better later.
The weather conditions for this run was 77 degrees, Dew point 70 degrees, 30.17/1020.2 hpa.
I cut the graph down to the last 25 minutes or so of the run, earlier in the run the heat soak is not that much of an issue.
This is with a Halltech Stinger without the CAI mod, stock stat and the fans adjusted via LS2 Edit.
The weather conditions for this run was 77 degrees, Dew point 70 degrees, 30.17/1020.2 hpa.
I cut the graph down to the last 25 minutes or so of the run, earlier in the run the heat soak is not that much of an issue.
This is with a Halltech Stinger without the CAI mod, stock stat and the fans adjusted via LS2 Edit.
Thank you Brett
Wow, at an idle in one second it goes from 93 to 110.
Drifting
Joined: Sep 2004
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From: Livingston Texas
Originally Posted by Tommy D
Thank you Brett
Wow, at an idle in one second it goes from 93 to 110.
Wow, at an idle in one second it goes from 93 to 110.
Actually it takes 100 seconds instead of just one. Each block on the top graph is 50 seconds.
It's a little hard to read because it is a scan instead of a direct screen shot (haven't setup my new laptop print settings yet).
The majority of my logs including all of my stock runs are on my old laptop. I'll see if I can get it started up and look at some more.
Drifting
Joined: Sep 2004
Posts: 1,551
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From: Livingston Texas
Originally Posted by SpinMonster
Unless he relocated the sensor, it never reads ambient. 10 degrees over was the lowest I see it after a 1/2 hour. 150 down to 65 is not happening in 3 minutes ever.
If anyone has a HPtuners cable, I will email a log file and you can watch it in real time.
If anyone has a HPtuners cable, I will email a log file and you can watch it in real time.
I have just reinstalled my stock airbridge and completed roughly 150 miles of driving since reflashing. I hope to get the car out tomorrow if this rain will stop.