Request: air intake temp AIT data
HLI - head light intake FTW 
06-19-2007, 09:32 PM
#45
Elite Member
Thread Starter
iTrader: (5)
Join Date: Jan 2005
Location: Atlanta
Posts: 7,486
Total Cats: 372
Black car FTL :gay:
I think the Link reads a constant 100c if the sensor is bad. But you get some slight variation.
Pull that thing out and put the hair dryer on it with a thermometer for comparison.
I think the Link reads a constant 100c if the sensor is bad. But you get some slight variation.
Pull that thing out and put the hair dryer on it with a thermometer for comparison.
Reply
0
0
06-20-2007, 02:31 AM
#47
Junior Member
Join Date: Dec 2006
Location: Vancouver, BC
Posts: 129
Total Cats: 6
Here's some Hydra logs of my MSM. I have an AEM intake and a BEGI intercooler.
For the first log, I had just been sitting idling so the AIT started a little high. AIT stays steady at ~39-40C and it was around 20C ambient.
For the second log, I was climbing a steep mountain highway in the evening and at about ~15C ambient.
For the first log, I had just been sitting idling so the AIT started a little high. AIT stays steady at ~39-40C and it was around 20C ambient.
For the second log, I was climbing a steep mountain highway in the evening and at about ~15C ambient.
Reply
0
0
06-21-2007, 09:50 AM
#48
Elite Member
Thread Starter
iTrader: (5)
Join Date: Jan 2005
Location: Atlanta
Posts: 7,486
Total Cats: 372
(second log) I see the typical rise in your longest boost section, but definitely heat soak after that run since the AIT rises to 40c right at the end of the boost and remains there. I'm surprised to see the temps that high at 10psi with the BEGI IC- that's 20c over ambient.
I went out last night and made some runs at 8psi (stock wg) with a poor tune (still spanked a 350z). Made four runs- two were low rpm to 7k in fourth, and two were 1-4th gear to ~7k. By then end of those I had my AIT up to 48c. First run is shown below in a power graph (same settings that produce 250/250 from my dyno run). I think this confirms that the AIT compensation's IGN retard is killing top end since this pull only peak at 38c near 7k. The fall off at the end is the knock sensor picking a yet to be identified rattle. I can feel the difference in relative pull after 6k compared to the higher boost (and temp compensation - ign retard) of the 15psi runs. This also explains why the car always feels quicker on the first boosted run.
Curious how others have their IC positioned. Mine is as close as I can get it to the face of the a/c condenser. That's probably a 1/4" gap between the two. The face is pretty much fully exposed to oncoming air. - rob
I went out last night and made some runs at 8psi (stock wg) with a poor tune (still spanked a 350z). Made four runs- two were low rpm to 7k in fourth, and two were 1-4th gear to ~7k. By then end of those I had my AIT up to 48c. First run is shown below in a power graph (same settings that produce 250/250 from my dyno run). I think this confirms that the AIT compensation's IGN retard is killing top end since this pull only peak at 38c near 7k. The fall off at the end is the knock sensor picking a yet to be identified rattle. I can feel the difference in relative pull after 6k compared to the higher boost (and temp compensation - ign retard) of the 15psi runs. This also explains why the car always feels quicker on the first boosted run.
Curious how others have their IC positioned. Mine is as close as I can get it to the face of the a/c condenser. That's probably a 1/4" gap between the two. The face is pretty much fully exposed to oncoming air. - rob
Reply
0
0
06-21-2007, 03:31 PM
#52
Junior Member
Join Date: Dec 2006
Location: Vancouver, BC
Posts: 129
Total Cats: 6
(second log) I see the typical rise in your longest boost section, but definitely heat soak after that run since the AIT rises to 40c right at the end of the boost and remains there. I'm surprised to see the temps that high at 10psi with the BEGI IC- that's 20c over ambient.
) off and see if it makes a difference.I don't have a/c and I haven't tried filling any of the gaps to improve airflow.
Reply
0
0
06-21-2007, 04:22 PM
#53
Elite Member
Thread Starter
iTrader: (5)
Join Date: Jan 2005
Location: Atlanta
Posts: 7,486
Total Cats: 372
What I'm getting at is that if it's 15c ambient, your AIT temp is substantially higher than that at 35c. Are you sure about this? That's before you're in boost? Usually you don't see temps like that until after you're deep into a boosted run. Your second log shows a min. AIT of 24c - so I assumed that you started your run at the min. and then rose to 34c with heat soak bringing it up to 36c after boost ended.
In my case, my IC is always 2c above ambient and only rises about 2c until I hit a peak boost of 15psi around 4500. At that point it's starts a rise for another 16c.
In my case, my IC is always 2c above ambient and only rises about 2c until I hit a peak boost of 15psi around 4500. At that point it's starts a rise for another 16c.
Reply
0
0
06-21-2007, 09:01 PM
#57
Supporting Vendor
iTrader: (33)
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,659
Total Cats: 134
You know I asked that at miata.net a few weeks ago and didn't get a single answer. IIRC, I'm pulling 1 deg timing per 10 deg F after 115. Not knocking now, was before turning on the IAT correction.
Reply
0
0
06-22-2007, 01:57 AM
#60
Junior Member
Join Date: Dec 2006
Location: Vancouver, BC
Posts: 129
Total Cats: 6
What I'm getting at is that if it's 15c ambient, your AIT temp is substantially higher than that at 35c. Are you sure about this? That's before you're in boost? Usually you don't see temps like that until after you're deep into a boosted run. Your second log shows a min. AIT of 24c - so I assumed that you started your run at the min. and then rose to 34c with heat soak bringing it up to 36c after boost ended.
In my case, my IC is always 2c above ambient and only rises about 2c until I hit a peak boost of 15psi around 4500. At that point it's starts a rise for another 16c.
In my case, my IC is always 2c above ambient and only rises about 2c until I hit a peak boost of 15psi around 4500. At that point it's starts a rise for another 16c.
I just looked at the whole log again. I started it shortly after my car was started after work...the coolant was only at 45C. So the AIT was 24C basically from the start...maybe the sensor had heat-soaked in the engine bay for the 8 hours since I had parked it in the morning?
I then drove ~8 city blocks to the highway on-ramp with only a couple very minor boost events. At that point the AIT was already at 32C.
After driving on the highway in traffic for a bit then at the base of the hill the AIT was up to 34C.
After the boosted run up the hill the AIT was at 36C.
So it sure seems that it's really high all the time.
Coasting back down that same hill my coolant went from 95C to 88C but my AIT only went from 34C to 28C. I must be getting hardly any airflow through my intercooler.
Reply
0
0
