The importance of a good Intercooler VS CAI

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amirza786

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According to JR from KTuner...

ECT1 is Engine Coolant Temperature at the radiator.
ECT2 is post radiator.
IAT is part of the MAF sensor. Pre-intercooler.
IAT2 is post intercooler.
Thanks for correcting that and clarifying
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@amirza786 so what kind of shitty CAI were you running when you did the log you posted? Seems more of a HAI than CAI. It must be behind the radiator picking up hot air off the radiator or something..

I get IATs of 140-150 easily in az. But within seconds of moving it goes down to ambient+10-15f at most.

The intercooler was doing its job but seems like the intake was not helping it at all.
 

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@amirza786 so what kind of shitty CAI were you running when you did the log you posted? Seems more of a HAI than CAI. It must be behind the radiator picking up hot air off the radiator or something..

I get IATs of 140-150 easily in az. But within seconds of moving it goes down to ambient+10-15f at most.

The intercooler was doing its job but seems like the intake was not helping it at all.
Pretty sure that's stock airbox
 


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No wonder.

iats of 143
Ect2 149

sucks air right off radiator.
 

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No wonder.

iats of 143
Ect2 149

sucks air right off radiator.
My logs had stock box with a high flow filter getting 25-30°F over ambient as well. My SRI gets 15-20. What real benefits are gained from this temp difference? :dunno:

Hopefully the gain in flow helps, but I dont have any testing to confirm or deny
 

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Well on subaru platform timing starts being pulled at 104f+ IATs. Then it increases from -0.5 to -1 and -1.5 and so on as IATs increase. At 145 there is probably a -4.5 timing pull. Significant.

But unlike yours my scoop is above and infront of radiator (kind of) so as i start moving and get 30sec of 30mph going my iats are 10-15 above ambient. Also my IMTs (cool charged air) is never below IATs, always +2 or more above air sucked thru maf/airbox. His temps are +40f above ambient which is 103f if i recall and thats under 6psi of boost.

So i am sure honda ecu pulls timing too but perhaps based on IAT2 instead of IAT like my subaru? Then the question is how much timing is being pulled. On subaru a 10f delta can result in 1deg of timing pull.
 
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@amirza786 so what kind of shitty CAI were you running when you did the log you posted? Seems more of a HAI than CAI. It must be behind the radiator picking up hot air off the radiator or something..

I get IATs of 140-150 easily in az. But within seconds of moving it goes down to ambient+10-15f at most.

The intercooler was doing its job but seems like the intake was not helping it at all.
Stock intake, I don't like cai's. It was a hot day that day, I was sitting idling while I was setting up logging, that is probably why you are the seeing high IAT's because heat built up in the engine bay
 

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@amirza786 so what are the IATs usually. In that log you were boosting at 6psi and about 30mph.. mine would have dropped to 110-115 w ambient 103f if boosting and moving. Yours didnt budge from 145-143f. And your ic temps dropped to 110s which means you were moving and it did its job cuz i assume while idling your IAT2 would be equal to IAT no?

Just sitting and idling i can get to 140f with ambient of 70f. But once i move, let alone boost and get to 30mph the IATs drop right away.
 


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@amirza786 so what are the IATs usually. In that log you were boosting at 6psi and about 30mph.. mine would have dropped to 110-115 w ambient 103f if boosting and moving. Yours didnt budge from 145-143f. And your ic temps dropped to 110s which means you were moving and it did its job cuz i assume while idling your IAT2 would be equal to IAT no?

Just sitting and idling i can get to 140f with ambient of 70f. But once i move, let alone boost and get to 30mph the IATs drop right away.
Keep in mind that the part of the log you are seeing is probably a 5 second snapshot of a very big log. Normally my IAT would be just a little above ambient temperature while driving. There was not enough time to exchange the engine compartment with cooler air. For sure though the Intercooler is keeping things cooler as the charged air's heat is being dispersed quickly as it's designed to remove heat even when idle
 

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Oh ok, surprisingly your ECT is still 179 with those runs you mentioned.
ECT is controlled via your thermostat and radiator....it should basically run at 179 during all normal operating. The only time I see it drop below that is when I let off the gas to coast downhill IN GEAR. The reasoning behind that is your car shuts down fuel during that action, therefor your engine has to fire in the cylinders. It cools down pretty quick too. I've seen 10 degree drops or more depending on how long I'm coasting in gear. You can test the theory by coasting in neutral. It will stay right at 179.

Or did I misunderstand and you were surprised it didn't go above 179 during the logs?
 

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ECT is controlled via your thermostat and radiator....it should basically run at 179 during all normal operating. The only time I see it drop below that is when I let off the gas to coast downhill IN GEAR. The reasoning behind that is your car shuts down fuel during that action, therefor your engine has to fire in the cylinders. It cools down pretty quick too. I've seen 10 degree drops or more depending on how long I'm coasting in gear. You can test the theory by coasting in neutral. It will stay right at 179.

Or did I misunderstand and you were surprised it didn't go above 179 during the logs?
Yes you misunderstood, i was surprised that after he said he was doing a few runs his ETC is still around 179. My Fan turns on at 177 degrees and shuts off while coasting.
 

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Yes you misunderstood, i was surprised that after he said he was doing a few runs his ETC is still around 179. My Fan turns on at 177 degrees and shuts off while coasting.
Ah, thanks for the clarification. Interesting thread here.
 

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@amirza786 If the log is good enough to show how intercooler works its good enough for purposes of this discussion too.


So i noticed you also had knocking sensed and timing pulled by 5.5deg then 2.5 as you let go of throttle and out of boost. But IAT is constant at 143. I logged my car today and IATs drop with IAT2s. Its really strange that your (not charged air) but ambient intake air is 143f. The measurement is at maf sensor not post turbo and pre intercooler and you being at 45mph at 5000rpm in 2nd gear means you had to get there thru first at least. On my car the airbox temps or IATs would drop to 10-15f over ambient for sure thru two gears. So to me it still says that it must be sucking engine bay/radiator hot air which is your ect2 temps. It also tells me that tour intercooler is working better than you thought cuz it dropped the charged air (which is IAT+heat from charging it) to 111F.

Also, unfortunately for your setup as well as mine the IATs determine the ignition timing it seem, and while your IAT2s are lower timing is still pulled based on higher IATs. At 143f id expect about 4.5-5 deg pull on my car w any kind of acceleration.
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