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-   -   Air Intake Temperature (https://www.scoobynet.com/scoobynet-general-1/1054559-air-intake-temperature.html)

bonesetter 01 June 2018 07:12 PM

Air Intake Temperature
 
I have recently been trying a Ecutek ECU Connect dongle which allows you to monitor almost everything the ECU monitors/controls

The most surprising thing (so far) is how long the air intake temperature takes to return to normal after the car has stood hot

I parked the car for 10 minutes with engine off, then drove off with AIT reading 45°C. It took a mile to come back down to normal (29, ambient was 22)

We all know not to give our Scooby's with TMIC's WOT off the lights for this reason, but I really was surprised by 1 mile

hedgecutter 01 June 2018 08:32 PM

On which car? You need the spec C intercooler spray if its the hatch! What did the dongle cost?

trevsjwood 01 June 2018 08:39 PM

There's no way round a parked scoob with a top mount, unless you have water/meth injection. The intercooler would be totally heat soaked and spray wouldn't have that much effect before the damage was done.
Trev

1509joe 01 June 2018 08:43 PM

At last somebody that's by chance noticed it instead of a full scale debate on TMIC vs FMIC :luxhello:

hedgecutter 01 June 2018 08:44 PM

I'm confusing charge temps with intake temps; can wrapping, ceramic coatings or gold foil help?

1509joe 01 June 2018 08:47 PM

MIGHT help but can't see it. It doesn't live in a user friendly spot.

trevsjwood 01 June 2018 08:49 PM


Originally Posted by hedgecutter (Post 12012211)
I'm confusing charge temps with intake temps; can wrapping, ceramic coatings or gold foil help?

OP's talking charge temps. i.e. post intercooler

hedgecutter 01 June 2018 08:57 PM

Bag of ice when you return to the car!

bonesetter 01 June 2018 09:29 PM

Basically, it's a terrible location for an IC

bonesetter 01 June 2018 09:34 PM


Originally Posted by hedgecutter (Post 12012205)
On which car? You need the spec C intercooler spray if its the hatch! What did the dongle cost?

On the hatch - I have a front mount on the Type R so a non-issue

I think the dongle costs ~300. I thought it would be good to use as boost gauge if nothing else, but it 'adds' atmospheric pressure too, so mine shows 2.55 when really the car's boost is 1,55 bar.

Coolant temp is good to see, but predictable, and you can see torque too.

Can't see oil temperature, which if you could would clinch it for me

1509joe 01 June 2018 09:44 PM


Originally Posted by bonesetter (Post 12012228)
On the hatch - I have a front mount on the Type R so a non-issue

I think the dongle costs ~300. I thought it would be good to use as boost gauge if nothing else, but it 'adds' atmospheric pressure too, so mine shows 2.55 when really the car's boost is 1,55 bar.

Coolant temp is good to see, but predictable, and you can see torque too.

Can't see oil temperature, which if you could would clinch it for me

There's no oem oil temp sensor that's why. You'd have to fit a gauge for that unfortunately.

jazzyjembreaze 02 June 2018 08:56 AM

Not exactly a accurate reading what you want is something like I have in the for sale thread from PLX devices, AIT charge temps really need a probe plumed in for spot on readings , I would suspect your actual readings would be even higher if your getting those figures from a ECU or PSi3 without sensors added
Regards/ il bump the for sale thread to the top so you can see what it is

trevsjwood 02 June 2018 09:39 AM

I was surprised at the 45c AIT on drive off after being stood, thought it would have been in the mid 60 degree's.
Trev

jazzyjembreaze 02 June 2018 10:16 AM

It will be , that’s what I’m saying , not accurate

bonesetter 02 June 2018 11:22 AM


Originally Posted by trevsjwood (Post 12012272)
I was surprised at the 45c AIT on drive off after being stood, thought it would have been in the mid 60 degree's.
Trev

mid 60's... that really is shocking

Still, I think it accurate for the cooling down reading/duration?

trevsjwood 02 June 2018 12:02 PM


Originally Posted by bonesetter (Post 12012291)
mid 60's... that really is shocking

Still, I think it accurate for the cooling down reading/duration?

a heat soaked intercooler would take a while to get back to normal and of course if you plant it the turbo adds a whole lot more heat, my MD321T pushes out around 130c at 1.6 bar.
The parked up car after driving is the worst case scenario for a TM, it does do better with the engine running as the turbo pulls air through even at low rev's.
Trev

SmurfyBhoy 04 June 2018 09:18 AM

https://cimg9.ibsrv.net/gimg/www.sco...128cfa9a6.jpeg


TMIC or FMIC

Still get stupidly high IAT if sat still for long,

More so if you have a cone filter in the bay,

Here's a log of my Blob Sti at strip with HDI FMIC & RCM Cone,

Que for around 15 mins creeping up to line stop/start traffic.

Water spray won't do jack in this case

You want a proper sealed off intake taking in ambient air from outside, anything less is just a compromise.

SmurfyBhoy 04 June 2018 09:20 AM

Pretty sure the stock Ecu reads IAT using the MAF sensor

(At least in my 2003 Sti)

1509joe 04 June 2018 10:23 AM


Originally Posted by SmurfyBhoy (Post 12012558)
Pretty sure the stock Ecu reads IAT using the MAF sensor

(At least in my 2003 Sti)

It does but even with a FMIC the ACT at the throttle body soars to 55c+ when stood still but falls alot quicker once on the move. Having said that still wouldn't want to be abusing it for a while.

SmurfyBhoy 04 June 2018 11:32 AM


Originally Posted by 1509joe (Post 12012564)
It does but even with a FMIC the ACT at the throttle body soars to 55c+ when stood still but falls alot quicker once on the move. Having said that still wouldn't want to be abusing it for a while.

That log is from the strip so Launched before reached it's peak temp then dropped for full run,

Still not below ambient temps by end of 1/4

ossett2k2 04 June 2018 11:55 AM

When mapping mafless there are compensation tables to pull timing and add fuel when the ACT is high,I can this not be done when mapping with maf?

SmurfyBhoy 04 June 2018 12:35 PM


Originally Posted by ossett2k2 (Post 12012577)
When mapping mafless there are compensation tables to pull timing and add fuel when the ACT is high,I can this not be done when mapping with maf?

yes same can be done

1509joe 04 June 2018 04:13 PM

Water meth injection helps an awful lot the temps drop as soon as it activates to a sensible level :thumb:

SmurfyBhoy 04 June 2018 04:19 PM


Originally Posted by 1509joe (Post 12012612)
Water meth injection helps an awful lot the temps drop as soon as it activates to a sensible level :thumb:

Would need it on @ idle to bring mine down on the line haha

trevsjwood 04 June 2018 05:06 PM


Originally Posted by SmurfyBhoy (Post 12012615)
Would need it on @ idle to bring mine down on the line haha

idle on the line, that's a laid back approach lol

SmurfyBhoy 04 June 2018 06:19 PM


Originally Posted by trevsjwood (Post 12012624)
idle on the line, that's a laid back approach lol

I wish i could 2-step it everywhere.

fpan 19 June 2018 11:05 AM


Originally Posted by SmurfyBhoy (Post 12012581)
yes same can be done

The map of the car will reduce ignition timing (and perhaps boost?) when IAT are high, still not a good idea to thrash it after sitting stationary for a while though.

SmurfyBhoy 19 June 2018 11:39 AM

https://cimg3.ibsrv.net/gimg/www.sco...0590f94dbe.jpg

Stock ECU has parameters for maf compensation based off IAT, Timing Compensation off IAT & Wastegate Duty,

So if mapped properly there should be no knock or hamr to engine if ragged when IAT are high,

The only downside would be reduced power if any of those compensations are utilised.

TECHNOPUG 19 June 2018 12:09 PM

Surely though the temperature of the probe will always be higher than the transient air temp? The probe is static within the inlet, so will heat up over time. Whereas the air is passing through the same inlet at high speed and therefore won't be exposed to the temperatures for anywhere near as long?

SmurfyBhoy 19 June 2018 12:15 PM


Originally Posted by TECHNOPUG (Post 12014577)
Surely though the temperature of the probe will always be higher than the transient air temp? The probe is static within the inlet, so will heat up over time. Whereas the air is passing through the same inlet at high speed and therefore won't be exposed to the temperatures for anywhere near as long?

As long as the engine is running it would have a constant air flow over it, so wouldn't be as affected

Of course there will be a slight element of heat soak but the sensors will be as insulated as best they can be to stop this effecting things,

Plus if its erring on the slightly high side of things then your always safe


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