Intake air temp pulling timing help needed

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vp304
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Intake air temp pulling timing help needed

Post by vp304 »

Hey guys have a l67 running on vr commodore ecu.

Is this part pictured below of tuner pro were i would set up how much timing it pulls when the Intake air temps get to high?

Im guessing the 100 - 200 is the boost section
and the -04 to 152 ?
Is the iat temp in Celcius
Attachments
Intake air temp.jpg
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Re: Intake air temp pulling timing help needed

Post by BennVenn »

That looks about right, though charge temp isn't IAT, charge temps is a mix of coolant temp and IAT, you can set up how much of an affect coolant temp has on charge temp using another table.
vp304
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Re: Intake air temp pulling timing help needed

Post by vp304 »

Agh ok thanks for the info Bennvenn. Do you know what that other table is in 11p
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Re: Intake air temp pulling timing help needed

Post by BennVenn »

I'm not sure in 11p, should come up if you search for charge in TunerPro?
vp304
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Re: Intake air temp pulling timing help needed

Post by vp304 »

This is what else come up when i searched in 11p
Attachments
tuner pro charge temp 2023.jpg
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Re: Intake air temp pulling timing help needed

Post by BennVenn »

Yeah that's them.

It's a percentage of coolant which affects 'charge temp'

so if IAT was 0 degrees C, and coolant was 100C, if you had 50% at that particular cell, charge temp would be 50C. If you set them all to 0, charge temp should = IAT.

At lower RPM, manifold and head temps (coolant) have more of an effect on heating the air coming in. As RPM and air density increases, it has less of an effect.
vp304
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Re: Intake air temp pulling timing help needed

Post by vp304 »

Thanks for explaining it bennvenn. I think above my skill level i may make worse by touching lol.
Il just leave what values i put in the
Charge temp advance vs Boost map above and see how i go.
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antus
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Re: Intake air temp pulling timing help needed

Post by antus »

Yeah its because there is no way to measure the temperature of the air in the cylinder when its been compressed. So its an estimation based on the factors that affect it - that is different engines will heat the air differently in the way in due to their cooling systems. It doesn't make a significant difference, the stock values are reasonable, and its very difficult for backyarders to have more correct data to put in there than the OEMs. So usually you would leave it.
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Re: Intake air temp pulling timing help needed

Post by BennVenn »

No problem. I start pulling timing out over 40degrees charge temp. 116 is far too late to pull timing in my opinion but I'm no expert at this.

The location of the IAT in my pulsar gets a whole lot of heatsoak from the head so it always reads at least 10deg hotter than the air running past it. Probably keep that Charge% table stock as antus says unless you have a reason to change it, or you've moved your IAT sensor, or your setup is very different to the car that 11p table was pulled from
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Re: Intake air temp pulling timing help needed

Post by antus »

Charge temp is not IAT temp though, remember the air has been heated in the runners and the cylinders and the compression cycle. You'd expect over 40 degrees charge temp without boost, I think. My understanding of charge temp is its the temp of the air and fuel mix after compression the moment the spark plug fires, and without the guru level tools of the OEMs, we mortals can only hope to guess what that might be, but it makes sense to pull a couple of degrees if its estimated over 116 deg c, on boost.
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