IAT’s, How high is too high?

[dreksnot]

Originally Posted by RupertPupkin

Would you always need to run the spray for street application? I’m assuming you do.

Turn the boost controller off and the H2O injection is paused. With the EBC on a working profile for boost, rpm and spray pump duty cycle, why not have it spray while in the street?

[AGP Turbo]

Could be better but if ambient is 100 and you're running 15psi, then 150f is fine. If you were getting that IAT in the winter at 10psi, then you really have a problem.

Indy cars endurance race at 22psi and no intercooler, IAT's over 300 the whole race. Just E85.

[RupertPupkin]

Originally Posted by dreksnot

Turn the boost controller off and the H2O injection is paused. With the EBC on a working profile for boost, rpm and spray pump duty cycle, why not have it spray while in the street?

I was thinking how it runs similar to meth. Just in case the water runs out and the car will run too lean..

[dreksnot]

Originally Posted by RupertPupkin

I was thinking how it runs similar to meth. Just in case the water runs out and the car will run too lean..

I will dial in the tune for street without injection. With the injection, fueling should still be fine, maybe a little more fuel than I'd normally run but okay. I'm not going to max tune with injection as that could be unhealthy lean for the motor if empty water tank. I'm not looking for more power - I'm looking for cooler IAT's so timing doesn't get pulled.

[hillshooter]

Only to brag

104 degrees IAT in the middle of the day, 98 degrees ambient at the top of a 6 second pass.

No methanol, just built right.

[stevieturbo]

Originally Posted by Big Biscuits

I have looked high and low for an answer. Nothing solid. I know some N/A cars can run high iat’s but cool off during a run. What about boosted cars? Mine will hit 150* from 100* in the 1/8th mile.

Depends on fuel, CR, the environment, boost....and how you're reading it. Lots of so called fast IAT sensors...are not fast, so the lag will actually mean the temp can be worse.
And of course what you use it for. Simply running 1/8th mile will never be as risky as say a full mile.

And most typical IAT thermistors don't really read accurately above around 200degF either although you'd hope you're never up there.

Always strive for the coolest air you can. Too high is simply when detonation or engine health poses a problem from it and the tuning you are using for it.

But is hot air alone a problem ? No, sure people run no IC and get away with it. Just ensure anything is built/tuned around how it does run.

[stevieturbo]

Originally Posted by dreksnot

Turn the boost controller off and the H2O injection is paused. With the EBC on a working profile for boost, rpm and spray pump duty cycle, why not have it spray while in the street?

Why have it spray ? I'm traction limited regardless...so using WI for more power on the street is nigh on pointless.

Would also love to see some actual flow/pressure testing on the pump at those various duties.

[stevieturbo]

Originally Posted by hillshooter

Only to brag

104 degrees IAT in the middle of the day, 98 degrees ambient at the top of a 6 second pass.

No methanol, just built right.

The way it should be....that said, I had similar logs maybe 15+ years ago, but that was because the sensor I was using ( as supplied from ecu maker at the time ) was shit and woefully slow.
So intake temps never really rose, but it was only because the sensors was barely responding even by the end of a run when things were cooling down again lol.

[dreksnot]

Originally Posted by stevieturbo

Why have it spray ? I'm traction limited regardless...so using WI for more power on the street is nigh on pointless.

Would also love to see some actual flow/pressure testing on the pump at those various duties.

Well, even on the street and a single 3rd gear pull, I hit high enough IATs to where I'd like to pull timing (see 3rd plot IAT Retard of -4.4*). This is without WI.

[Big Biscuits]

Originally Posted by JANNETTYRACING

If you are seeing that much of a temp delta in that short a distance you need a larger intercooler and larger blower.

You may also look in to moving your air intake, Filter to a cooler location.

Are your headers coated, look for ways to reduce underhood temps.

I would expect to see 50 degrees over a 1/4 mile on a good set up.

But there are many factors that effect this number and you need to take all things in to consideration.

There is no denying cooler is better, Cooler Denser air can burn more fuel on each combustion cycle.

Pissing on the fire is a bandaid for the real problem.

Ted.

The ESS intercooler and G3x are plenty large enough. The High IAT is due to the wastegate setup. It has a 95mm pulley and I have it bleeding boost Off at 15 psi. It is a lot more fun than just a 110 or 100 mm pulley. Lots of low end power in comparison. Trade off is heat. With E85 and a good tune, I was looking for an IAT Scale to keep an eye on. If it was going to be in a dangerous IAT range, I would pulley up to the 100mm and let it go full tilt with no waste gate.

[Big Biscuits]

Originally Posted by AGP Turbo

Could be better but if ambient is 100 and you're running 15psi, then 150f is fine. If you were getting that IAT in the winter at 10psi, then you really have a problem.

Indy cars endurance race at 22psi and no intercooler, IAT's over 300 the whole race. Just E85.

It was around 80* but lots of waiting in the staging lines to get a run. Log started at 102* after a good burnout and topped out at 150*. Dropped quickly after the run though.

Originally Posted by hillshooter

Only to brag

104 degrees IAT in the middle of the day, 98 degrees ambient at the top of a 6 second pass.

No methanol, just built right.

Nice! Something to work toward.

Originally Posted by stevieturbo

Depends on fuel, CR, the environment, boost....and how you're reading it. Lots of so called fast IAT sensors...are not fast, so the lag will actually mean the temp can be worse.
And of course what you use it for. Simply running 1/8th mile will never be as risky as say a full mile.

And most typical IAT thermistors don't really read accurately above around 200degF either although you'd hope you're never up there.

Always strive for the coolest air you can. Too high is simply when detonation or engine health poses a problem from it and the tuning you are using for it.

But is hot air alone a problem ? No, sure people run no IC and get away with it. Just ensure anything is built/tuned around how it does run.

Mine is the stock IAT in the MAF. Should I get a stand alone IAT sensor and take it out of the intake pipe?

Originally Posted by dreksnot

Well, even on the street and a single 3rd gear pull, I hit high enough IATs to where I'd like to pull timing (see 3rd plot IAT Retard of -4.4*). This is without WI.

200* would worry me enough To do the WI setup too.

[stevieturbo]

Originally Posted by dreksnot

Well, even on the street and a single 3rd gear pull, I hit high enough IATs to where I'd like to pull timing (see 3rd plot IAT Retard of -4.4*). This is without WI.

Seems insanely hot 200degF ? Is this with no intercooler ? Or is it extremely hot ambients ?

Also, why so many differing boost readings ? You've one at 225kpa, 20psi and 32psi ?

[hillshooter]

Originally Posted by stevieturbo

The way it should be....that said, I had similar logs maybe 15+ years ago, but that was because the sensor I was using ( as supplied from ecu maker at the time ) was shit and woefully slow.
So intake temps never really rose, but it was only because the sensors was barely responding even by the end of a run when things were cooling down again lol.

This is just a GM sensor and a holley terminator. Same sensor I have always ran. I have checked it and it shows ambient when the car is cold. who knows though, I would like to verify it again.

[stevieturbo]

Originally Posted by hillshooter

This is just a GM sensor and a holley terminator. Same sensor I have always ran. I have checked it and it shows ambient when the car is cold. who knows though, I would like to verify it again.

Similar to what I use. Neither are super fast, but they are reasonable.

The really slow crappy one I used years ago was a totally different design, why Bosch even call it an air temp sensor is beyond me, although I guess it would probably have been ok for ambients.

A local Motec guy recently posted some testing of a sensor he uses, against the likes of what most would use ( ie yours and mine ) and his was actually impressively fast by comparison..

Although in my case, my charge temps are never much of a concern, so probably doesn't justify an expensive sensor.
If they were a lot hotter, I'd probably invest in one though