[leftcoastman]

This is my first turbo vehicle, so I'm new to monitoring intake air temps. What are acceptable/preferable intake air temperature values?

I've been doing a lot of logging lately and on my 40-150mph pulls, I can get those IATs to over 200 degrees! That can't be good.

[ironic]

This is good info to have; also what should we be looking for as far as AFRs go? Are there any other parameters the more experienced guys could share that we should wathc out for. Sorry for the noobie questions but I'm trying to learn =]

[Former_Boosted_IS]

Originally Posted by leftcoastman

This is my first turbo vehicle, so I'm new to monitoring intake air temps. What are acceptable/preferable intake air temperature values?

I've been doing a lot of logging lately and on my 40-150mph pulls, I can get those IATs to over 200 degrees! That can't be good.

Can you give more info? Tune? Boost? DPs?

[leftcoastman]

I'd rather not, so as not to start a tuning/DP war. It was a question on IATs, not my specific car. Thanks for any help you can provide.

[Former_Boosted_IS]

Originally Posted by leftcoastman

I'd rather not, so as not to start a tuning/DP war. It was a question on IATs, not my specific car. Thanks for any help you can provide.

I am sure you understand the importance here though. Boost levels and their relation to IAT's has long been questioned. This can help us to know whether we are out of the efficiency range of the turbos. Catless DPs should help alleviate some heat as well, so it would be good to know if you were catless. Intake info as well could be insightful. If you don't want to post it up here, I would love to hear via pm?

[e90AW335i]

What kind of Intake, What kind of Intercooler, Are you catless, etc....

We need more information to understand the conditions.....

[JOe335i]

you wont start a tuner war, at least tell us the PSI, what octane, and if you have DP, u dont have to name any brands, its hard to help without knowing the full story.

[EastCoast335i]

Originally Posted by JOe335i

you wont start a tuner war, at least tell us the PSI, what octane, and if you have DP, u dont have to name any brands, its hard to help without knowing the full story.

+1 some details please

[leftcoastman]

Well I will divulge detail because it looks like that's what you guys want for your own purposes, which is fair enough.

My simple question was: What is a normally acceptable IAT? Not sure how that depends on boost/dp/intake/etc. It's a simple question, isn't it? Unless having a DP allows you to run higher IAT, which would surprise me.

That said, this is all encountered on the track during 20-30 minute hot lap sessions. I do not encounter anything near this on the street as it's virtually impossible to work the car that hard on the street.

Octane doesn't matter. I ran 91, I ran 95, I ran 98, I've run 100 - all result in the same IAT spiking. IC is stock. High flow cats, but stock everything else. I'm running roughly 12psi.

In say, 85 degree ambients, the IAT will start the "pull" at 120 degrees or so and spike to 200+ by 150mph. Within about 5 seconds (the sweeper turn where I'm not on full boost), the IAT will drop back to 140 or so. The short straight between turn 1 and 2 will spike it back up to 160...and so on.

[OpenFlash]

Yep... those temps are expected during sustained lapping conditions. This is why it is important to run race gas or a race gas mixture during these racing conditions. While the PROcede does drop boost and pull back timing during these conditions, the extra octane does help combat knock activity that would otherwise be caused by excessive air charge temp.

FWIW, I'd guess that turbo outlet temps (pre-Intercooler) are around 300F during these conditions.

Shiv

[leftcoastman]

Shiv - would an aftermarket IC make an appreciable difference? All the data I've seen are related to single dyno pulls.

As you know, 30 minutes of hot lapping makes a dyno pull seem like a walk in the park.

[OpenFlash]

Originally Posted by leftcoastman

Shiv - would an aftermarket IC make an appreciable difference? All the data I've seen are related to single dyno pulls.

As you know, 30 minutes of hot lapping makes a dyno pull seem like a walk in the park.

A good intercooler will make a difference for sure. It may take longer to cool down once hot (due to having more thermal mass) but max temps could be 40-60F lower. Depending on the core design, it may have either positive or negative effects on radiator efficiency.

Shiv