Optimum Intake Air Temperatures on Pump Fuel

[Audiomaker]

Hi Guys,

I've been wondering about intake temp's...

Could someone describe what would be good real-world intake temps, and also what would begin to be dangerous intake temps on 92oct pump fuel?

I understand this is boost related so would it be possible to include that?

For example:

200 degrees @ 6-8lbs = happy?

200 degrees @ 10-14lbs = Not Happy?

100 degrees @ 10-14lbs = Happy?


I'm making these numbers up.... I'm trying to get an understanding of what the temperature limits are per/boost on pump fuel, and also what an intercooler needs to accomplish in temperature reduction to allow for increased boost?

Also, any idea on average turbo air exit temp's @ boost vs ambient?

Just trying to get some real world numbers.

Thanks
Sean

 

[E Zurcher]

Not a pro here but i don't thing the intake temps matter with a turbo. Of course the lower the better but your wastegate is going to blow off at it's set pressure no matter what.

 

[Audiomaker]

Not a pro here but i don't thing the intake temps matter with a turbo. Of course the lower the better but your wastegate is going to blow off at it's set pressure no matter what.

I'm pretty sure they do. Some air temps, combined with some pressures, combined with octane rating of fuel will cause detonation.

If I wasn't specific, I'm talking about intake at the manifold, not at the air filter... post turbo and intercooler (if you have one).... on 92oct (really should be 87oct since you can't trust pump fuel to be more than this).

 

[Boosted Cycle Perf]

Not a pro here but i don't thing the intake temps matter with a turbo. Of course the lower the better but your wastegate is going to blow off at it's set pressure no matter what.

First off, the wastegate doesn't blow off anything. The blow off valve blows off to release boost pressure to reduce/eliminate compressor surge, or back spin.

The wastegate, which is attached to the exhaust before the turbo is what regulates how much boost the turbo makes.

Now. IATs is everything when it comes to boost. Anytime air is compressed it creates heat. But how much heat is the soften e between you motor living to see another day, or it melting pistons.

I don't remeber exact numbers, but for some reason I recal no intercooled bikes getting well over 200 degrees, while the new ultra plenums knock them down to less then 160. But don't quote me for sure.

 

[Audiomaker]

First off, the wastegate doesn't blow off anything. The blow off valve blows off to release boost pressure to reduce/eliminate compressor surge, or back spin.

The wastegate, which is attached to the exhaust before the turbo is what regulates how much boost the turbo makes.

Now. IATs is everything when it comes to boost. Anytime air is compressed it creates heat. But how much heat is the soften e between you motor living to see another day, or it melting pistons.

I don't remeber exact numbers, but for some reason I recal no intercooled bikes getting well over 200 degrees, while the new ultra plenums knock them down to less then 160. But don't quote me for sure.

Yeah, I didn't think the answer was going to be so elusive when I asked it. I mean some of the car guys are monitoring their IAT's, but I was looking for specific T-Busa information on what are acceptable formulas.

Murdered, you have a high horsepower Turbo running on pump right?

What is it like? Just like install the intercooler kit and turn the boost up to what it says on the box without any verification or knowing what the actual IAT's are....all just blind faith?

If you're running 93, what if you get some bad gas? Without some sort of reference, do you know if say...90oct is within the safety margin for your motor using that intercooler?

If one knew what IAT's were OK at what PSI, at what octane, one might discover that they are boosting close to the limit, or maybe could choose to boost a little less, or possibly could upgrade their intercooler...etc...etc.?

Otherwise it's this mystery information, a lot of trust, and a lot of praying.


Sean

 

[Boosted Cycle Perf]

High hp...I wouldn't say that. I do have a stage 2 Rcc turbo with an ultra plenum. I run pump gas only. I also tune my personal bike leaner then what most people deem "safe". (11.8) I tune my bike to 12.2-3afr. Right now I'm at redline I touch 15psi. I had it on the dyno at 12 and it made 317hp. So I figure now it's at least 330-340hp. Will it melt a piston if I get some bad fuel? Perhaps. Not really worried about it. But would I tune a costumers bike that lean? No. At 11.8 there's plenty of safety if you get some bad fuel.

In the last 12 years turbo busas have pretty much gotten down to a science. And a good part of that has been perfected by Rcc. I'm a dealer for Rcc, and when richard says its gonna make 250hp it does. When he says it will make 280hp it does. When he says it will make 600hp it does. When he says ultras will make 380 on pump gas, I don't sweat it. Point being is there's enough experience around that I've acquired that I don't worry about iat's. I just know the thresholds of when race fuel, meth injection, air to air, or ultra plenums need to be used.

Hope that kinda answers your question?

 

[Audiomaker]

High hp...I wouldn't say that. I do have a stage 2 Rcc turbo with an ultra plenum. I run pump gas only. I also tune my personal bike leaner then what most people deem "safe". (11.8) I tune my bike to 12.2-3afr. Right now I'm at redline I touch 15psi. I had it on the dyno at 12 and it made 317hp. So I figure now it's at least 330-340hp. Will it melt a piston if I get some bad fuel? Perhaps. Not really worried about it. But would I tune a costumers bike that lean? No. At 11.8 there's plenty of safety if you get some bad fuel.

In the last 12 years turbo busas have pretty much gotten down to a science. And a good part of that has been perfected by Rcc. I'm a dealer for Rcc, and when richard says its gonna make 250hp it does. When he says it will make 280hp it does. When he says it will make 600hp it does. When he says ultras will make 380 on pump gas, I don't sweat it. Point being is there's enough experience around that I've acquired that I don't worry about iat's. I just know the thresholds of when race fuel, meth injection, air to air, or ultra plenums need to be used.

Hope that kinda answers your question?

Well, it does answer the question that most installers and tuners are probably going with whatever numbers the intercooler manufacturer presents, and I get that... it makes sense.

I think however that we would agree that if I put 93oct in my non-intercooled bike and put 12lbs to it, that I wouldn't go very far no matter what AFR I attempted to achieve.

At 93oct and 7psi, I can ride from Houston to Oregon in 106* heat....which you know I have.

That 5lbs of boost difference being acceptable is the difference in IAT.... obvious.

Maybe I'm OCD'ing on this, but it seems odd to me that these temps aren't common knowledge.

I'm sure there's a graph or chart on the net somewhere (I've been looking), but I figured wrongly that the answer would be readily known and available.

I will find out however... even if it's just so it stops bothering me and nothing more.


Sean

 

[2wicked]

One thing that might make this more interesting for you is that x amount of boost does not create y amount of heat, different turbos with different flow rates will show different IATs, also the longer you boost the hotter your charge air will get. So looking for specific #s is never going to happen for you, 12 psi of boost, non intercooled may make 160 F, but stay WOT for a few seconds and that temp can rise to over 200 F, stay in it longer and the temps go higher. So if you are looking for a simple answer you will not find one, there are many variables,

Richard