Intake tube and heat soak

[mike the snake]

One thing I've noticed on my turboed BRZ, is the metal intake tube heat soaks, and basically gets as hot as the engine bay.

I'm not sure how much this affects IAT's, as the air only spends a split second flowing through that hot intake tube.

I was thinking about insulating the intake tube, or applying that gold heat shielding, but eventually the intake tube will still become heat soaked.

SO, what if, one were to install an insulated tube around the intake tube, and connect a small fan and tube that draws air from in front of the radiator?

It would be relatively easy to make and would have atmosphere temp air flowing over the intake tube. A small, low-draw electric fan could be employed.

It seems like something that's easy and inexpensive enough to try.

The one thing I don't know is, would this be worth doing? Would keeping the intake tube cooler really help things that much?

I would think anything one can do to lower IAT's will help, and it might make the tune more consistent at various temperatures?

[Boss Paco]

Hopefully your intake is aluminum cos it will shed heat quickly. My IATs climb when still and quickly drop when I drive. Usually 10ish over ambient when in motion and I've seen upwards of 50 over when still for extended periods.

I have a SBD turbo kit, just so you know.

[mike the snake]

I think the IAT's you are seeing change because the speed of the air through the hot intake tube. The air at idle is collecting heat as it slowly moves through the hot tube, and when moving, the air zips through the hot tube fast enough to not collect as much heat.

I felt my intake tube immediately after driving, stopping, and immediately opening the hood, and the tube was very hot.

The plastic intake manifold is cool, but the aluminum intake tube just seems to run at whatever the engine bay temps are at.

Installing a tube, maybe 1/2" larger in diameter around the intake tube, with a small fan blowing cold air around it I think would effectively keep the intake tube a lot cooler. The tube would act as an insulator, and a small inline fan blowing cool air would help evacuate any hot air radiating in from the engine bay.

Once the aluminum intake tube gets hot, it's not going to cool back off.

If the intake tube has cold air from in front of the radiator flowing over it all the time, it might never get hot, which might be good for a few degrees cooler IAT's, maybe?

[SilverSkyline210]

first, i'd like you to watch this, interesting watch
[ame="https://www.youtube.com/watch?v=vqDbMEdLiCs"]Misconceptions About Temperature - YouTube[/ame]

and i also have a FBM turbo kit and when i first put it on completely unwrapped, i use to have issues driving away from a light after it would heat soak, because because the MAF is right on that bottom side of that pipe, but after i wrapped it with DEI gold reflective tape, i have to say that never happens anymore, because it reflects all radiation so it does a real good job of keeping it cool, im still running a stock hood too btw, sometimes simplicity is best

[mike the snake]

Ideally, the intake tube would be made of plastic, just like the intake manifold.

I still think that keeping the aluminum intake tube from getting hot in the first place might be good for some gains.

[King Tut]

Seems simple to me. Purchase the gold foil, do some datalogs, install gold foil, repeat datalogs, and finally post results here. I was eventually planning on wrapping my intake pipe just like @SilverSkyline210.

[mike the snake]

I'm going to start with the gold foil.

[xwd]

Yeah the gold foil is very good at reflecting radiant heat. I used it extensively in my WRX with a FMIC has a similar layout with the piping although it enters in the rear. I had a Davtron 2-probe temp gauge installed pre/post IC and along with the IAT I could measure temps pretty well. You can also simply use an infrared pyrometer to measure the temp on the outside. The gold foil really did help in keeping all of the piping cooler.

Another +1 for gold foil is I have remote reservoirs for my suspension mounted to the Grimmspeed strut bar, right above the engine... They are black anodized aluminum and were getting way too hot and actually increasing pressure 3-4psi in each canister. Adding the gold tape dropped the surface temp of them by like 30-40 degrees and I no longer see much of a pressure increase.

I do plan on getting a vented hood for the car when going FI.

[yomny]

I may end up doing the temp logging.. just a bit less detailed.. when i drive home from work i usually let the car cool down a bit while i check under the hood to make sure everything is still good (recently installed FI kit). Yesterday i decided to touch the cold pipe before the TB and damn it was hot.. I'll take the temp today with an IR gun and then once after the wrapping(different day after another drive from work). I know this isn't a science experiment and may not be 100% accurate but it'll provide some data. Anything that reflects the heat has to help to some degree maybe not to justify the cost of that gold tape though.

[mrk1]

I've logged my IAT's and they are only a touch over ambient during pulls, thats also with my filter in the engine bay too. More often I have done the old fashion hand test, touch the upper pipe after going for a rip. Its warm but never what I would call hot. You are exactly correct, the air moves pretty quickly through the pipe so it doesn't have much time to absorb heat. You can see in the pic I have an aluminum heat shield on my upper pipe, this provides an air gap between the shield and pipe. The gold foil and turbo blanket also helps a ton. Also after this photo I have added a shroud to my intercooler so that will help out its efficiency. And to answer you comment about IAT's and tunes, if your MAF is located in the upper IC pipe it should have no problem reading any temperature fluctuations and making adjustments, this is one of the benefits of a blow through MAF.

[yomny]

Originally Posted by mrk1

I've logged my IAT's and they are only a touch over ambient during pulls, thats also with my filter in the engine bay too. More often I have done the old fashion hand test, touch the upper pipe after going for a rip. Its warm but never what I would call hot. You are exactly correct, the air moves pretty quickly through the pipe so it doesn't have much time to absorb heat. You can see in the pic I have an aluminum heat shield on my upper pipe, this provides an air gap between the shield and pipe. The gold foil and turbo blanket also helps a ton. Also after this photo I have added a shroud to my intercooler so that will help out its efficiency. And to answer you comment about IAT's and tunes, if your MAF is located in the upper IC pipe it should have no problem reading any temperature fluctuations and making adjustments, this is one of the benefits of a blow through MAF.

Damn that looks like something out of a magazine.. and it looks like you cooler lines go to the ABS lol. That sir is clean.. which i had the abilities to create my own brackets/shields.. clean looking oil cooler mount.

[mrk1]

Thanks, the oil cooler lines are capped and just pushed off to the side in that photo. I was having some leak issues at the sandwich plate.

Duct work,

[CSG Mike]

Originally Posted by mrk1

I've logged my IAT's and they are only a touch over ambient during pulls, thats also with my filter in the engine bay too. More often I have done the old fashion hand test, touch the upper pipe after going for a rip. Its warm but never what I would call hot. You are exactly correct, the air moves pretty quickly through the pipe so it doesn't have much time to absorb heat. You can see in the pic I have an aluminum heat shield on my upper pipe, this provides an air gap between the shield and pipe. The gold foil and turbo blanket also helps a ton. Also after this photo I have added a shroud to my intercooler so that will help out its efficiency. And to answer you comment about IAT's and tunes, if your MAF is located in the upper IC pipe it should have no problem reading any temperature fluctuations and making adjustments, this is one of the benefits of a blow through MAF.

To add onto this, the airflow in the intake tube is only there for a moment, but the total mass of air going through the intake tube is pretty substantial compared to the amount of space there.

Even if the intake charge temp goes up 1F from soaking from the intake tube, the tube itself is being cooled by the intake charge absorbing that heat, and the tube will cool down quickly.

Your observations are dead on!

[yomny]

Originally Posted by mrk1

Thanks, the oil cooler lines are capped and just pushed off to the side in that photo. I was having some leak issues at the sandwich plate.

Duct work,

Yeah.... i just went through your build thread.. can't really type anything that could express what i feel, its that good. Question if you dont mind.. the gold shield on your charge pipe, how's it mounted, got a bolt on the opposite side? had parts puts together to make my own oil cooler since my JDL setup doesn't have much room for the typical coolers out there but i need to mount.. my prefer location is where you have it again as my intercooler wont allow me to use the front. How or where did you mount yours. I'll see if i could make something to hold it in that area. Thanks