insulated intercooler-to-intake pipes

[supernova_6969]

Hi guys. 

 

as some of you guys might have seen from another topic I started (http://forums.hybridz.org/topic/122459-air-intake-temperature-soar-when-i-step-off-the-gas/), I've been giving some thoughts to the air intake temperature. 

 

Afer poking around the engine while it was still warm, I realized that all the metal air pipes (duh, yeah i know, but it's important for heat conduction) were exposed to the warm engine bay air, and to the engine's radiating heat, and that the radiator's fan blew hot air pretty much directly on them.  Touching all these nice pipes, I realized that the pipe from the turbo to the intercooler pretty much too hot to touch (duh again, I'd read about the heat coming from compressing the air but you don't realize how hot till you experience it).  

 

I also realized that the pipe from the intercooler to the throttle body started off cool and ended up very warm (can touch for a few seconds) close to the TB.  The transition was quite sharp where I've placed a heat shield (sheet metal cut to fit around the pipes to try to limit the filter breathing in air from the engine bay - it didn't make much of a difference for the air temp there).  I don't know if the heat shield is helping or it's just because the hot air blown by the fan hits the pipe from there on...  

 

I started looking around on the net, and some people had also thought of insulating this particular pipe.  There is some debate as to the usefulness of doing this, and none of the sites were particularly methodical  with the data taking, so i figured I'd try it, and gather before and after data too.  

 

Here is a series of pictures as to what I did to insulate the pipe (after gathering data;  more on this later)

 

this is the piping system, as I got the car (plus the heat shield I made)

 

This is the insulation I've used.  It's a foam tube to insulate house piping bought at a hardware store for 5$ for 6 feet, 2inch diameter.  as you can see, I cut triangles out so I'd be able to bend it to follow the pipe.  I eyeballed the cuts, and had to make the triangles wider only once to be able to follow the curve of the pipe

 

this is the other side, since the pipe is s-shaped. 

 

with the foam almost all on the pipe to illustrate the use of the cuts

 

With it all in place.

 

tie wrapped on, ghetto style with ugly, white, break-if-you-look-at-them-too-long tie-wraps I had around

 

The final product, with the heat shield seen from a different angle.  I know there are gaps in the insulation, but i figure this can be a prototype and i can make it better if it turns out to be useful....

 

I'll try to post tomorrow on the data I've gathered about the intake temperature before the insulation mod; the file is on my work computer.  I've gathered a bunch of info on how fast the temperature goes up once I'm parked iddling after the drive to work.  I've got graphs and all, easy to read.  post insulation data will be another week or so, I'm guessing, since I don't drive it to work every day (t-tops were leaky, and I've recently cut out part of the floor to fix rust, so no driving when it's wet)

 

I'm also planning on changing the air filter location and making a cold air scoop under the radiator mount, so that and other data will be useful on that too.  Stay tuned for other topics I'll start when I gather the supplies I need, the main supply I lack being time)...

 

Comments and suggestions welcomed, follow this post if you're curious to see how it turned out.  

 

 

******************************see posts 2 and 5 for info, and post 15 for a pre-emptive conclusion********************************

Edited June 26, 2015 by supernova_6969

[supernova_6969]

so here is the baseline data

this is esentially the temperature at the filter (dark blue) and in the intake manifold (pale blue) at iddle, once I get to the parking lot at my work. 

This entails driving on the highway for at least 10 minutes (meaning everything is fresh and cool in the engine and engine bay), then going stop and go city driving for about 2 minutes, then parking. 

 

 

What I get from this is that as I park, the filter is still sucking in pretty cool air, but then warms up rather quickly (from 28 Celsius/82 Fahrenheit to 63C/145F in about 4 minutes).  on the other hand, the manifold air temp goes up much much slower, but still goes up a little (from 70 Celsius/158 Fahrenheit to 80C/176Fin about 4 minutes).  

 

If my contraption is effective, I expect that the air temp at the filter will climb just as fast and as much, but that the air temp in the manifold will be slower to climb.

 

I'ts been rainy over here, so i haven't had much of a chance to drive her in the last week, but as soon as I do two consecutive days, i'll post the new tables with this data and also the new data for a direct comparison.

Edited June 28, 2015 by supernova_6969

[supernova_6969]

****sorry guys, i keep forgettingto post the data.   tomorow, I'm putting on an alarm!!!!

[supernova_6969]

Baseline data in post number 2!

 

Actual post-mod data as soon as I can gather it!

[supernova_6969]

hi!

 

I ran the car today with the insulation for the first time and the preliminary data suggests that it might actually make a difference (not sure if it's a big wnough difference for it to be worthy).  I don't want to post a graph just yet, not until i've got at least 2-3 runs on it, to get an average... 

 

One thing I CAN tell for certain is that the pipe from the intercooler to the intake is SIGNIFICANTLY cooler. 

 

I'm talking from too-hot-to-touch-for-more-than-2-seconds to cool-to-the-touch.  And that's after iddling for 4 minutes with surrounding engine bay air temperatures of about 122 Farenheight (50C).

 

So I can conclude that the pipe itself is at least 45F (25celsius) COOLER with the insulation.  Whether that has an effect on intake temperatures, I'm not certain.  Stay posted.

 

oh!

 

I see that a few people have viewed this, but no one has left comments;  I get that since it's all baseline and shit so far, it doesn't really creates the space for a discussion, but I don't want to post stuff that is uninteresting at large, so if you ARE interested, or curious, please let me know... just say hi or something. 

Edited June 28, 2015 by supernova_6969

[TimZ]

hi!

 

I ran the car today with the insulation for the first time and the preliminary data suggests that it might actually make a difference (not sure if it's a big wnough difference for it to be worthy).  I don't want to post a graph just yet, not until i've got at least 2-3 runs on it, to get an average... 

 

One thing I CAN tell for certain is that the pipe from the intercooler to the intake is SIGNIFICANTLY cooler. 

 

I'm talking from too-hot-to-touch-for-more-than-2-seconds to cool-to-the-touch.  And that's after iddling for 4 minutes with surrounding engine bay air temperatures of about 122 Farenheight (50C).

 

So I can conclude that the pipe itself is at least 45F (25celsius) COOLER with the insulation.  Whether that has an effect on intake temperatures, I'm not certain.  Stay posted.

 

oh!

 

I see that a few people have viewed this, but no one has left comments;  I get that since it's all baseline and shit so far, it doesn't really creates the space for a discussion, but I don't want to post stuff that is uninteresting at large, so if you ARE interested, or curious, please let me know... just say hi or something. 

Hi.

 

My take on this is that it's "directionally correct", but I'm not sure how much heat that pipe can end up transmitting to the intake air, since it moves by it pretty fast.  I guess to say it more accurately, I doubt that the amount of heat that you end up transferring away from the pipe is enough to significantly raise the temperature of the large amount of air passing through it.  It _will_ probably help quite a bit with heat soak before warm starts, though.

 

That said, it _is_ directionally correct - every little bit helps, and it's not like you spent a lot of money on it.  You could even pretty it up by wrapping it in some nice heat reflective tape!

 

Also, this mod will probably not be directionally correct on the turbo-to-intercooler pipe, since it is likely hotter than the engine bay air.

[supernova_6969]

Thanks tim
Yeah im thinking the same. Under actual driving it probably wont change anything.

Im also taking data when i'm actually driving but i dont have enough to conclude anything yet.

As for the other pipes, yeah the turbo to intercooler is actually warmer than the sutrounding air, so that would be a bad place to insulate. I was giving some thoughts on insulating the filter to turbo though... I'll see it that'ds worth it once i finish this bunch of tests.  one mod at a time to be able to see each's impact.

Thanks for the reply.

oh!

 

as an afterthought regarding air speed, you chan check this thread http://forums.hybridz.org/topic/122459-air-intake-temperature-soar-when-i-step-off-the-gas/ where I discuss air temp spikes under certain conditions.  that's how I started looking into reducing the spike;  it takes place at a time where the air is going significantly slower..  but again, not certain how much of an impact it can have. hopefully a clear answer will come up.

Edited June 11, 2015 by supernova_6969

[redzedturbo]

Im about to get extensive on shielding all hot parts but i have seen people in the rice world use header wrap on all charge pipes and say it works wonders but not much in the proof dept. best of luck. i will post my results when i do mine!!

[supernova_6969]

Red zed, are you going to dyno before and after? Or measure temps in the engine bay?

 

From what ive read wrapping the exhaust manifold is supposed to help keep the heat of the gases and thus the more exhaust gas pressures. Not certain how much pressure you can loose in less than a foot of piping but..... Would love to find out if it actually does anything significant.

 

You can also measure the engine bay temps and see how long it takes to reach a certain temp once you stop driving before and after wrapping.... That would tell us if it does anything for temps...

Edited June 12, 2015 by supernova_6969

[redzedturbo]

I think im going to base mine on underhood temp and air intake temp. I do have a lazer temp gun that works well as well as megasquirt sensors it should be good.

[Wedge]

Interesting.

[FricFrac]

Interesting for sure. The things we do know make a difference I'm not sure if you've done yet - wrapping the manifold, turbo blanket a at least the down pipe makes a significant difference first for performance and secondly for keeping temps 8n the engine bay down. Secondly ducting to your intercooler will have a significant effect on its efficiency

[supernova_6969]

Hey fric. I read about wrapping the exhaust.. Although ive never seen data about before and after re: performance. The actual engine bay temps dont bother me all that much ( unless like in my case the intake is in the bay i guess) but its definately interesting...

 

What do you mean by ducting the intercooler?

***edit: i just realised what you mean. Ducting it is an idea i've been really excited about... Its simple and easy and i suspect the results will be good. Im currently waiting for the next political campain yo gather a bunch of coroplast to usr as a mock up, as it sturdier than cardboard.....

Edited June 21, 2015 by supernova_6969

[supernova_6969]

Hi guys I know its been a while and it seems like I'm not doing anything with the car. Don't worry about it... I've tried to gather data but everything didn't work out as I planned. First my car started to untune itself (megasquirt), then i tried to gather data but the laptop battery died on me as i was parking, ready ti reccord.. Finally I did manage to get 2 or 3 iddling's worth of data but then the problem was that it was inconclusive so I'm going to try to get another day's worth it and posted as soon as I can.

Thanks for being here...

[supernova_6969]

ok!

 

So I got more data (3-4 more runs) and the averages stay pretty stable.  Remember I parked the car, and kept it iddling for 3 minutes while gathering info on the time, the ouside temp, the filter temp and the intake manifold air temp (MAT).  Here are the graphs that I thought would be important (graphs have a lot of info in the titles, including some of my conclusions:

 

The difference between the filter temps and the MAT  (the blue line are before insulation, red after):

 

 

and the overall temps at the filter and from the MAT (the blue lines are before insulation, red after)

 

 

 

Overall, at this point in time, my conclusions on simply insulating the pipe that goes from the intercooler to the throttle body are as follow:

1- the temperature of the pipe that is now insulated has DROPPED significantly. that is the pipe's temperature only (see post #5)...

2- this seems to make the temperature of the the air in the intake manifold get warm SLIGHTLY slower . probably not significantly so. this could be useful for when you're at a light or getting ready for a drag.

3- the overall temps of the air in the intake manif. seems to be very SLIGHTLY lower on average.  probably not significantly so...  Meaning that insulating the pipe might not be really worth it... 

 

My thoughts at this point? 

1-maybe i should move the MAT sensor to the piping just in front of the throttle body;  I have a strong suspicion that the intake manifold radiates heat that influences the MAT data (http://forums.hybridz.org/topic/122459-air-intake-temperature-soar-when-i-step-off-the-gas/)

2- no matter what, the air around the filter gets stupidly hot when iddling, so I need to pick up some colder air. which means I'm about to start construcing a cold air kit.  stay tuned, i'll post about it and then link it here.

 

PLEASE comment!

 

[supernova_6969]

hi!

 

resurrecting here, but I have some new, significant info about this.

 

I did end up moving my IAT sensor to the pipe that I insulated, over from the manifold.  measured temperatures when from anywhere between 100f and 200F, with wild, rapid ups and downs based on throttle (closed throttle = hot open throttle/boost, cold).

 

since I've moved it, anytime the car is moving the recorded temps are about 10-20 above ambient (these days 65-70), and they haven't gotten past 102 (in heavy traffic).  And there is no wild see-saw based on throttle, it's just a very stable reading that only slowly increases when the engine bay increases.. 

 

I've checked the pipe temperature (with my hand) after a drive, with and without the wrapping, and if it's not insulated, the pipe is warm-ish.  insulated, it's actually cool...  so the insulation makes a difference in the pipe temp.  does that translate to air temp?  I'm doubtful. 

 

HOWEVER!  I've realised that the insulation could actually increase the hot start heat soaking issue;  an hour or so after the engine is shut off, the pipe is actually mildly warm while everything else is mostly cool (not the engine, but the surrounding metal).  so, yeah..... I think it could help with very short term hot start (say, you shut the engine off and start it again withing 10-20 mins), but anything longer than that and there might be a slight downside..... IF it actually does anything.

 

I'm still considering doing something in the same family of a cold air intake, but have changed my mind about how I would do this (I originally thought of moving the filter down low where it could breather the cold air from under the car, with or without some kind of splash guard)...  My new Idea is to drill holes in the sheet metal under the air filter (the very front part of the wheel well, between the light and the stock coil location) and building an air box that will only allow the filter to breathe from there and not from the hot engine bay.  that should make certain that the engine breathes cold air no matter what the engine bay temps.  and yes, i'lll do something to prevent water coming from the wheel to splash up, right into the intake...    I guess I'll try and then post about it. 

Edited September 23, 2016 by supernova_6969

[redzedturbo]

The hot start problem we all face has lots less to do with incoming air temp and more to do with heat soak in the fuel rail and injectors or carbs which ever you may have. The fuel gets hot enough it looses its liquid state and turns to a gaseous state. If you have hot start problems your best time spent is header wrap or some kind of thermal layer between the header and intake or wrapping the fuel rail with some GOOD thermal reflecting Martial. I made an abs panel from a semi mud flap at work to block air from entering my air dam and going under the radiator because it was open before and now its hard to keep the car at 180 deg if moving at all. This was a good cooling mod on the cheap. Will take a pic tomorrow and post it.