Keeping the heat out

[2013MustangGT]

I found this and thought if it works this would be great mod for my Mustang that I track. What do you think?


Heatshield Products Coyote Intake Manifold Heatshield

"In testing, Hestshield Products customer Paul’s Automotive saw a 12 hp increase on the Mustang they tested this intake shield with. The intake shield was the only modification performed for this test."

http://www.stangtv.com/project-cars...d-products-coyote-intake-manifold-heatshield/

 

[csamsh]

Had nothing to do with pulling to higher rpm's I guess...I think snake oil.

If it's super cheap, what the hell? Go for it.

 

[SoundGuyDave]

Also, just to show you that dyno numbers aren't always all that, take a look at around 2300RPM, and you'll see that the heat shield apparently COST horsepower... The composite manifolds we run are really pretty good at rejecting heat to begin with, so I think the main gains you'll get will be from wallet-based weight reduction.

 

[Sky Render]

That might be a nice piece if the Coyote's manifold was made out of metal, but plastic doesn't really transmit heat well. Maybe if you're hot lapping flat-out in like 100+ degree temps it would help.

 

[Full_Tilt]

12 hp increase http://www.stangtv.com/project-cars...d-products-coyote-intake-manifold-heatshield/

lol

 

[frank s]

I have no idea how you'd determine which of all the influences resulted in a HP increase; surely theory would suggest reducing temperature of the incoming charge would contribute, as would a desire to sell an injudicious order of heat-shield material.

When I was trying to go faster without spending much money I eagerly sought simple, cheap remedies for the lack of power. One such was said to be lowering underhood temperatures. An attractive simple-cheap was to paint everything in there flat black; it would absorb heat more readily, and the other side of the metal (hood surface, fender wells, firewall, etc.) would radiate heat to the outside airstream. Well, maybe so. But could you believe the tiny increments that measurements would likely reveal? All within testing-error, I'd guess. Plus which, it's much, much more difficult to work with mechanical pieces containing hot fluids in such a dark environment. I'd be interested in seeing any actual data with regard to true gains. Too much of what we read are merely "(Wouldn't it be nice if) flat black underhood cools the engine and helps it generate more power" wishful thinkings.

Remember, we are admonished:

"In this universe there are things
that just don't yield to thinking
—plain or fancy— Dude".
—J. Spicoli, PolyPartyPerson

 

[2013MustangGT]

That's what I thought.

 

[fdjizm]

My testing in 2010.
http://www.s197forum.com/forum/showthread.php?t=45958

the pics are probably not hosted anymore but I put some sticky sided aluminum insulation under the bare plastic on the intake manifold. I felt it would make a difference as the valley in the engine is pretty much just baking the underside of your intake while your're chilling in the staging lanes.

I was right

****SCIENTIFIC TESTING****
Gentlemen, I set out to test my theory and the results are in.
All tests in the following format.
Cold start, drive 15 min to work, come back shut off car, let sit for 10 min, take temp. Mini infrared temp sensor used.

Test 1 stock intake no insulation...
Outside temp: 45.3 F
Empty area under intake: 168.9 F
Valve cover: 175.4
Actual Plastic rear underside of intake: 110.2 F

Test 2 1/2 hours later installed CMCV delete plates added insulation.
Outside temp: 44.7 F
Empty area under intake: 167.5 F
Valve cover: 175.1
Actual Plastic rear underside of intake: 100.6 F

Just a note, there are no HP gains from doing this beyond keeping the intake just a tad cooler while sitting. (or buying time before getting heatsoaked.)
IMO it's good for sitting in the staging lanes waiting for everyone to move before you get to race and not being heatsoaked to death.

 

[SoundGuyDave]

What's a staging lane?


Sorry, I just had to... For the corner-carving application, where a "run" is going to be somewhere between fifteen minutes (NASA TT session) and 25 hours (Thunderhill enduro), the intake is GOING to normalize to temp. Granted, the insulation MAY cause the intake surface temps to take longer before reaching equilibrium, but they'll get there just the same. Once they're there, they'll stay there until the car cools off, in the paddock, between sessions. This is the main reason why you don't see a lot of forced-induction road racers. FANTASTIC fun for the first 10 minutes or so, but then they just fall on their faces when the intercooler gets heat-soaked, and the ECU pulls timing to keep the motor alive.

Just sayin'...

 

[JAJ]

The issue of heat-soak in the naturally aspirated Coyote is really only a factor when you're not working the engine hard.

At full throttle and 6000+ RPM, the Coyote swallows nearly 40 pounds of air every minute. The manifold holds a little less than 1/2 ounce. The air in the manifold changes completely more than 1000 times every minute, or about 20 times a second. It's just not in there long enough to get warm even if the manifold is warm, and more to the point, it sucks all the heat out of the manifold very quickly and the intake air is pretty much at the same temperature as ambient.

 

[SoundGuyDave]

JAJ, can you confirm your dimensional measurements? 1oz is roughly 29.5cc, and I'm pretty sure that the plenum area behind the throttle body is considerably larger than that. Im also nearly positive that each of the intake ports in the head are also larger (much!) than 29.5cc by themselves. I just can't see pouring in a half-shot-glass of water and seeing the manifold fill up.

That said, the main thrust of your argument is correct. The intake air charge will help cool the intake plenum, as will the airflow between the valley in the block and the bottom of the intake plenum, which you will see at speed on track, but not on the dyno.

The crux of this argument is really about the difference between drag racing and road racing... In drag racing, you spend an inordinate amount of time sitting around in the staging lanes, either idling, or starting, moving, stopping, repeating. All that does tend to increase intake manifold heat simply from the ambient temprature of the block and heads, as there is no airflow (internal or external) to help cool it off. In road racing, though, even if you pull out of the pits with a cold engine, by the time the warmup/parade lap is complete, and the green flag flies, the engine is warmed up, but the manifold isn't. Why? Airflow, both internal and external, as you mentioned.

For drag racing purposes, the insulation sheet being discussed MIGHT be worth SOMETHING, but for road racing? Nada.

 

[zeroescape]

I think you guys are mixing up heat soak and heat transfer. Thats like saying im just as hot in the shade vs in the sun even though the air temp is the same, but we all know the heat transfer is much greater in direct sun light due to radiant heat.


I cannot vouch for quality or how much heat it can reflect but the idea is not simple insulation like in your house.

 

[JAJ]

JAJ, can you confirm your dimensional measurements? 1oz is roughly 29.5cc, and I'm pretty sure that the plenum area behind the throttle body is considerably larger than that. Im also nearly positive that each of the intake ports in the head are also larger (much!) than 29.5cc by themselves. I just can't see pouring in a half-shot-glass of water and seeing the manifold fill up.

Whoever decided to use "ounces" for both weight and volume measurements created the opportunity for confusion.

The Coyote intake manifold volume is 11 liters and air has a density of 1.2 grams per liter. The manifold holds 11 liters x 1.2 grams/liter = 13.2 grams of air, or 0.47 ounces.

The Mass Air Flow sensor reads air mass (not volume) in pounds per minute, and from datalogging I know that the max MAF reading with a stock Coyote is about 40 pounds per minute, which is 640 ounces per minute. 640 ounces divided by 0.47 ounces is about 1300 air changes in the manifold every minute, or about 20 every second.

 

[JAJ]

I think you guys are mixing up heat soak and heat transfer. Thats like saying im just as hot in the shade vs in the sun even though the air temp is the same, but we all know the heat transfer is much greater in direct sun light due to radiant heat.


I cannot vouch for quality or how much heat it can reflect but the idea is not simple insulation like in your house.

You're right to a point - the amount of heat transfer into the intake charge increases as the temperature difference rises, so as the air flow cools off, more heat flows in. However, as a mechanical engineer once explained, a thick boiler wall transmits the same heat as a thin one for a given temperature difference, his point being that insulation only has a transitory delaying effect on heat flow. Think of the space shuttle insulation tiles - they block the heat of re-entry for long enough to complete the job, but if re-entry took ten times longer the inside of the shuttle would melt.

So, with that said the real issue here is that when you want power, the airflow is so fast that it's hard for the manifold to heat the air enough to matter - the air is in the manifold for one twentieth of a second and then it passes into the cylinder. The density, which is what matters, is a function of absolute (Kelvin) temperature, so a 1 degree Celsius increase in temperature makes a one-in-three-hundred (0.3%) difference. It's just not enough to matter. That's the road racing situation. As Dave says, drag racing is a whole different thing.

 

[zeroescape]

Everything you said only applies to convection and conduction, not radiant. A reflective surface can reflect considerable amount of heat even when both sides of the reflective surface are the same temp. The surface of the intake would be cooler, like a previous post results, but i do agree with you the amount of time spent inside the intake is not long enough to see considerable gains. However ive seen many high end race teams employ a gambit of heat control devices, but they have tools, budget, and time to run tests to figure out what provides gains. Insulating an entire intake system may yield a few hp but in racing world thats a easy gain.