Combating the heat

[mike the snake]

I'm going to get the cord so I can plug my laptop into my ECU. I'll be able to read IAT's then.

[cdrazic93]

http://ft86speedfactory.com/rksport-...hood-1496.html

Anybody have experience with this hood?

[Dipstik-sportech]

That hood will probably hinder more than help air flow. You want air to come out of the engine bay not force more into it.

The Frozen North

[SirBrass]

Originally Posted by Dipstik-sportech

That hood will probably hinder more than help air flow. You want air to come out of the engine bay not force more into it.

The Frozen North

Think of the engine bay the way your would the inside of a computer case: you have venting fans to push air out, but the real work horses are your blower fans which push cooler air IN, thus creating a cool air stream across hot components and moving fresh air into the interior space. The venting fans just help keep the air moving out.

Same here, and the principle is the same, but using the vehicle's velocity as the "fan": evacuate the hot interior air and replace it constantly with cooler outside air.

[Dipstik-sportech]

Yes but that air has to then escape the bay. That hood style just forces more air in and actually might pressurise it enough to actually decrease air flow across the radiator due to pressure equalisation. What you need is a rear facing vent or a slash cut style to create a low pressure area over the hood drawing the hot air out

The Frozen North

[Sellout]

Originally Posted by SirBrass

Think of the engine bay the way your would the inside of a computer case: you have venting fans to push air out, but the real work horses are your blower fans which push cooler air IN, thus creating a cool air stream across hot components and moving fresh air into the interior space. The venting fans just help keep the air moving out.

Same here, and the principle is the same, but using the vehicle's velocity as the "fan": evacuate the hot interior air and replace it constantly with cooler outside air.

You've already got air coming in, it comes through the radiator in front. You don't need anymore air going in. You need more air going out.

[SirBrass]

Originally Posted by Sellout

You've already got air coming in, it comes through the radiator in front. You don't need anymore air going in. You need more air going out.

It's already been pointed out that it's still a choke point for airflow.

If you've got air coming in, you've got air going out. The more air coming in, the more air that is going out. Otherwise your engine bay would inflate like a balloon and pop.

[Sellout]

Originally Posted by SirBrass

It's already been pointed out that it's still a choke point for airflow.

If you've got air coming in, you've got air going out. The more air coming in, the more air that is going out. Otherwise your engine bay would inflate like a balloon and pop.

That's exactly the point. Maybe I should have worded it better. We have the POTENTIAL for all the airflow we could possibly need coming through the radiator, but we don't get that airflow because there's not enough places for the high pressure air under the hood/behind the radiator to get out. If the hot air can't get out, fresh air can't get in.

Adding places to get air IN doesn't help us. Not even a little bit. Because we need that air going through the radiator on its way into the engine bay.

[SirBrass]

Airflow will do that anyway. It's the air that is diverted around the radiator which could be used to blow out hot air.

A properly vented hood & an air ram on the aluminum skid plate could do that. Air there wasn't going to the radiator anyway.

On phone I am. Therefore, if mistakes I make, Frank Oz blame you should.

[steve99]

Originally Posted by SirBrass

Airflow will do that anyway. It's the air that is diverted around the radiator which could be used to blow out hot air.

A properly vented hood & an air ram on the aluminum skid plate could do that. Air there wasn't going to the radiator anyway.

On phone I am. Therefore, if mistakes I make, Frank Oz blame you should.

you need a pressure differential for air to flow. A forward facing hood scoop or "ram air" skid plate, will most likely increase the air pressure in the engine bay behind the radiator and hence reduce the flow of air through the radiator. If you look at the stock car its quite carefully designed to make sure that the maximum amount of air flows through the radiator and not around it.

[steve99]

Originally Posted by Dipstik-sportech

Yes but that air has to then escape the bay. That hood style just forces more air in and actually might pressurise it enough to actually decrease air flow across the radiator due to pressure equalisation. What you need is a rear facing vent or a slash cut style to create a low pressure area over the hood drawing the hot air out

The Frozen North

correct, ensuring is actually a a low pressure area would be the key.

[cdrazic93]

I still think actually making the side vents functional is the cheapest and best way to release the trapped hot air in the engine bay.

[mike the snake]

Our intercoolers cover almost the entire front grill, which I think might also restrict a lot of the air that normally would flow through the radiator.

Tomorrow, I am planning on cutting on my metal skidplate to enlarge the engine bay exhaust opening size, and adding my rubber "trip strips", which I hope will help pull extra air from the engine bay.

I want to retain some of the protection of the skidplate, otherwise I'd just remove the skidplate altogether.

This, coupled with the holes I've cut into the front bumper, I'm hoping will increase the air exchange.

I plan to do some "smoke bomb testing" after that.

[sidetrak06]

Does anyone have access to a thermal imaging camera? We can stop the speculating about where the heat is going and actually see it!

http://www.flir.com/thermography/ame...=830&col=61190

These things sell for $1,500 and are extremely useful for visualizing heat transfer and fluid dynamics. It seems to me that vendors such as Full Blown could greatly benefit from this relatively small investment and put some extremely powerful R&D to work to come up with innovative solutions to these heat issues. Simply modifications such as removing cowls and modifying skid plates could be visualized on a dyno run in minutes.