Does CS Hood actually help air flow??

Does CS Hood actually help with airflow and/or heat release?

  • Definitely, a whole lot!

    Votes: 0 0.0%
  • Yes! BUT, only with airflow...

    Votes: 0 0.0%
  • Yes! BUT, only with heat release...

    Votes: 0 0.0%
  • Yes! BUT only in other aspects...

    Votes: 0 0.0%
  • Ehhh, it does help to some degree.

    Votes: 0 0.0%
  • Nope, to some degree, but hardly practical.

    Votes: 1 100.0%

  • Total voters
    1

toayoztan

Moderator
Alright, so I was talking with someone about this. We were wondering if the CS hood vent actually did anything to help the airflow through the intercooler/radiator through the motor, and of course out the vent? Does it even do anything to help "release" hot air out of the bay? His claim was that it doesn't do that very effectively. He also claims that the turbo sits right there under the vent, "blocking" a part of the flow. So i was wondering what you all thought?

Does anyone have any proof (don't know how you'd get this) or claims as to it actually helping with anything? To what degree is it effective/practical? If not with airflow or JUST airflow, what else does it do for any other aspects (such as heat release, etc)?

Oh and one more question, who made the CS Hood? Did TTE alone make it for CS, or did CS himself have any part in designing the hood?

Thanks for any input!

Bryan
 
I'd be willing to bet that it is better than using a non-CS/RC hood with a CS/RC bumper or using a non ST-185 hood. I have no proof of this of course, but it seems to make intuitive sense to me at least.
 

CMS-GT4

Active member
The press release mentions that the CS hood an bumper were wind tunnel tested for better areodynamics and airflow.
Also, I read on the board a very long time ago, that the st185 had heat problems while racing and that is what inspired the design of the CS hood. They were even having timing belt issues with heat that is where the scoop came from on the pass side of the vent.
 

grip addict

New member
after studying a little thermodynamics when i was nerding out with my pc hardcore, i found out that making air flow in one direction is a much better way to move heat out, than just jam in from all directions (ie top and front)
if you really want to pwn it just try to make a vacuum. either way though, heat always rises and out the top is the best solution for that-
i just wonder how efficient it is for the wta ic
 

pog0

New member
Either way I think it helps if you have both the bumper and the hood. The hood vent is angled down a bit so the air can go thru the bumper and out of the hood easier. If you just idle, you can see the amount of heat that is coming out of the hood. I would say it definitely helps.
 

___Scott___

Active member
Generally speaking...

Consider the air pressure at different locations, and you should conclude that having a vent in the hood will improve the airflow through the radiator/FMIC while the car is moving forward. It should be obvious that there will be a high pressure area (relative to ambient pressure) in front of the car. Air dams and side skirts, often used for downforce, produce a low pressure area under the car which provides an escape route for heated engine bay air. Since we don't have effective airdams/skirts, the engine bay can become a high pressure area which discourages air to flow through the radiator. The vent in the hood takes advantage of the Bernoulli effect which says that the faster air moves, the lower the pressure is. So fast moving air over the hood/vent provides an escape route for the heated engine bay air. The vent has an advantage when stopped/idling to allow rising heated air to escape vs. air dam/skirts that don't.

I always like a pic to illustrate how air flows over a car. This one was the closest I could find to the shape of an ST185:
jaguar.windtunnel.500.jpg
 

Simba

New member
The CS hood reduces drag significantly, as well as creates a low pressure area behind the lip of the vent, which in turn draws air through the IC core. However, without proper ducting (see, Ford GT, Ferrari Enzo), it's causing mostly hot air to be fed through the core from the engine and turbo.

The stock hood creates considerably more drag, but has the benefit of forcing cooler air directly through the core.

Hence, the stock hood probably offers significantly better core cooling, with more drag.

Were you to fab up proper ducting to get cold air from the nose of the car to the bottom of the IC core while using the CS hood, it would no doubt cool it better than the stock hood.
 

toayoztan

Moderator
omgitsroy326":3nwhhajt said:
this discussion is assuming that there's a fmic or wta right ?

Yep, both. However, you can discuss your claim for either fmic the or wta. Why can wta be included in this discussion? Because we're also looking at the aspect of heat release, and how effective this hood does that.

Obviously if you had TMIC, you should opt for the scoop, hands down heh.

Bryan
 

maxaud

Active member
I'm unsure who made the hood, but I would think a lot of time and consideration has gone into the actual design of it seeing as how they add'd stuff like the timing belt cooler because they found that the timing belts would melt in abusive rally'n. I would have to say that they went w/ as efficient design as they could .... I mean... why wouldn't they?
I think the hole over the turbo is a lot better then the turbo somewhere else. The air flow can cool the turbo and the heat from the turbo can escape through the rather then trying to find it's why out elsewhere.

my $.02
 

RedCelicaTRD

Moderator
Simba, are you saying the Ford GTs and Ferrari Enzos have such low frontal pressures that air flows backwards from the vent out the front?
 

maxaud

Active member
in an Emerging Engineering class that I took where we built electric cars for racing we were told that a common rule w/ scoops is that you need twice as much outlet as you have inlet or you will have poor flow and it won't be efficient.
 

Simba

New member
RedCelicaTRD":2rl6psa3 said:
Simba, are you saying the Ford GTs and Ferrari Enzos have such low frontal pressures that air flows backwards from the vent out the front?

No, I'm saying both cars have ducts which channel airflow from behind the rad to the hood vents. That makes them very efficient at moving air through the vents.

The AT with the CS hood doesn't have anything like that, so most all of the air getting forced through the rad at speed goes to low pressure immediately behind it, rather than remaining a high pressure flow as is the case with ducting.

Vents of the like really don't work very well on front-engine cars due to the lack of space for proper ducting.

My "fed through the core" comment was referring to a TMIC. If you're using a FMIC or WtA, the type of hood you use is completely irrelevant as it has absolutely no impact on flow through the rad/ic core.
 

maxaud

Active member
I would think you would have more flow through a FMIC w/ a RC/CS hood rather then a stock 184 or even a stock 185 hood
 

Simba

New member
You're not getting any more through the rad/ic area with a CS hood. The airflow immediately gets turbulent after the cores, then hits the brick wall that is the engine block.

The only way to prevent that is with ducting.
 

maxaud

Active member
was that a reply to my post? I would think you would get much more airflow w/ a cs/rc hood (not talking about tmic, that would just be stupid), it gives an out for air to go when a st185/184 hood would do nothing of the like.
 

Simba

New member
Yes. I've no doubt the CS vent allows a good deal of hot air to be sucked out of the engine bay, but there's no uniform flow to it. Without ducting, all of the air that flows in there is very turbulent, low pressure air that more or less goes where it pleases. There's nothing behind the rad allowing the cowl induction effect of the vent to actually help pull air through it.

From a cooling standpoint, I highly doubt the CS hood moves any more air through the rad, given the flow dynamics over the engine.

It's easy enough to prove either way. Just get yourself a bigass fan, an IC camera, and a smoke machine.
 
A

Anonymous

Guest
I have kinda an off topic question....

The side vents on a ST185 hood, do you think it would be better to flip them around so that the 2 side vents and the main scoop all face forward or not?
 
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