Hood Ventilation Ideas
09-12-2007, 02:03 AM
#251
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MazdaManiac: can you just give a summary of the conditions you are referring to?
my position is that this mod is effective where driving is at a speed where the pressure at the base of the windscreen is not higher than that under the hood (or a significant portion of it is like that, e.g. stop-go traffic, cool down laps at track).
As for people discounting the Volvo pressure/streamline picture because it isn't of an RX8, I've seen enough similar pictures to know it would be approximately the same for the volvo, for an Rx8, for a Supra and for a NASCAR.
my position is that this mod is effective where driving is at a speed where the pressure at the base of the windscreen is not higher than that under the hood (or a significant portion of it is like that, e.g. stop-go traffic, cool down laps at track).
As for people discounting the Volvo pressure/streamline picture because it isn't of an RX8, I've seen enough similar pictures to know it would be approximately the same for the volvo, for an Rx8, for a Supra and for a NASCAR.
09-12-2007, 02:12 AM
#252
Why doesn't anyone get that?
On an airplane wing, which force is a greater contributor of lift:
1) The low pressure area above the wing
2) The high pressure area below the wing
If you do not have at least 40 hours in your log book, consider that a rhetorical question.
09-12-2007, 06:47 AM
#254
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09-12-2007, 06:54 AM
#255
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3) airflow circulation around the wing
If you don't have 3 credit hours from a 300 level advanced Fluid Dynamics class and studied and tested the design of airplane wings - consider youself pwn3d
Last edited by r0tor; 09-12-2007 at 07:00 AM.
09-12-2007, 10:15 AM
#257
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Sure it could work, if the new hood opening is eliminating some under hood action (air flow or pressure) that was limiting the flow through the radiator.
That is why you go with what works. Air flow and turbulence is funny. Look at the years of arguing about truck tailgates and the drag associated with them being up or down (and that would seem to be clear cut!).
I would be concerned additional lift or drag after this change. But knowing MM, that has been tested and found to be minimal.
That is why you go with what works. Air flow and turbulence is funny. Look at the years of arguing about truck tailgates and the drag associated with them being up or down (and that would seem to be clear cut!).
I would be concerned additional lift or drag after this change. But knowing MM, that has been tested and found to be minimal.
09-12-2007, 10:19 AM
#259
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I was suggesting a more practical test....
Aerodynamics is not a cut and dry science or wind tunnels would not exist.
Show me a link concerning aerodynamics and the internals of engine compartments and we might have more to talk about.
But I get MM's attitude towards this discussion.
Aerodynamics is not a cut and dry science or wind tunnels would not exist.
Show me a link concerning aerodynamics and the internals of engine compartments and we might have more to talk about.
But I get MM's attitude towards this discussion.
Last edited by jeffe19007; 09-12-2007 at 10:22 AM.
09-12-2007, 10:24 AM
#260
RotoRocks Powered
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I did. I performed a very thorough dynamics testing on my car before and after.
Here are the results:
I run 140MPH before the mod, and 140 MPH after the mod on a wide and open highway stretch. Car feels the same.
Nice, tight and solid.
The only difference, the first time I came out of boost and my temp gauge was blinking red with temps ovet 100C like out of it's mind.
The second time it was 98C and not even a blink.
How's that for a test?
He heh he he he
With that, I couldn't give a rats *** where that air comes in or comes out. it could be coming out of Bin Ladden's ******* for all I care, as long as the coolant temps stay at bay, and the car doesn't get airborne.
Here are the results:
I run 140MPH before the mod, and 140 MPH after the mod on a wide and open highway stretch. Car feels the same.
Nice, tight and solid.
The only difference, the first time I came out of boost and my temp gauge was blinking red with temps ovet 100C like out of it's mind.
The second time it was 98C and not even a blink.
How's that for a test?
He heh he he he
With that, I couldn't give a rats *** where that air comes in or comes out. it could be coming out of Bin Ladden's ******* for all I care, as long as the coolant temps stay at bay, and the car doesn't get airborne.
Last edited by rotorocks; 09-12-2007 at 10:45 AM.
09-12-2007, 10:34 AM
#261
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I did. I performed a very thorough dynamics testing on my car before and after.
Here are the results:
The only difference, the first time I came out of boost and my temp gauge was blinking red with temps ovet 100C like out of it's mind.
The second time it was 98C and not even a blink.
How's that for a test?
He heh
Here are the results:
The only difference, the first time I came out of boost and my temp gauge was blinking red with temps ovet 100C like out of it's mind.
The second time it was 98C and not even a blink.
How's that for a test?
He heh
you might have found a great way at reducing cooling enough to kick on your fans more often
09-12-2007, 10:43 AM
#262
RotoRocks Powered
Thread Starter
You are like my wife when she has PMS. Just can't STFU
09-12-2007, 10:52 AM
#263
Power!!
Now who's trying to be a rocket scientist and doesn't know what they're talking about. You bought a Turbonator didn't you.
09-12-2007, 10:58 AM
#264
RotoRocks Powered
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09-12-2007, 11:05 AM
#266
RotoRocks Powered
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Actually it is a 1/2"
You are not paying attention
You betcha it will.
Just for kicks and giggles try to calculate the size of the opening based on the width of the hood. It is freaking big. How much air can be flown through that hole do you think?
You are not paying attention
You betcha it will.
Just for kicks and giggles try to calculate the size of the opening based on the width of the hood. It is freaking big. How much air can be flown through that hole do you think?
09-12-2007, 11:36 AM
#268
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intersteing thing about this whole discussion-
i read a quote from Jim Mederer recently about how Mazda has shown less and less ability(or has made more styling over substance decisions) over the years between rx-7s and rx-8s to get proper good airflow thru the radiator and that he/they at Racing Beat have found on the 3rd gen and the 8 that a splitter/diverter spoiler thing that created better flow to/thru the radiator/engine bay made a huge difference in cooling efficiency/keeping the temps down.
now to just find it again.
maybe ill just email jim.
i read a quote from Jim Mederer recently about how Mazda has shown less and less ability(or has made more styling over substance decisions) over the years between rx-7s and rx-8s to get proper good airflow thru the radiator and that he/they at Racing Beat have found on the 3rd gen and the 8 that a splitter/diverter spoiler thing that created better flow to/thru the radiator/engine bay made a huge difference in cooling efficiency/keeping the temps down.
now to just find it again.
maybe ill just email jim.
09-12-2007, 12:16 PM
#270
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intersteing thing about this whole discussion-
i read a quote from Jim Mederer recently about how Mazda has shown less and less ability(or has made more styling over substrance decisions) over the years between rx-7s and rx-8s to get proper good airflow thru the radiator and that he/they at Racing Beat have found on the 3rd gen and the 8 that a splitter/diverter spoiler thing that created better flow to/thru the radiator/engine bay made a huge difference in cooling efficiency/keeping the temps down.
now to just find it again.
maybe ill just email jim.
i read a quote from Jim Mederer recently about how Mazda has shown less and less ability(or has made more styling over substrance decisions) over the years between rx-7s and rx-8s to get proper good airflow thru the radiator and that he/they at Racing Beat have found on the 3rd gen and the 8 that a splitter/diverter spoiler thing that created better flow to/thru the radiator/engine bay made a huge difference in cooling efficiency/keeping the temps down.
now to just find it again.
maybe ill just email jim.
09-12-2007, 12:55 PM
#271
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intersteing thing about this whole discussion-
i read a quote from Jim Mederer recently about how Mazda has shown less and less ability(or has made more styling over substrance decisions) over the years between rx-7s and rx-8s to get proper good airflow thru the radiator and that he/they at Racing Beat have found on the 3rd gen and the 8 that a splitter/diverter spoiler thing that created better flow to/thru the radiator/engine bay made a huge difference in cooling efficiency/keeping the temps down.
now to just find it again.
maybe ill just email jim.
i read a quote from Jim Mederer recently about how Mazda has shown less and less ability(or has made more styling over substrance decisions) over the years between rx-7s and rx-8s to get proper good airflow thru the radiator and that he/they at Racing Beat have found on the 3rd gen and the 8 that a splitter/diverter spoiler thing that created better flow to/thru the radiator/engine bay made a huge difference in cooling efficiency/keeping the temps down.
now to just find it again.
maybe ill just email jim.
09-12-2007, 06:58 PM
#272
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I shudder to think at the time and expense to model, mesh and run a CFD simulation on a FULLY modelled car including engine bay. Wind tunnels are just easy for some stuff, and a good way to verify what you've designed.If OEMs designed cars to have vented hoods from the factory they could probably do a better job packaging components so everything was properly ducted out, rather than like aftermarket hoods that just have holes placed semi-randomly (and getting dirt/water on engine covers)
09-12-2007, 07:58 PM
#273
Power!!
Yes I'd love to have a Lotus Elise like setup where the airflow out of the radiator was ducted directly up and out through a screen in the hood. No more engine compartment airflow discussions needed.
09-12-2007, 09:17 PM
#274
RotoRocks Powered
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Talking about discussions: this thread went like HOLY ****!!!! LOL
people left and will be "sucking in" the air at high speeds inside their hoods and disrupting the radiator air flow, causing fans to come on more frequently. lots of fun...
By the way, loved the idea. +5 for inventing a new angle to the argument.
people left and will be "sucking in" the air at high speeds inside their hoods and disrupting the radiator air flow, causing fans to come on more frequently. lots of fun...
By the way, loved the idea. +5 for inventing a new angle to the argument.
