vented carbon hoods
05-14-2010, 02:16 PM
#52
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I have NO idea what your'e talkin' about. 
05-14-2010, 03:08 PM
#53
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Also, what happened to the myth that our OEM hoods couldn't be vented? There was a fairly in depth conversation about it a couple years back, I believe someone even tried it without success. Anyone want to dig up the thread or remember what I am talking about?
05-14-2010, 04:16 PM
#54
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^This guy https://www.rx8club.com/showthread.p...ut+vents+hood? He actually ended up with a very small vent on the passenger side of his car you can see it i think if you go in his user profile and look at his pictures. It looks like he cut away the shock absorbing structure then made the vent so im sure its not as structurally sound.
Last edited by RX8YA; 05-14-2010 at 04:21 PM.
05-14-2010, 04:34 PM
#55
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Proper tools and it looks like we can vent our hood however we'd like. Structural integrity might start to suffer though...
I'm surprised I didn't finish following that thread back then, haha. I could have sworn I participated too lol
I'm surprised I didn't finish following that thread back then, haha. I could have sworn I participated too lol
05-14-2010, 04:42 PM
#56
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^ It definitely can be done ive seen a hood. Ill try and get the picture again from the s2k guy. The best proof is MM's hood i think the only limitation may be shape of the vent depending on how much of the structural material you are willing to sacrifice.
05-24-2010, 07:50 PM
#58
I have the seibon tsII hood with the gutters off. I didnt pay much attention to ECT or OIL Temp data enough before to know if there was any improvement in the cooiling department. I suspect there is some and at the least, it cant hurt.
However, from talking with several race teams at local track days, reading post by a rx8 race team on this forum, reading aero books and having a former lotus aero engineer look at my car with the hood installed I have come to the conclusion that the biggest advantage of the vented hood is reduced front end lift, second small advantage is better airflow across the radiator at high speed.
Both are acomplished by venting air, or more specificaly venting air pressure out of the hood instead of being trapped under the hood waiting to escape out the bottom of the car or into the wheel wells. When the air in trapped under the hood it builds up pressure and causes lift and drag, when it goes under the vehicle it increases air pressure and causes lift and drag, when the air enters the wheel wells it creates a big air pocket causing lift and drag.
For cooling benefits any trapped and pressurized air reduces cooling capabilites. Trapped/pressurized air under the hood makes it difficult for air to pass through the radiator. The trapped air in the wheel wells also makes it difficult for the brakes/tires to be cooled and the air to pass through the oil coolers which vent into the wheel wells. I dont think you get very much air from the engine bay into the wheel wells , however if you could vent the wheel wells I believe you would get both aero and cooling benefits. (I plan on testing this theory at some point soon)
Some people are going to argue that mazda designed the vehicle with hours of cad and wind tunel time and there is no benefit to cooling or aero by adding vents. To those people I say, what fantasy world do you live in? It is very obvious that car manufactors have one thing in mind, Profit. If they can get cooling and COD numbers good enough to sell a car, they will stop looking for improvments. Vented hoods and functional brake vents cost money and sell no better then fake vents or scoops. 99% of the puplic buys based on the WOW factor. No sellsman ever sold a car by explaining aero dynamics and cooling to a customer.
Lastley, most aero kits you buy have no been tested and in most cases will hurt your COD, not improve it. But if you read a few books, take a long look at your car and try thinking outside the box a little. You will see that there are improvments that can be made. Just start small, do one thing at a time and test it out. Worse thing that can happen is you learn something about aerodynamics.
Oh and I get almost no water into my engine bay with the vented hood.
However, from talking with several race teams at local track days, reading post by a rx8 race team on this forum, reading aero books and having a former lotus aero engineer look at my car with the hood installed I have come to the conclusion that the biggest advantage of the vented hood is reduced front end lift, second small advantage is better airflow across the radiator at high speed.
Both are acomplished by venting air, or more specificaly venting air pressure out of the hood instead of being trapped under the hood waiting to escape out the bottom of the car or into the wheel wells. When the air in trapped under the hood it builds up pressure and causes lift and drag, when it goes under the vehicle it increases air pressure and causes lift and drag, when the air enters the wheel wells it creates a big air pocket causing lift and drag.
For cooling benefits any trapped and pressurized air reduces cooling capabilites. Trapped/pressurized air under the hood makes it difficult for air to pass through the radiator. The trapped air in the wheel wells also makes it difficult for the brakes/tires to be cooled and the air to pass through the oil coolers which vent into the wheel wells. I dont think you get very much air from the engine bay into the wheel wells , however if you could vent the wheel wells I believe you would get both aero and cooling benefits. (I plan on testing this theory at some point soon)
Some people are going to argue that mazda designed the vehicle with hours of cad and wind tunel time and there is no benefit to cooling or aero by adding vents. To those people I say, what fantasy world do you live in? It is very obvious that car manufactors have one thing in mind, Profit. If they can get cooling and COD numbers good enough to sell a car, they will stop looking for improvments. Vented hoods and functional brake vents cost money and sell no better then fake vents or scoops. 99% of the puplic buys based on the WOW factor. No sellsman ever sold a car by explaining aero dynamics and cooling to a customer.
Lastley, most aero kits you buy have no been tested and in most cases will hurt your COD, not improve it. But if you read a few books, take a long look at your car and try thinking outside the box a little. You will see that there are improvments that can be made. Just start small, do one thing at a time and test it out. Worse thing that can happen is you learn something about aerodynamics.
Oh and I get almost no water into my engine bay with the vented hood.
06-23-2010, 07:35 PM
#60
I have the seibon tsII hood with the gutters off. I didnt pay much attention to ECT or OIL Temp data enough before to know if there was any improvement in the cooiling department. I suspect there is some and at the least, it cant hurt.
However, from talking with several race teams at local track days, reading post by a rx8 race team on this forum, reading aero books and having a former lotus aero engineer look at my car with the hood installed I have come to the conclusion that the biggest advantage of the vented hood is reduced front end lift, second small advantage is better airflow across the radiator at high speed.
Both are acomplished by venting air, or more specificaly venting air pressure out of the hood instead of being trapped under the hood waiting to escape out the bottom of the car or into the wheel wells. When the air in trapped under the hood it builds up pressure and causes lift and drag, when it goes under the vehicle it increases air pressure and causes lift and drag, when the air enters the wheel wells it creates a big air pocket causing lift and drag.
For cooling benefits any trapped and pressurized air reduces cooling capabilites. Trapped/pressurized air under the hood makes it difficult for air to pass through the radiator. The trapped air in the wheel wells also makes it difficult for the brakes/tires to be cooled and the air to pass through the oil coolers which vent into the wheel wells. I dont think you get very much air from the engine bay into the wheel wells , however if you could vent the wheel wells I believe you would get both aero and cooling benefits. (I plan on testing this theory at some point soon)
Some people are going to argue that mazda designed the vehicle with hours of cad and wind tunel time and there is no benefit to cooling or aero by adding vents. To those people I say, what fantasy world do you live in? It is very obvious that car manufactors have one thing in mind, Profit. If they can get cooling and COD numbers good enough to sell a car, they will stop looking for improvments. Vented hoods and functional brake vents cost money and sell no better then fake vents or scoops. 99% of the puplic buys based on the WOW factor. No sellsman ever sold a car by explaining aero dynamics and cooling to a customer.
Lastley, most aero kits you buy have no been tested and in most cases will hurt your COD, not improve it. But if you read a few books, take a long look at your car and try thinking outside the box a little. You will see that there are improvments that can be made. Just start small, do one thing at a time and test it out. Worse thing that can happen is you learn something about aerodynamics.
Oh and I get almost no water into my engine bay with the vented hood.
However, from talking with several race teams at local track days, reading post by a rx8 race team on this forum, reading aero books and having a former lotus aero engineer look at my car with the hood installed I have come to the conclusion that the biggest advantage of the vented hood is reduced front end lift, second small advantage is better airflow across the radiator at high speed.
Both are acomplished by venting air, or more specificaly venting air pressure out of the hood instead of being trapped under the hood waiting to escape out the bottom of the car or into the wheel wells. When the air in trapped under the hood it builds up pressure and causes lift and drag, when it goes under the vehicle it increases air pressure and causes lift and drag, when the air enters the wheel wells it creates a big air pocket causing lift and drag.
For cooling benefits any trapped and pressurized air reduces cooling capabilites. Trapped/pressurized air under the hood makes it difficult for air to pass through the radiator. The trapped air in the wheel wells also makes it difficult for the brakes/tires to be cooled and the air to pass through the oil coolers which vent into the wheel wells. I dont think you get very much air from the engine bay into the wheel wells , however if you could vent the wheel wells I believe you would get both aero and cooling benefits. (I plan on testing this theory at some point soon)
Some people are going to argue that mazda designed the vehicle with hours of cad and wind tunel time and there is no benefit to cooling or aero by adding vents. To those people I say, what fantasy world do you live in? It is very obvious that car manufactors have one thing in mind, Profit. If they can get cooling and COD numbers good enough to sell a car, they will stop looking for improvments. Vented hoods and functional brake vents cost money and sell no better then fake vents or scoops. 99% of the puplic buys based on the WOW factor. No sellsman ever sold a car by explaining aero dynamics and cooling to a customer.
Lastley, most aero kits you buy have no been tested and in most cases will hurt your COD, not improve it. But if you read a few books, take a long look at your car and try thinking outside the box a little. You will see that there are improvments that can be made. Just start small, do one thing at a time and test it out. Worse thing that can happen is you learn something about aerodynamics.
Oh and I get almost no water into my engine bay with the vented hood.
Agreed 100%
09-28-2010, 09:55 PM
#62
I zoom therefore I am.
would be interesting to see if it made any real difference to engine temps.
Air takes the path of lease resistance and there's lots of wide open spaces for the air to come from that would be nowhere near the engine.
Air takes the path of lease resistance and there's lots of wide open spaces for the air to come from that would be nowhere near the engine.
09-29-2010, 03:37 AM
#64
I seriously doubt any CF hood is wind tunnel tested to help increase downforce, it might help provide more cooling and reduce pressure underneath the hood but I dont see how the design would increase downforce at all.
A cool tip for anyone who cant pay for wind tunnel testing, its pretty simple and will give you a decent idea where air goes.
Basically wait till it hits in the 50 degrees and get up around 7am, your car should have accumulated condensation all over your car. Basically warm up your car and take her for a quick spin down the highway to 80mph and stop and see where there is still water. You will see more water on the hood and hardly any on the door panels etc.
Its a cool trick to see where air actually flows...
A cool tip for anyone who cant pay for wind tunnel testing, its pretty simple and will give you a decent idea where air goes.
Basically wait till it hits in the 50 degrees and get up around 7am, your car should have accumulated condensation all over your car. Basically warm up your car and take her for a quick spin down the highway to 80mph and stop and see where there is still water. You will see more water on the hood and hardly any on the door panels etc.
Its a cool trick to see where air actually flows...
10-02-2010, 11:05 AM
#69
I've been dreaming of it for a long time. I just got lucky/unlucky in getting it. My car was in an accident, destroyed my authentic Mazdaspeed bumper in the process. Well, since they don't make them anymore, it was taking too long to get, so I had to order a replica. However, since the insurance company paid for the MS one, I had a chuck of change left over, so I told the body shop to order the replica, and the CF Hood. With the work the bodyshop's doing to the bumper, you won't be able to tell the difference from the authentic, hopefully.
Zombies.
Zombies.
10-02-2010, 05:52 PM
#70
SiNoEsRotorNoEsMotor
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still has the vent covers..i might take them off tomorrow, it has to make a difference not having all that HOT air traped under the stock hood imo
Last edited by ManyRX; 10-02-2010 at 05:58 PM.
10-02-2010, 05:55 PM
#71
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You have no idea!
San Jose..............average rainfall = 15.08 Inches
Melbourne...........average rainfall = 49.29 inches
Last edited by Mazurfer; 10-02-2010 at 05:59 PM.
10-02-2010, 10:25 PM
#72
I zoom therefore I am.
water falling down is water falling down. I'm not talk light misting but rather inches per hour during a storm or two. It's your own fault for living in god's waiting room (aka florida), move to less wet climates sir
10-03-2010, 08:52 AM
#73
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^......
God's waiting room...........I like that! Contrary to popular belief, we aren't all cotton tops(aka Q-tips)!
God's waiting room...........I like that! Contrary to popular belief, we aren't all cotton tops(aka Q-tips)!
Last edited by Mazurfer; 10-03-2010 at 08:59 AM.
10-16-2010, 09:26 AM
#74
if everyone is worried about water getting in just buy a car cover or garage your car. barely any water gets in while your driving, and as far as at the car wash, i cover the air filter and electrical parts with plastic bags and just remove them afterwords. even after a car wash you see minimal water getting into the vents
10-16-2010, 08:04 PM
#75
If the car is sitting still outside in the rain it will get come water, but the angle of the vents keeps it to a minimum.
When driving, the air passing over will pull both the air out and keep water from getting in. Besides the fact that nothing under the vents will be damaged by a little water.
When driving, the air passing over will pull both the air out and keep water from getting in. Besides the fact that nothing under the vents will be damaged by a little water.