Hood Ventilation Ideas
#27
RotoRocks Powered
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#28
Banned
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I did it on mine and ran around with a laser thermometer for a few days.
When you are stopped, the heat pours out from that opening - which is not nice if you use the "fresh air" option on your A/C controls (I never do because I like to recirculate the new-car smell!). Temps there can be up to 160°F.
When you are moving, it "splatters" at a frequency that I suspect is regulated by some resonant effect tied to speed. I saw oscillations from ambient (around 104°F) up to 140°F.
Most importantly, it moved up my "break-over" ambient temp up from 107°F or so.
I can rage along at that ambient temp now, whereas before, I'd start to overheat with the A/C on and over 4000 RPM.
When you are stopped, the heat pours out from that opening - which is not nice if you use the "fresh air" option on your A/C controls (I never do because I like to recirculate the new-car smell!). Temps there can be up to 160°F.
When you are moving, it "splatters" at a frequency that I suspect is regulated by some resonant effect tied to speed. I saw oscillations from ambient (around 104°F) up to 140°F.
Most importantly, it moved up my "break-over" ambient temp up from 107°F or so.
I can rage along at that ambient temp now, whereas before, I'd start to overheat with the A/C on and over 4000 RPM.
#29
the shit starter
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if that space between the hood and wind shield is a escape route for hot air, than wouldn't cutting the triangle dip in the center of our hoods help more hot air get out of the engine bay?
I know the OP counted out cutting into the hood, and his idea sounds better/easier than mine. Although I would rather like too just control the height of the hood with a #'ed switch.
I know the OP counted out cutting into the hood, and his idea sounds better/easier than mine. Although I would rather like too just control the height of the hood with a #'ed switch.
#30
Metatron
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When your are moving the back of the hood becomes a high pressure area, and air would move IN, exactly what you don't need.....
When standing still it would let hot air out, but cripple your a/c inlet, so it would be for hard core racers only. First prove your "hardness" by removing the a/c to save weight. Then the open-at-the-rear hood means something.
S
When standing still it would let hot air out, but cripple your a/c inlet, so it would be for hard core racers only. First prove your "hardness" by removing the a/c to save weight. Then the open-at-the-rear hood means something.
S
#32
Nope
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yeah, I removed the rubber stripe from the back of my hood as well and I can see the heat waves poor out it now. And my oil temps are about 5-degrees cooler, and water temps about 6-7 degrees cooler at speed and around 3-4 degrees cooler while in traffic, confirmed with a sCANalyser.
It takes 2 seconds to pull off the stripe, and you can put it back quite easily if you want to. And it doesn't make anything look different.
Vents in the triangle is what the Veilside hood does.
It takes 2 seconds to pull off the stripe, and you can put it back quite easily if you want to. And it doesn't make anything look different.
Vents in the triangle is what the Veilside hood does.
#33
printf("</%i pistons",3);
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Fabricate a vent that channels air through the little square holes in the frame (located just behind and above the tires) and out the fender vents. That will satisfy your desire for cooler engine temps, and ½ this board's desire to have functional fender vents
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
#34
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the optimal place for a vent is somewhere before or in the front of the triangle in the hood. Its where the flow seperates from the body (just wash your car and take it for a spin....) and can provide the best flow from the engine bay being in the area between the airbox/battery/ecu area and engine
#35
RotoRocks Powered
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I found a solution, and it works simply fantastic!
I even tried to switch back an forth to make sure the difference is there and I am not imagining things, and hell yes. It works great whether at high speed or stand still.
As MM suggested I removed the rubber stripe, and on top of it to increase the opening, glued in two plastick blocks about 3/4" tall, so whe the hood closes, the blocks push thecurve of it up a little, making the opening much larger.
That is it. Solved the problem of overheating right up. No more need for the 800 hood.
Costs $0.00 :-) and looks great.
I may post a coule of pics just to show where I had added the plastick pieces, if anyone really needs it.
Thanks everyone for your help.
I even tried to switch back an forth to make sure the difference is there and I am not imagining things, and hell yes. It works great whether at high speed or stand still.
As MM suggested I removed the rubber stripe, and on top of it to increase the opening, glued in two plastick blocks about 3/4" tall, so whe the hood closes, the blocks push thecurve of it up a little, making the opening much larger.
That is it. Solved the problem of overheating right up. No more need for the 800 hood.
Costs $0.00 :-) and looks great.
I may post a coule of pics just to show where I had added the plastick pieces, if anyone really needs it.
Thanks everyone for your help.
#38
Rotary , eh?
iTrader: (1)
I think you wouldn't have to be a hardcore racer to appreciate more air cooling. I bet anyone that runs the oil temps upwards of the 260s would find this useful.
#39
RotoRocks Powered
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Here in South FL the FL turnpike it is very common to see people do 100 MPH and more during the rush hour. when you are going 80, it just feels slow, and cars are catching on to you and begin to pass.
At this speeds, usually if I go into boost (which is happening instantly, as soon as I open the throttle), the coolant temps would get close to a 100C in a matter of seconds. So I had to be real careful not to overdo it.
Today I tried it with the new mode...
I just couldn't get it there.
I was trying really hard to get the engine to go hot.
only driving it in 2nd gear at 8K+ rpm and around -15 - 20 HG with AF around 15.3-15.7 for probably a minute or more it finally got hot.
(By the way, I fixed that, and added fuel to get the AF to 14 in that area
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
And in Idles, it just doesn't get hot anymore.
Oh by the way, I would like to say a special thanks to MM.
If it wasn't for him, I would have probably dropped at least a 100 bucks getting the parts to get it to automatically open (if not more).
Yes it would have worked, and it would be a cool thing to watch your hood rise while you drive, but I don't care. All I wanted was to get it to run cooler, so thanks MM.
#40
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Oh by the way, I would like to say a special thanks to MM.
If it wasn't for him, I would have probably dropped at least a 100 bucks getting the parts to get it to automatically open (if not more).
Yes it would have worked, and it would be a cool thing to watch your hood rise while you drive, but I don't care. All I wanted was to get it to run cooler, so thanks MM.
If it wasn't for him, I would have probably dropped at least a 100 bucks getting the parts to get it to automatically open (if not more).
Yes it would have worked, and it would be a cool thing to watch your hood rise while you drive, but I don't care. All I wanted was to get it to run cooler, so thanks MM.
#46
Registered
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good for you...
now look at what an average aerodynamic profile looks like and see the flow boundary leave the hood around the 1/3 of the way and learn the reason for that departure from the hood is a high pressure vortex at the cowl area...
![](http://a332.g.akamai.net/f/332/936/12h/www.edmunds.com//media/roadtests/firstdrive/2007/nissan.350z.nismo/07.nissan.nismo.z.misc.500.jpg)
and then look at a functional cowl induction hood and how it directs air from the cowl directly into the carberator... wouldn't make sense to put an intake in an area where air is drawing away now whould it?
now look at what an average aerodynamic profile looks like and see the flow boundary leave the hood around the 1/3 of the way and learn the reason for that departure from the hood is a high pressure vortex at the cowl area...
![](http://a332.g.akamai.net/f/332/936/12h/www.edmunds.com//media/roadtests/firstdrive/2007/nissan.350z.nismo/07.nissan.nismo.z.misc.500.jpg)
and then look at a functional cowl induction hood and how it directs air from the cowl directly into the carberator... wouldn't make sense to put an intake in an area where air is drawing away now whould it?
![](http://www.glasstek.com/Gallery/6566impala2CIHD2.jpg)
#48
RotoRocks Powered
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I'd give a damn if it didn't work, and made things worse, but it works, whether by pulling cold air into the hood, or sucking hot air it out. Who cares? As long as it works and it keeps the engine cooler it is all that matter to me.
#49
Carbonormous
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Amemiya make a $2-300 solution depending on carbon or fro. You can see from the bottom pic it vents out the back as well.
http://www.re-amemiya.co.jp/commodit...59858&scd=9295
http://www.re-amemiya.co.jp/commodit...59858&scd=9295
![](http://www.re-amemiya.co.jp/commodity/image/01_rx_8_aero/06_rx_8_bonbon_all.jpg)
Last edited by savedsol; 08-02-2007 at 09:16 AM.