Also not wanting to argue further, but an enclosed engine compartment is not an open enviroment in any form. It is definitely finite.
And on that car, it has to be an airflow issue. It was my daily driver at the time, and the stock/no hood/ louvered hood was the only thing that was different, before during and after the hood was being punched.
as for the original question, I dont think it makes much difference. The "ramp" of the louver is still in the same direction. Just the slit is before or after it. Another cool thing I've hread about louvers is that they use them on LSR Hot Rods on the decklids as vortex generators. Not to get rid of the air in the trunk, but to help the laminair flow at the back off the car...
Back to the original question, with them the way are, it is most likely to keep the hood from blowing off. think about the hood latches in the early days, and for racing they added a nice leather belt!
I used to see car hoods raised up at the back... they'd stick washers or shims between the hinges and hood, and they'd usually have a 2" gap between the hood and cowl. Was that very effective for cooling? Would cutting some notches from the hood where it meets the cowl help?
Yeah, We got kicked out of impound the first day for so gills in front of the rear wheel they thought we were trying to use as aero help...not allowed in modified roadster
100% wrong. Can you hook an airhose to your engine compartment and read how much pressure you have???!??!!? NO ....So its sure as hell not infinite!
While I've heard of using them reversed as Vortex generators, I didn't know that would get you booted. Would they have let you run them in the traditional fashion with the louvers out and venting? The vortex generator concept is some thing that I admit to not being very well versed in.
No, in Modified roadster it states you are not supposed to have any body modifications from the firewall back...this is usually fairly loose and is generally meant that you cannot section or narrow the body, smooth the door edge reveals etc....this was just a ribbed panel that we had used years ago when we ran it with a radiator as its inlet. it was completely non functional. It was just a ******* match between some of the officials as our cars have been somewhat controversial. They said we were using it as a escape for a high pressure area in front of the wheel....we tore it off, made some flat plates and went faster...
The area at the base of the windshield is a high pressure area. Thats why they draw the air from there for the heaters in production cars. So raising the hood a bit in the back may help to get rid of the heat if you are in a traffic jam, but once the car is moving it will force more air inside the engine compartment. Which will probably reduce the flow through the radiator. Besides the fan ( if the car has one ) the flow through the radiator relies on the pressure difference beween the two sides of it ( front and back ) The grille area is a high pressure area. The higher the pressure inside the engine compartment, the less the difference, which gives less flow. Another thing to keep an eye on is to make sure heated air coming through the radiator cant be ****ed back up and forced trough the radiator again. It being there will reduce the cool air that could flow through, which will also reduce the efectiveness of the Radiator.
I've got a damnned headache reading all this . . . and yet, I've enjoyed it at the same time! Louvers, no louvers. Hood, no hood. What the ****, how about let's talk electric fans. Stuck in traffic? Electric fan. Seems the conversation is really reduced to keeping the engine cool, which means maximum radiator efficiency. Yes? Great question, The37Kid.
Seems to me, radiator efficiency has to do with how good it is transfering the heat from the coolant to the air. ( which is affected by the material the Rad is made off, and even its color ) This is more about the airflow, and the tricks to change it ( or improve it ) Using louvers is one of those tricks
Point taken. Need to shut up and listen some more. What seems intuitive is not necessarily correct. Still a bit confused on the answer. Better, or worse? No difference? Oh ****, I need a drink!
Henry put angled tow boards in to help air out the bottom... has to be true- he was too che--frugal to put that there if a flat firewall would have cooled te same...
Chris posted this photo today or the Don Orosco restored roadster with the type of reversed louvers I had in mind when I started this thread. Thanks Chris!
This is all I could think of. Primer, primer, paint, color sand, polish, wax.........it never ends. If you louver the hood and don't have a good seal on your air cleaner bolt, your engine can fill up with water and hydraulically lock. Never again.
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