ok ive researched this a bit today but cant find anything conclusive.. now fitting bonnet spacers to a drift car may help to get some heat out but what about fitting them to a car that occasionally drifts but also is an everyday car that tends to do longish journeys at speed??. would they cause any issues???
it doesnt help with heat while drifting anyway so all it does is give people the impression your cars had a crash and the bonnet doesnt fit !! wouldnt bother as it looks shit but if you still want to do it then all u need is anything to space it out like washers or nuts
It can have the opposite effect. You get high pressure air at the base of the windscreen so if you lift the rear of the bonnet it forces air down. This creates a high pressure zone and can slow down air flow through the rad. The only reason to to this would be to get extra cool air into the induction system.
air flowing over the hood when speeding sucks air from under the hood...and from the engine bay.. that makes more air want to go through the radiator - engine bay - and out from the lifted side of your hood aerodynamicly is completely wrong not because of the lifted hood but because you force all the air to come out from a place not designed by factory this cause drag factor to increase like hell looks shity indeed... but cooler... not helpful when going sideways...
Low pressure area is localised. At the rear of the bonnet its high pressure forcing air in. If you want to imprive cooling (and looks) add vents to the bonnet just behind the radiator line.
if you want to see whats true lift the back of your bonnet(easily done) and put some strings under it so when driving you can see the strings moving... ok? thats what we did in aeronautics because we did not afford wind tunnels.... the picture you posted maybe right for this(mazda fc?) and at specific klms ok ? and still quite wrong do the experiment mate..(with the bonnet lifted! ) there is a huge difference at speed
You are wrong. the base of the windscreen is a HIGH pressure area on EVERY car. Thats why the car ventilation air is taken from this area, otherwise it would suck air out of the cabin! Do I need to find any more pictures?
If you lift the hood all the way around you may get some air escaping towards the front of the car. At the back the positive air pressure will blow down into the engine bay. Just lifting the back will just cause air to be forced down restricting airflow through the rad. more info on aerodynamics Race Car Design Tips and Information - Aerodynamics The ideal situation for cooling is air ducted in from below the bumper (very high pressure area) the vented on the top of the hood just behind the radiator
Did that years ago on my S13, its called tuft testing. The tufts along the rear edge of the bonnet got sucked down towards the engine bay, proving that its a high pressure area.
Would the pressures not be different for us been sideways rather than forwards? Just a thought, I'm no expert... not even an amateur
Interesting point. Maybe you should have a side mounted radiator! Now that would create some discussion.
Absolutely! but usualy this is when the engine is warming up anyway so you may actualy want it to warm up quickly. More important is the time you come screeming off the track then get stuck in parc ferme with your engine cooking. Some car manufacturers now use "funnels" that duct air from the exhaust manifold upward to vents on the bonnet or engine cover to alow hot air to escape when you are at a standstill. The Aston Martin One77 and Lotus Evora do that. Maybe there is a market for a gizmo that pops open and closes the rear of the bonnet on demand when you are stationary?
