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Dont some of the EVO models have rear facing vents?

But vents in most applications vents are a joke and make automotive engineers laugh when goons with no idea put them in. Even many factory vents serve not purpose. In some cases exit vents in the bonnet will reduce airflow around critical areas such as the oil filter, sump, front diff and oil cooler. Raising the rear of the bonnet is just as bad the air will flow through the radiator then up across the top of the engine and out the back. It will not flow over the exhaust manifolds, turbo, oil cooler, sump, diff and gear box.

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even old SLR TORANAS have rear facing vents. well its a bonnet scoop really, but it faces backwards. need em for those fire breathing v8s but... not really.

a definitive answer on this topic would be great - on both what the ADR says, and about how effective/ineffective they are at keeping things cool. i figure if your cruising along slowly or parked in traffic a bit a rearward vent after the radiator would help, but if you are constantly hammering along at warp, maybe a fwd facing one, like the mighty rex has for its lil IC.

Was just told by a mate that it was proven that at speed air actually came out of the WRX scoop. There was a lot of air coming into the engine bay through tthe front of the car, creating positive pressure under the bonnet and had no where to go but out the scoop.................. dunno if it is true, but sounds plausable!

Plus wrx scoops are gay, I have seen them fitted on everything from a wr-excell to a stock corrolla.

Personally I would never get a forward facing scoop ever, but that is just me :P

well im not exactly going to be circuit racing and blowing hoses off my car so i have no qualms about throwing a bonnet on with a rearward facing scoop.

if the scoop sits after the radiator, before the front of the head, the only stuff that would come out is radiator fluid - which is not going to be much different than using your wiper washers as far as visibility goes. soon as i can GET one, im painting it, its on like donkey kong.

and Ska, i agree totally. seen one on an 89 laser. top that - should be a new thread - "crap we've seen wrx scoops on"

maybe its just the wording, but that made no sense to me whatsoever.

if the vent sits just after the radiator, the only fluid that could come out is from the radiator, which would be steam anyway (if its hot enough to build up pressure to blow of a pipe) which wouldnt be any more hazardous than wiper fluid, is my argument.

wow. cool. yet ANOTHER grey area. next time i get pulled over ill have to ask a cop. clear it up once and for all.

Asking a cop would probably prove to be the most unlikely, most unreliable way to figure out its legality.

The problem with that is that it'll be their interpretation of the rules (assuming they know them properly, and not all of them will) - so it might even depend on the mood that the particular cop is in on the day!

But regardless, here's hoping and best of luck getting a straight answer. Who knows, it might get us closer to an answer.

Nick T.

was in DMD image the other day to organise my kit and hit them up for details on a bonnet. They dont do stag bonnets, but can do me a fast and furious looking vented one for the paltry sum of 1500. they need to get one and make a mould off it. fantastic.

Don said if it were for more than one car, say two three or four, it would be considerably less. but i wouldnt want so many stags to have the same vented bonnet people will think its as standard as airbags.

thought about modifying my existing bonnet... dont know how fiberglass and metal would mix with that heat under it though. and suggestions or ideas or experiences or alternatives?

oh and dmd didnt have a WRX in site, let alone a scoop. love it. nissan central. few tricked out hondas...

<_< and terminal - your clear indicators go alright too...

Edited by qikstagea

lol i gave u a definitive answer - you cant have aftermarket rearward facing vents - well they can be rearward facing but CANT HAVE AN OPENING if they face backwards (only for looks is ok).

Here ya go:

An air scoop fitted to the bonnet of a vehicle must not intrude into the line of sight. An air scoop must not have an unobstructed rearward facing opening (an incident such as the bursting of a radiator hose could result in the windscreen becoming completely obscured). The maximum air scoop protection should not exceed 60 mm

Ive got a copy of the bit from the ADRs and licensing technical guidelines that says it. Even with front facing vents there's a load of guidelines and restrictions. Heres the scan of the front facing vent requirements too:

ScoopOpeningSize.jpg

And line of sight in relation to vents:

ScoopLineOfSight.jpg

so that covers scoops sitting OUT of the bonnet, but not vents that are cut into the bonnet. you read everything in this thread? doesnt seem too difinitive. what does "unobscured" entail> so if its a vent with mesh, its okay? see what i mean? and then theres the herrod rearward vent, among others. there are obviously ways around it, brazen.

dont be so quick to bend over for the government, champ. if you can register a car with a quad supercharged 26 litre engine (that, by the way, has a rearward facing scoop), im sure you can manage a vent in your bonnet.

so that covers scoops sitting OUT of the bonnet, but not vents that are cut into the bonnet. you read everything in this thread? doesnt seem too difinitive. what does "unobscured" entail> so if its a vent with mesh, its okay? see what i mean? and then theres the herrod rearward vent, among others. there are obviously ways around it, brazen.

dont be so quick to bend over for the government, champ. if you can register a car with a quad supercharged 26 litre engine (that, by the way, has a rearward facing scoop), im sure you can manage a vent in your bonnet.

oh dear... "unobstructed" means it cant get through (any liquid escape) - so mesh doesnt apply - pretty straight forward that one. The OUT of the bonet is just showing you max heights etc for line of sight... it still applies for vents INTO the bonnet - cant face rearward. You'll also note I said "aftermarket" - some pre-new-car-handover ADR approvals have been given (eg Herrod). So no I dont see what u mean - pretty straight forward to me after spending ages down the Technical Division reading through the ADRs and other guideliens with the Technical Manager over here in WA.... and yeah - as said in previous threads - maybe different over east - but normally things are MORE restrictive over there thna here in teh West. Its all just whether you'll get picked up though as to taking the risk - up to you - same thing with replacement front and rear bumpers - not allowed technically (can only have lip spoilers) - but peopel sell full front and rear bumpers for lancers and all sorts of shit - technically illegal - but hey never seen a lancer yellowed for the ricey bumpers though.

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