Thread: Will a bonnet scoop reduce heat in the engine bay?

Originally Posted by blackrangie

What are peoples thoughts on increasing the high pressure in that area just in front of the firewall & under the bonnet & thereby helping the venturi effect.

So with the 79series bonnet scoops, the holes in the bonnet should be to the rear and both sides of engine, thus fresh air in the rear of bonnet and down each side of engine and out, and in a way maybe even sucking more air through rad in the process or making it easier for air to get out of engine bay..similar to ram effect of snorkel.

With engine off and maybe at idle will no doubt vent out the scoop.

See air in orange in pic attached

You would be better turning the scoop around so it causes a low pressure area under the windscreen and draws air out from under the bonnet

Remember, fast flowing air past an opening will suck hot air out...just like a spray gun

All you are going to do with that scoop facing forward is pressurise the engine bay, stopping airflow thru the radiator

Originally Posted by Morry948

The problem with a bonnet scoop is it will pressurise the engine bay. You will get plenty of air flow thru the scoop and out the engine bay, but will stop any airflow thru the radiatorYou want as much air as possible going thru the radiator, not thru the engine bay per sayYou need to open up the area behind the rad to allow the air to flow, not add more air to it

Did you look at the post above yours at all?

Originally Posted by Morry948

You would be better turning the scoop around so it causes a low pressure area under the windscreen and draws air out from under the bonnet

Remember, fast flowing air past an opening will suck hot air out...just like a spray gun

All you are going to do with that scoop facing forward is pressurise the engine bay, stopping airflow thru the radiator

Again did you see the post above at all addressing this

Makes sense

Sorry...an overtired me..

I can see how your trying to move the air. Use velocity to create a low pressure area past the exhaust/turbo which should drag the hot air out with it and exit it out under the passenger door/front wheel

Originally Posted by Morry948

Makes sense

Sorry...an overtired me..

I can see how your trying to move the air. Use velocity to create a low pressure area past the exhaust/turbo which should drag the hot air out with it and exit it out under the passenger door/front wheel

Spot on, thats the theory

I reckon one of those XA bonnet scoops ( the ones that sit IN the bonnet ) would work

You want some velocity, not volume

Bit like a brake duct

the speed of the air past the bonnet determines what type of scoop you would want, i reckon. Need cooling on the Hwy - easy to utilise the massive airflow - slow bush work is a different story - then you need something to evacuate the hot air rather than some forward facing scoop that will just ingest more dust and rain and water at river crossings

These either side of the L322 would help engine bay ventilation. But I think it’s a minimum and would like more.