Bonnet vents / Scoops

RIP57L

We all know our engine bay is as hot as fuck after a good drive - and heat is the enemy of turbo's, but has anyone actually thought about ways to get that hot air out?

Im thinking of cutting two vents into the bonnet and covering with silver mesh so that when the car is moving, the vacuum effect will suck the hot air out from the engine bay.. I think one major design flaw with the MPS is the cars lack of ability to dissipate heat..

Would anyone actually know a good location to cut two vents in the bonnet?

MattMPS3

DONT DO IT, bonnet vents are a precision item with plenty of R&D behind them, just hacking two holes in your bonnet can reduce airflow where its needed, there is a reason for the undertray and other deflectors & vents on this car.
I did read a report once, cant remember where, but a magazine threw a whole lot of temp sensors in the engine bay of a car, and tried several vent configurations, most of them resulted in hotter temps in critical areas, and higher coolant temps, with only a few actually improving the overall cooling. This was the same article that proved how ineffective the WRX scoop was, which probably explains why it has now been relocated.

Looking at our cars layout it appears to divert the available air around the engine and then onto the turbocharger, if you cut the holes, the air will not pressurise and flow through the engine bay, instead the air will just go straight out through the vents.
The enigne bay temps really arent too bad as far as turbo cars go, as long as you are moving the car is fairly cool, a good experiment is go for a hard fang, really work the turbo, park the car (leave it idling), pop the bonnet and touch the top of the IC, not too bad, close the bonnet and leave the car idling for about 5 mins, then touch the IC again, it hurts.

And besides, shouldnt you be driving an excel if you want to cut holes in your bonnet

Derek88

Just take the hood off. Extra air, weight reduction, and you can go back to stock anytime you want.

RIP57L

^^ LOL I wish hehe..

The funny thing is our engine bay doesnt look like it receives much cool air from the outsie apart from the ram style grille.

Doc

youd be surprised.. keep in mind Bernoulli's theory.. higher velocity lower pressure.. you can actually make a reverse flowing 'air scoop' and totally mess with your airflow dynamics for the engine bay cooling.. i would just leave it be