Thread: Bonnet scoop on RRC

Honestly this thread is pointless there is allready one on this very subject as mentioned above that covers all this and more...i wont be posting on this thread in future.

Will a bonnet scoop reduce heat in the engine bay?

Will a bonnet scoop reduce heat in the engine bay?

Hi Blackrangie

I appreciate you advising me of the post on disco 1 forum.

I started the post as I drive a RRC and have had this heat from transmission since I purchased her in early 2016 and refer my post in this classic section.

I don't drive a Disco so don't visit that forum page on this site ( no disrespect to Disco owners) and was non the wiser of its existence.

My 2cents worth the biggest problem with responses to posts is that you cannot tell the tone or the feelings you get compared with direct conversation with someone.

For myself ...in emails where I endeavour to keep them short they may come over terse or in a manner that may be taken the wrong way when I've reread them ...just ask my boss

That's why imogies (think that's the correct term) was invented to assist with this.

Your choice to make any further post but will keep an eye on Disco 1 forum page for updates.

Shane - I do remember you mentioning that matting for heat ...and appreciate you input in posts.

Cheers

Baggy

Hi RaZzor,

I do agree the scoop of Blackrangie does look good on the Disco and on the Rangie bonnet if it was just for cosmetic purposes with no holes in your bonnet.

Where we all agree to disagree is if it will do the intended job without creating further issues and the jurys out on both sides of that fence.

If you cut a hole into your bonnet you raise a valid point on water egress into your engine bay be it by rain or by a water crossing and how you would deal with that.

For me the GU scoop was the choice as it's not too large and I've kept the hole into my bonnet as minimal as possible to avoid pressurization of the engine bay which is the hot issue (excuse the pun) on this post

I've had similar results to Tombie ... Although non scientific but happy with results so far.

I'm hoping water egress will not be an issue but will have to wait till winter for that test and deal with it then


Cheers

Baggy

Hi all, an add popped up on Facebook this morning- a guy on Geelong selling his supercharged 350 chev, currently in a RRC... Notice the interesting multiple vents...IMG_2658.jpg

Nice looking Rangie.

So the vent at the rear would let hot air out and rain in. The venting of the hot air would cause a low pressure area and more air would be sucked through the radiator.

A forward facing scoop would have forced air and rain into the rear bulkhead area. That would raise the air pressure near the bulkhead and reduce flow through the radiator.
Is that right?

Originally Posted by DiscoMick

Nice looking Rangie.

So the vent at the rear would let hot air out and rain in. The venting of the hot air would cause a low pressure area and more air would be sucked through the radiator.

A forward facing scoop would have forced air and rain into the rear bulkhead area. That would raise the air pressure near the bulkhead and reduce flow through the radiator.
Is that right?

No. A reverse bonnet air scoop has it's opening in an area of higher pressure not lower pressure. You need to do the fluid modelling to determine if what you say is correct or not.

Before you put holes in the bonnet, you need to work out what you are trying to achieve. Some people put a forward bonnet scoop in their bonnet to reduce engine bay temperature. Some do this because they want air flow through an intercooler. Some do this because they want an increase in power. There is power loss because the carburettors have to suck harder and power loss from the less dense hot air. By adding a cold air intake above the radiator of my Commodore, the motor gained an extra 3kW.

Reducing engine bay temperature and increasing air flow through the radiator is not necessarily the same thing.
I have posted up a picture of a P38 with a forward bonnet air scoop. The owner had issues with the engine running hot. Installing the air scoop reduced the engine bay temperature and solved his hot engine problems.

Originally Posted by grey_ghost

Hi all, an add popped up on Facebook this morning- a guy on Geelong selling his supercharged 350 chev, currently in a RRC... Notice the interesting multiple vents...IMG_2658.jpg

That looks like it's had a huge amount of time and effort gone into it. I think the bulge .... is a bulge not a scoop that opens it to the engine bay ? (to clear the supercharger ? ). The side vents should work really well to clear underbonnet air in traffic I imagine ... I doubt they would effect cooling at speed ( I really don't know, but I don't think that is a high pressure area there ... if it's low pressure, it's only going to do good things ... ie: help exhaust hot air from the underbonnet area at any speed and under all conditions).

seeya
Shane L.

Not all scopes are doing the same thing

are you trying to ram air in the intake, cool an intercooler, or remove hot air from the engine bay.

Pick that first, then go to your craft shop, buy some wool and some sticky tape and do some wool pile testing at various speeds before you even think about adding or cutting

unless its just for the cool/**** factor, then have at it.

Dont discount the engineers that designed these vehicles in the first place.

Who really wants a forward facing scoop on a 4x4??