Bonnet Scoop orientation: forwards or backwards?

[gq351]

haha its acually a BB chev, i guess my user name gave it away LOL
it used to be a 351 ford!!
the only reason i put on this scoop was to clear the air-cleaner but it does run abit cooler as all the hot air has got somewhere to get out...
scoop is off a VK SS

[simcoe]

before you do anything, space the rear of the bonnet up about half an inch.
that way you will know if removing teh air from the enginebay will help you much.

My bet is that it will reduce temps dramatically.
BUT.

if you every blow something in your enginebay, its going to be all over your windscreen. Even just a heater hose will mean you have bugger all visibility.

cheers,

Jes

been reading this thread with great interest as i have just fitted a inj 5.0l to my GU(updated write up later) and although mine doesnt get hot one litte bit even with towing a trailer on beach coming home from camping i do notice that when i pull up after driving that the heat coming from the side's of the bonnet is very noticeable, more so then my old 4.5 used to be!
Now as Jesse has said above regarding spacing the bonnet by 10-15 odd mm will reduce engine bay temps i would have to aggree(though not tested) if i had a bigger gap the heat has a better chance of escaping!!
the bloke at work who's got a commy v6 in his old school 4 runner has also done the same thing and reckoned it stopped his from over heating!

im going to giv it a go just to see if things run cooler!

cheers
aaron

[coxy321]

Not too sure if its been mentioned in this particular thread, but bonnet spacing can turn your bonnet into a pretty handy guillotine if you happen to have a front-on stack.

99% sure it isn't legal in any state either.

Just my 2c

[bluemq]

before you do anything, space the rear of the bonnet up about half an inch.
that way you will know if removing teh air from the enginebay will help you much.

My bet is that it will reduce temps dramatically.
BUT.

if you every blow something in your enginebay, its going to be all over your windscreen. Even just a heater hose will mean you have bugger all visibility.

cheers,

Jes

Jap drifters do this because they need the extra bonnet clearance when fitting RB20/25/26/30 to an s13 (Silvia/180sx).

They do it because its the cheapest way to get clearance they need.

It actually makes the engine cooling worse. To fix that, they end up fitting oversized radiators and massive thermo fans.

I would steer clear of spacing the bonnet for this reason.