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

Looked into this and there's probably a thread running in the RRC section along similar lines. I was going to conduct an experiment to find the low and high pressure areas around the bonnet and guards, but my RRC has other issues so never got any further. As Rick said, the bonnet area near the windsceen is a high pressure area and the biggest issue on the RRC or Early Disco's is getting the hot air out from under the bonnet. There isn't a whole lot of room for it to get out underneath - the best bet seemed to be vents in each side - I was going to chase up some D3 side vents and try this, but again, never got around to it.

I'm about to drag the RRC out again and do some work on it, and this is on the list but doubtful I'll have anything to report for some months.

i expect your report to be on my desk by the end of the week.

You going to sit there and wait for it?

If so, I want a picture of your beard growing long and grey while you wait...

There is a fellow on here who had a P38 (with a LS1 I think) who put a forward bonnet air scoop on it to cool the engine bay down.
He said it worked.

I have a photo somewhere.

i have been thinking for a while to put something like this on my bonnet. wanted to get a spare bonnet from wreckers and test first, after doing the string test on it.

basically wanted to put one over the intercooler pipes, turbo area and one on the opposite side just for symmetry. the aim for me was to get cool air from the front to go past the intercooler pipes that go near turbo and exhaust and exit through the vent. need to do more research though as it's possible that it could pull cool air from somewhere needed and take it elsewhere (but i doubt that, there should be a fair bit of cool air coming from everywhere and it would reduce overall under bonnet heat in my opinion). I was going to put a heat shield on the exhaust side of the pipes and even looking at putting fins to act as a heat sink. then i wanted to also put ceramic coating on exhaust and inlet manifolds. basically all to stop heat transfer and cool the inlet air as much as possible.

probably a lot of work for something which will make little difference, but nothing very expensive, nor difficult either.

jaguar-f-type-convertible-luxury-sports-car-bonnet-vents-south-africa-GDTGDX.jpglouvre.jpg

Originally Posted by Mick_Marsh

There is a fellow on here who had a P38 (with a LS1 I think) who put a forward bonnet air scoop on it to cool the engine bay down.
He said it worked.

I have a photo somewhere.

a forward one?? well that throws a spanner in the works

Originally Posted by Fausto79

i have been thinking for a while to put something like this on my bonnet. wanted to get a spare bonnet from wreckers and test first, after doing the string test on it.

basically wanted to put one over the intercooler pipes, turbo area and one on the opposite side just for symmetry. the aim for me was to get cool air from the front to go past the intercooler pipes that go near turbo and exhaust and exit through the vent. need to do more research though as it's possible that it could pull cool air from somewhere needed and take it elsewhere (but i doubt that, there should be a fair bit of cool air coming from everywhere and it would reduce overall under bonnet heat in my opinion). I was going to put a heat shield on the exhaust side of the pipes and even looking at putting fins to act as a heat sink. then i wanted to also put ceramic coating on exhaust and inlet manifolds. basically all to stop heat transfer and cool the inlet air as much as possible.

probably a lot of work for something which will make little difference, but nothing very expensive, nor difficult either.

jaguar-f-type-convertible-luxury-sports-car-bonnet-vents-south-africa-GDTGDX.jpglouvre.jpg

Both of those types look really good, both would require some metal work more than just cutting the hole and dropping the vent in.

Originally Posted by Ace

Both of those types look really good, both would require some metal work more than just cutting the hole and dropping the vent in.

there was a website i found on net that sold black plastic louvres of different sizes. basically just had to cut holes in bonnet and they had a special lip that just clipped in. had some kind of seal to go around and a template which came with it for the hole. then it was just a matter of clipping it in. nothing else to it. i forget what the company was called, but theres a few around. i dont think there would be any metal work involved apart from cutting hole. could just rivet a metal louvre on top of the bonnet on a pre cut hole which didnt necessarily have to be the same shape.