Have sketched these up, but not sure if I like them. What does everyone thinks or any tips for improvement? Is there enough 'meat' left around the bonnet catch?
Description
Description
I need to add some bonnet vents to let some of the air out from the engine what.
Have sketched these up, but not sure if I like them. What does everyone thinks or any tips for improvement? Is there enough 'meat' left
around the bonnet catch?
Description
Description
Looks like an ST185 bonnet vent?
I have put closable vents in the tunnel, may as well use some of that heat to keep me bits warm. Also louvres in the bonnet and small blocks at the rear edge of the bonnet leaving a gap for heat to escape.
i cut some in mine just like you have shown there, in the end nothing i did kept the oil and coolant temps under control untill i fitted a decent
alloy rad in place of the standard polo one.
it works so well now that on cooler trackdays i have to tape up the oil cooler, yesterday at croft all but the top inch of the oil cooler was taped
up(which obviously blocks up a fair bit of the rad as well).
If you're not sure, cut the vent shapes out of card or paper, and blue tack them on to the bonnet. Leave 'em for a few days and see if you
like them, if not, try a different arrangement or different shapes. I went through a load of designs before settling on the one I preferred:
It's quite complicated getting the shapes lined up right on a compound curve like the bonnet so it's worth the time, you might find that
something jumps out at you after a while.
Bigfoot's look great IMO - fit the car perfectly. But it may differ on yours, I tried that design on mine and it didn't look right to me.
quote:
Originally posted by benchmark51
I have put closable vents in the tunnel, may as well use some of that heat to keep me bits warm. Also louvres in the bonnet and small blocks at the rear edge of the bonnet leaving a gap for heat to escape.
This is what we did
Bonnet Vents both sides
Nose cone, side panel and rear of bonnet vents.
Vents
When i did a few on my car, i read up on (google) where is best to put them and why. While stationary most will let heat out but on the move any that
aren't in the right place could actually make things worse because the air flow can be going in rather than out! (high pressure zone).
Wool and sellotape is your friend 
Ian
quote:
Is there enough 'meat' left around the bonnet catch?
Hi, my bonnet is like that in the original post. The problem is if there is no duct behind it the air will more than likely be going in and adding to
your problem. I can feel the warm pour out when stationary but I need to either add some lips on the outer leading edges to 'bump' the
outside air over the holes to then pull the hot air out from inside the bonnet or add a back panel/duct behind it to stop air going in but letting it
out.
When I originally positioned my design I was concerned about rain water getting in when left outside so didn't add any to the top of the bonnet.
Round holes are much easier to cut in, it took me a good day to cut those shapes neatly into the side of my bonnet.
Here is a three part article on undertrays, spoilers and bonnet vents you may find interesting before you go start cutting your bonnet.
Part 1
Part 2
Part 3
