Hood vent orientation?

[JulianEdgar]

Originally Posted by eagle

the fiesta in nearly all rallycross/wrc/s2000 versions uses the same spot for the hood heat extractors along with some metal (?) around the inside half Im guessing in order to create vortices for even more heat extraction (??)



anyway, since EVERYONE in the motorsport industry uses the same spot I am pretty sure its measured and proven correct, however water ingestion in a daily driver would be a pitta since in both places there are sensitive parts like ecu loom , battery etc so a proper water trap must be used somehow

As Vman455 suggested, for a road car, taking lessons straight from motorsport is fraught with danger. Looking at those pics, I'd suggest they expect lots of yaw (ie airflow not coming directly from the front) - which may well be the case in rallying!

With this sideways airflow, the little deflectors would decrease the pressure downstream, so aiding flow out of the holes. I can't see you driving much like that on the road...

I'd probably go with this if you like the idea of the side vents:

[eagle]

Originally Posted by JulianEdgar

As Vman455 suggested, for a road car, taking lessons straight from motorsport is fraught with danger. Looking at those pics, I'd suggest they expect lots of yaw (ie airflow not coming directly from the front) - which may well be the case in rallying!

With this sideways airflow, the little deflectors would decrease the pressure downstream, so aiding flow out of the holes. I can't see you driving much like that on the road...

I'd probably go with this if you like the idea of the side vents:

Ok I kinda understand what you just said

the best and most popular fiesta vent is this "focus rs styled" vent



pretty much everyone uses this but have different approach so each one cuts and places the vents where they want on the bonnet (there isnt any proven point yet)

how could I use a magnehelic gauge on the bonnet and what should I look for?

[JulianEdgar]

Originally Posted by eagle

how could I use a magnehelic gauge on the bonnet and what should I look for?

I think from looking on my YouTube channel, you've bought one of my aero books, no? It should all be explained there, but basically you run a hose to each area you're interested in (ie above and below the bonnet) and find the locations with the biggest difference (high under the bonnet and low on top). It's very interesting doing the testing - and don't forget to do it on a windy day too (because the results will be slightly different). Make sure you select a gauge with the right range - should be in the book.

[eagle]

Originally Posted by JulianEdgar

I think from looking on my YouTube channel, you've bought one of my aero books, no?

I am waiting for it

current post office service speed:

ok, will post my findings after the test!

[19bonestock88]

Originally Posted by JulianEdgar

As Vman455 suggested, for a road car, taking lessons straight from motorsport is fraught with danger. Looking at those pics, I'd suggest they expect lots of yaw (ie airflow not coming directly from the front) - which may well be the case in rallying!

With this sideways airflow, the little deflectors would decrease the pressure downstream, so aiding flow out of the holes. I can't see you driving much like that on the road...

I'd probably go with this if you like the idea of the side vents:

I was kinda leaning toward that vent personally, being that it halfway mimics what others have done with success. The PCM is under the vent behind the drivers side headlight, but I figure I can make a rain deflector out of some flashing or coroplast or something to keep rain from going directly into the PCM wiring, the rest of the area under the vent is fairly safe

[2000mc]

Have you pulled down the insulation / fire blanket under the hood to see if there is bracing that might make installation in some locations prohibitive?

[eagle]

Originally Posted by 2000mc

Have you pulled down the insulation / fire blanket under the hood to see if there is bracing that might make installation in some locations prohibitive?

Are you replying to me or "19bonestock88" ?

[2000mc]

Originally Posted by eagle

Are you replying to me or "19bonestock88" ?

19bonestock88, however, I guess it applies to anyone trying to decide where to mount them. From the inside the hood may not look to be such a blank slate and there could be limited placement options available without compromising the strength of the hood, or creating considerably more work.

[19bonestock88]

From pictures in the Redline group (FB), and from pulling off the insulation I know that most of the vent mounting places would require some cutting and/or drilling of the hood bracing. I’m totally fine with that, given that I planned to gut the hood bracing anyway (just shy of removing it entirely) to save weight

[19bonestock88]

So I’ve started with the vent installation, and it’s been a huge undertaking. Having to cut out a lot of the bracing to make the vents work. The hood should still be fine, as it basically had most of a second skin underneath it, and it was much heavier than the sedan hood I had before. I replaced the prop rod with a pair of gas struts, partly because I had them with the hood before, and partly because I’m going to have to cut the prop rod hole out for the center vents. I ran out of reinforced cutting wheels, so further progress is either going to be painstakingly slow or I’m going to buy more wheels.