What are your opinions? The proposal seems promising. I've observed that the steering becomes less precise at higher speeds. Considering the common issues with engine and diff cooling, I'm curious whether this solution would effectively address these concerns.
GR Yaris WRC bonnet vents to reduce heat issues?
- Thread starter 6mt
- Start date
What are your opinions? The proposal seems promising. I've observed that the steering becomes less precise at higher speeds. Considering the common issues with engine and diff cooling, I'm curious whether this solution would effectively address these concerns.
sixtentouge
Totally Hooked
- Aug 28, 2023
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He's correct about heat in the engine room. The more you can increase the ∆P across the radiator, the better the cooling. Hood vents, when done properly will evacuate air from the engine room, less goes down the tunnel, etc.
He's also correct about the implications of hitting a pedestrian. The factory hood is engineered to minimize injury in a pedestrian impact. A "stiffer" carbon hood is built with weight savings and cool looks in mind. Also, low volume production, it's cheaper to build a carbon hood than it is an aluminum hood, due to the tooling requirements. Outside of the factory GRMN hood, I doubt you can find a hood that's been tested to meet pedestrian impact requirements.
The GRMN hood also comes with detachable covers on the inside for rain water protection.
As far as the effect on aero, that's all over the place. If I were going to design hood vents, I would probably start by copying an engineered product, like the GRMN hood.
Michael Knight
Totally Hooked
I like the idea but exposing ecu and also AUX belt for external water pour doesn't feel really good. Maybe I'm just overthinking. but have been considering the vents for a while now.
Agreed. I wouldn‘t do that on a Daily…
One of the reason, Subaru has it‘s side bonnet vents closed from underneath, so no water can get in.
Greenthumb
Totally Hooked
I remember from my Evo days there was a trend to raise the hood. Do you still do that today?
Helmut Eder
Devoted member
Pogea Racing GmbH which is Located in Friedrichshafen, Germany has a carbon hood with vents that is TÜV tested & meets the pedestrian impact requirements.
You can also leave the car under the open sky while it rains, the hood is designed to let the water flow away safely, without damaging anything in the engine bay.
With this hood, the engine bay is around 44°C cooler vs. stock.
Michael Knight
Totally Hooked
Is there a direct link? Searched but didnt find any
Like here?
I opened up the bonnet a bit (remove corner foam and remove cover inside bonnet for high strut towers), and found the engine bay gasses got sucked into the interior ventilation. But am now considering to open up the rubber strip towards the left side (seen in driving direction) to have some additional venting, before cutting the bonnet or splashing big €€€€ on carbon bonnets...
- Thread starter
- #10
The Pogea Racing bonnet looks interesting indeed. I couldn’t find any links, but I dug up a YouTube short:
There's no product page for it on their website, hence why you did not find anything.
Watch the yt short that was posted from @6mt to get a better look at it.
I got informed it existed because I talked with Mr. Pogea himself on the phone a couple of times because I would like to get their "MONSTERexhaust" fitted to my GR Yaris next year.
Sekred
Totally Hooked
- Dec 18, 2021
- 473
- 604
I wondered what the purpose of those corner pieces of foam was and now I know. Make sense too regarding the ventilation intake.
Michael Knight
Totally Hooked
at least it deadens noise to some extent. maybe fumes too.
sixtentouge
Totally Hooked
- Aug 28, 2023
- 206
- 837
The instructions that come with the GR Parts front strut tower bar say to remove the foam blocks. Which is weird, as the blocks are shaped to conform to the tower bar... I put them back in.
More details please
Short introduction to myself, my name is Chris, 40 years old, Dr. in mechanical engineering, since my childhood I build and fly RC planes and helicopters and do sailplaine-gliding, so I like aerodynamics 
I like the vents from speed engineering, but they don't have a spoiler in front, so the offset of the vent will become a turbulator and turbulent air wants to follow surfaces easier than laminar flow, so they want to curl in the vent.
That's the point I started in my christmas hollidays.
I have no 3D scanner so only foto, and ruler and so on and desiged them. Than I talked to the TÜV if this is possible to use on track.
He gave me some advides, radii and that I don't cut the main-frame, the big struts und the underside.
But, if necessary, I can cut the parts which are not so prominent/thick, this is more a subframe.
So I measured the distance from the outside to the end of the main-frame
My first attempt was to print the complete mesh, but the flow-area will be reduced, so I have now a 3 piece vent > Main-Vent, mesh, mesh-frame.
And for the rain, I designed a cover that can be screwed on with an outlet for a 10mm tube.
The will be produced in SLS PA12 with a 6,3x6,3x1mm stainless steal mesh
I like the vents from speed engineering, but they don't have a spoiler in front, so the offset of the vent will become a turbulator and turbulent air wants to follow surfaces easier than laminar flow, so they want to curl in the vent.
That's the point I started in my christmas hollidays.
I have no 3D scanner so only foto, and ruler and so on and desiged them. Than I talked to the TÜV if this is possible to use on track.
He gave me some advides, radii and that I don't cut the main-frame, the big struts und the underside.
But, if necessary, I can cut the parts which are not so prominent/thick, this is more a subframe.
So I measured the distance from the outside to the end of the main-frame
My first attempt was to print the complete mesh, but the flow-area will be reduced, so I have now a 3 piece vent > Main-Vent, mesh, mesh-frame.
And for the rain, I designed a cover that can be screwed on with an outlet for a 10mm tube.
The will be produced in SLS PA12 with a 6,3x6,3x1mm stainless steal mesh
Looks promising, I suppose some more finalising the design (no scan so maybe some curvature?) with test fitting and some field testing?Short introduction to myself, my name is Chris, 40 years old, Dr. in mechanical engineering, since my childhood I build and fly RC planes and helicopters and do sailplaine-gliding, so I like aerodynamics
I like the vents from speed engineering, but they don't have a spoiler in front, so the offset of the vent will become a turbulator and turbulent air wants to follow surfaces easier than laminar flow, so they want to curl in the vent.
That's the point I started in my christmas hollidays.
I have no 3D scanner so only foto, and ruler and so on and desiged them. Than I talked to the TÜV if this is possible to use on track.
He gave me some advides, radii and that I don't cut the main-frame, the big struts und the underside.
But, if necessary, I can cut the parts which are not so prominent/thick, this is more a subframe.
So I measured the distance from the outside to the end of the main-frame
My first attempt was to print the complete mesh, but the flow-area will be reduced, so I have now a 3 piece vent > Main-Vent, mesh, mesh-frame.
And for the rain, I designed a cover that can be screwed on with an outlet for a 10mm tube.
The will be produced in SLS PA12 with a 6,3x6,3x1mm stainless steal mesh
I print one with my FDM-printer to look if everthing is ok.
The area where it is glued on is not so much curved, so my idea is, that the Skifaflex-Glue will fill the gaps.
There is also a small groove for the glue under the lower surface of the main-part
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