wanting to increase handing... under tray

[99eclipse420]

I saw a video for a ferrari awhile back ago, and it said that their new models have an under tray, which is a vent that is attached to under side frame and the way ferrari says it works is that as air passes through it, it pushes down on the car and in theory the faster you go the more grip you have. so i was thinking about welding sheet metal about an inch to an inch and a half from the frame to allow air to pass through. Any ideas on how i should go about this should I re rout the exhaust to go under it or just leave it alone and just shape the sheet metal around it. what do you guys think and how would you guys go about this.

 

[greengoblin]

I think there are a million other things you could do first and this is a waste of your time.

 

[snowborder714]

I would look into other means to increase handling before I'd suggest to look into this. The bolt on parts will be much easier than an undertray will, and will probably net you a better feel for handling.

Parts to look into:
-aftermarket shocks/springs or a coilover system
-sway bars
-wider wheels/tires


If you want to learn more about them, google "undertray" or "flat bottom aerodynamics".

 

[Arthris]

The Ferrari is a pure sports car. They will go faster than you will probably ever need to on the street. And they are made to have that. No-one knows what will happen if you did it. For you know it could severely hinder the performance of ## car.

 

[gusu]

I don't know about how Ferrari is getting air to it but the answer to build up of lift under the car from using ram air was one of these trays. From what I have seen all of the trays have used something from the hood to pull the air down.

What does not make sense to me is all of the new Ferraris I have seen are mid engine. So I'm not sure how this would be set up aerodynamically.

 

[snowborder714]

An undertray is used to keep air from bouncing around the underside of the car and reduce drag, and will also create a low pressure zone which will help to suck the car to the road. However, an undertray alone won't work as well as you think, and would need to be aided by a front air splitter and probably some side skirts (obviously from an aerodynamic design).

 

[nitroazz]

The best would be to see this installed and have it flip up and around like the rx7 video on the salt flats.

Because that could happen. Use this under your car, hit a certain speed and the force of the air travelling under the car will be great enough to lift the car off the ground.

Good luck tho, it is a thought in the right direction but there are so many other modifications that can be accomplished before this would ever be necessary.

 

[Billiam]

This would be a great idea IF you had much more suspension mods. Unless your trying to go into Time Attack or something I wouldn't do it, but may be worth something to look into in the future. Also there is a bit more that is going on with the Ferrari's undertray than just mounting a sheet of metal or carbon fiber. Its most likely going to be extra weight slowing the car down with out any benafits. There is some threads in here showing what people made for increased downforce but these are roadcorse guys who have done a bunch of suspension mods and need that extra cornering speed.

The best would be to see this installed and have it flip up and around like the rx7 video on the salt flats.

Because that could happen. Use this under your car, hit a certain speed and the force of the air travelling under the car will be great enough to lift the car off the ground.

Good luck tho, it is a thought in the right direction but there are so many other modifications that can be accomplished before this would ever be necessary.

Not when its done right, the key thing is the get the air passing under the car to accelerate creating downforce so that it would be more planted on the ground at higher speeds. Also lift is achieved by the air slowing down undernieth the vehicle so your theory is false. Plains wings are designed to have the air above it accelerate while below it will be going much slower causing lift.

 

[spyderdrifter]

Obviously, the obvious has been said as to why you don't need to concider an undertray. However, if you do decide to fabricate it, don't make it a weld on assembly. If you weld it to your frame, you'll run into issues removing your exhaust in the future. Fab it up to be removable and keep your exhaust inside the undertray so it doesn't take away from the aerodynamic properties of the tray. As it's been stated, the undertrays on high end exotics suck the car to the road. Leaving your exhaust exposed will diminish this aspect of performance. I think you should build it, but only if you're planning to use it for racing, any other reason will only be a waste of time and add unneeded weight. (And why do you need it on a N/T DSM?)

 

[eclipsh]

I've thought about undertrays in the past for aero but everyone here is missing out on another benefit: increased rigidity in the front end. If an under tray were made properly and bolted to the k-member at key points it would really help stiffen up the front end AND help with aero. It'd be a twofer. It would also take a lot of careful design work and fabrication to make it happen.

Side thought: I'm not so sure I want to trap the air around my hot exhaust inside the engine bay.

Lastly, it would really need to be done along with a well vented hood since the radiator pushes all that heat out under the car right now and (last I knew) wheel wells are high pressure zones so the hot air wouldn't escape that way very effectively if at all.

I won't jump on the band wagon abusing the OP since he's already been beaten to death (not completely without reason, mind).