What s the gain on 1/4 with a flat bottom?
Which material and thickness?

 

Aluminium should be the lightest, 1 or 2mm?

 

Any feedbacks?

 

My opinion is that all it may do is create stability at high mph however I haven't done a flat bottom so I am not 100% sure.

I personally don't think it does anything to make you go any faster really, adding an entire flat bottom will just make the car heavier.

That is is just my opinion.

 

I'd use Alumalite over sheet aluminum. That's basically corugated aluminum that is extremely light with extremely high rigidity.

 

Gringotegra probably has the most experience with this, he has a bunch of threads.

 

There are definite aerodynamic improvements with a flat undertray. For road racing in a class that allows it, it is a no-brainer. For drag racing, its hard to say if it would be worth the weight.

Assuming youre referring to the car in your sig, trapping at 165mph, I think it would be worth trying. A good place to start would be making a pan for under the engine bay. That is going to be the largest area of disturbed air on these chassis, and wouldnt add too much weight.

 

Fiber cardboard and speed tape would provide clear answer

 

This but there is also a carbon/kevlar version that is extremely rigid and even lighter! Though it is around $600 for a 4x8' sheet of it.

 

I used 3 layers of pre-peg carbon, basically just cut it out to the desired shape, then baked it and installed it.

 

ABS sheet?
ABS General Purpose Sheet- Textured Haircell Finish

 

Thks guys

 

ABS is heavy. You would be better off using Alumalite or wood.