Cutting rear bumper for better aerodynamics?

[Black R]

I've been thinking about improving the aerodynamics of my s13, and am somewhat familiar with the fundamentals.

That being said, very little comes up via google search when looking for actual aerodynamic rear bumper s13 / 240sx threads or pics.

I did happen upon this blog with a s13 that has done what I'm thinking with the rear bumper:

https://thenaritadogfight.com/2015/0...-model-silvia/

Before I do this, are there any other concerns, etc?

I know a diffuser underneath is complimentary, and that's the next step.

[Sleepy_Steve]

http://www.stance-usa.com/main/wp-co.../DSG240rs2.jpg

http://image.automotive.com/f/images..._left_view.jpg

I think maybe closer to what Bill at Dentsport did is more effective than what you linked. Then a diffuser with vertical stakes later on.

[Def]

The stock gas tank gets in the way of anything really crazy. With it in there, you are limited to starting the diffuser (slowly) at the rear axle line, then making it a bit more aggressive towards the end. Put a gurney flap on the top to help prevent separation due to the increasing divergence angle.

Pretty simple though, not much geometry to get crazy with.

[Black R]

Thanks guys!

I'm not opposed to a fuel cell in the future, but this is a good start.

[gills]

What is the purpose of those huge inlets on the rear quarter window panels in those links? They look a little excessive.

[Colorado S14]

If I remember right he is running a rear radiator and coolers and they are fed via those ducts.

[240sxTTC]

If I remember right he is running a rear radiator and coolers and they are fed via those ducts.

Correct