carlsbad

anybody make rear rear diffusers for C5?, pics anyone?

Blue Blood

A couple have tried but they didn't look very good. Should turn up on a search.

jkz06

the ones I've seen look like tacky add ons. A lot of us paint the bottom portion of the bumper and it looks pretty good. Just a thought.

~Josh

If you want a diffuser to really work, you need to have it as part of a complete undertray that channels air from front to back with the diffuser section being the final part of the sequence.

Bolting on some plastic vanes to the back of your car is no better than a bandaid on a machete chop, and if someone doesn't care about the physics, then it's all about the rice...

Just saying.

~Josh

Another thing, if you really care about high speed aerodynamics, the C5z is inferior to the C5 coupe in that department.... so....

kerryt1

Nobody has made an acceptable one, functionally or cosmetically.

AU N EGL

Functional on a C6Z



C5 functional


Both would like like chit on a street car

Khaalathas

It is? How So?

~Josh

There have been several threads about this I think you can find in the Tech or General section.

Basically, the contour of the rear hatch on the Coupe is better at minimizing the turbulence as the air is washing off the back of the car. The FRC is at a disadvantage in comparison if you're talking about high triple digit speeds.

EBM_Z06

Here is what I have on my Z for a diffuser. It's made of carbon fiber. Not ment to be functial, just for the looks but I like it.

ZEE-OH-6

The stock C5 Coupe has a higher top end speed then the stock C5 Z06.

something like 175 mph v. 165 mph I think, I believe the air flow from the Coupe's rear glass has a lot to do with it ?

vant

Actually the aerodynamics of the rear window has almost nothing to do with the C5Z's top speed vs the coupe. The C5Z is limited by 5th gear @ 172mph.

Grimlock

It is gearing that is what causes the difference in top speed. Top speed in a Z06 is 171 MPH vs 175 MPH in a coupe. There might be a slight aerodynamic advantage to the coupe, but I can't really comment on it.

AU N EGL

magazine dribble

the Z06s hp and less wt give it the advantage.

Put the same hp, and reduce the coupes wt, well then we have a comparison

Grimlock

If this is the case, then why is the Z06 slower? If weight and power are all that matters...

I guess if we believe you, we might as well go for world speed records in a SUV or pick-up truck, since aerodynamics don't matter.

AU N EGL

aero does matter quite a bit.

and the Z is not slow, it is faster. But then again, I ( we) only get to the mid 150s on most race tracks long straights.

Aero matters so much that putting duct tape over the fog light / zo6 screens sees 3-4 mph more at redline 4th gear. Which means taking out a very popular CAI.

Grimlock

Totally agree. I used to race and modify race cars for a living. I've driven a car that can literally drive upside down at 150 MPH due to awesome aerodynamic design.

Wait a second. This makes ZERO sense. Gears and speed are linear. Making the car more slippery makes zero difference. If you are at 6,500 RPMs (same gears) then you will be going a set speed, aero makes zero difference unless you are power limited. Aero will help you hit redline more quickly, but it has nothing to do with speeds you are hitting in 3rd or 4th gears at redline.

z06801

I think that is what he means, the straights only so long so the car that would hit its top speed first would achieve the higher top speed on the straight. just like adding more angle to your wing will also effect your top speed

AU N EGL

That is what I thought too. Maybe those were just good days. But it was enough to constantly keep those fog light areas duct tapped shut.

Moto One

There's a reason why General Motors use or fastback over the FRC body for the C5Rs, the aerodynamics were better.

And you can get better speed through aerodynamics because there's less wheel slip with less drag at top speed. A Z can have up to 5% difference in wheel speed and true speed when running at max depending on the road/track surface.

Mark