Z06Fix

Looking seriously at doing the ZR1 front splitter and either the ZR1 rear spoiler or the Katech rear spoiler along with it. Are there any issues with doing the two at different stages? I would do the rear spoiler first.

Is the OEM rear ZR1 spoiler really enough to provide downforce? Or is something like the Katech the better option. This is a street car so I don't want a wing or something that just really stands out. I saw the Katech setup on Painrace's car at RA and I really liked it. My only issue is that it really stands out and catches people's attention. I like the low key look of the OEM ZR1 unit. But if it isn't enough to really do any good then I will look at other options.

I dont want to do the side skirts either way. Just not sold on the looks. Is either a one a better option for no side skirts?

Right now I'm planning on the Katech front ZR1 style splitter and the OEM ZR1 rear spoiler.

Would love to hear everyone's thoughts on the idea.

Thanks

Eric

BEZ06

Huh??????

The standard aero features of the C6 Z06 will take care of you up through at least 175 mph, and probably up to much more than that (I've only checked it to 175).

Considering you probably don't need much additional aero downforce until up in excess of triple digits, there's nothing you need other than what the stock car has for anything you can do with it on the street.

If this is a street car then my recommendation is to leave it alone.

If all you want is "looks" then do what ever you want - you aren't going to be going fast enough on the street to have any aero problems from what ever you put on the car to change it from its nice stock characteristics.

Bob

davidfarmer

I think the lower, longer ZR1 splitter can add some considerable improvement, although neither really add any downforce considering there is an airdam under the radiator creating pressure under the nose. The stock Z06 spoiler drags the ground at around 100mph, and again the airdam negates any attempt at creating downforce.

I think the GM rear would be a good balance for the ZR1 splitter, although I like the looks of the larger spoiler from Katech.

Short-Throw

Eric,

With respect to aero helping and not hindering you, these two mods go hand in hand. Without going into specific counts of downforce, if you look at the full length spoiler that GM came out with as an accessory (first on Ron Fellows Edition), that was the largest amount of downforce they could offer without the requirement of changing the front splitter. Adding a huge spoiler/wing will push the front end up at higher speeds without proper counter measures.


Mike

Katech_Zach

You don't need thoughts you need data. I recommend you read my upcoming aerodynamic report coming out next week.

95jersey

If the air dam creates an air pocket under the car, would a vented hood reduce that pressure? Aren't most GT cars (C6R) bottom breathers, but with an exit vent right in front of the engine coming out of the top of the hood?

If so, then to get true aero benefit, one would have to consider a vented hood along with the spoilers and splitter.

AU N EGL

GT front engine race cars are front breathers, not bottom breathers.

yes the extractor hood allows the air to flow though the front grill, though the radiator and out the extractor hood.

The bottom is flat and sealed off.

Remember 70% of a cars aero is from the flat bottom and rake of the car, not wings 20%, or spoilers 10%. IIRC

Low pressure under the car, and high pressue over the car, sucks the car into the ground, Bernoulli effect.

having spoilers and wings, yes they look cool, but doing nothing under the car is almost a waist of time.

Converting a C6Z to a front breather for the radiator and brake cooling ducts should not be that difficult. Then the lower front diffuser and longer front splitter could be added.









Red is high pressure

Blue is low pressure


Best aero is a proper rake to the car, and your alignment.

Mjolitor 68

The problem with doing ONLY the front splitter or ONLY a rear spoiler is aerodynamic balance

a spoiler will push the front end up causing lift and more understeer and less control

A splitter will cause more oversteer which will make the rear looser

So Ideally you want to do both simultaneously to maintain your cars balance

If you want real downforce in back but dont want a C6R style wing then the Breathless diffuser is excellent for that


As for the vented hood it has many advantages, its carbon so its lighter, provides more downforce as its covered w little spoilers, gets lots of heat out and I think it looks great

As for the stock Z body, its very aerodynamic but lacks downforce. Mine got squirrely in stock form at 130 entering the banks at Pocono

Now with all my aero gadgets its sticks to the track like a leach

Z06Fix

I remember both you and I asking Lou if it was a good idea to remove that airdam to reduce some front end lift. Did you ever try it?

Z06Fix

I'm looking forward to it. Your front splitter is a flat bottom piece isn't it? Seems like that combined with removing the factory airdam would be big improvment.

Z06Fix

Great info Tom. Being an engineering mind I like seeing data

davidfarmer

Lou said, and I agree (with no data to back it up) that the airdam improved fuel economy/reduces drag for GM. If I had the money for a ZR1 or similar splitter, I'd fabricate a flat panel to bridge the nose of the splitter to the airdam, and trim the airdam flush with the bottom of the panel/splitter.

95jersey

Here's another question. The C6Z actually has an open vent in the front for the radiator, vs. being a true bottom breather like a C5. The opening in the front is functional

Does that make things and different?

davidfarmer

In the C5, the air that did get trapped under the nose would flow up through the radiator....excess spills under or around. On the C6, the air under the car can only go under or around.

.....so, less air get under the nose, but all of it must spill around or under the car. C6Z should be better, but probably not much. Ideally the splitter is low enough that very little air goes under the car, and you eliminate the airdam so that said air doesn't stagnate under the nose.

Katech_Zach

It will push the rear down and maybe the front end up but not necessarily. Ask me how I know.

The stock car has a lot of lift in the front. Splitter only could help balance the car more. We didn't test splitter-only.

Katech_Zach

We tried it. It greatly reduced front lift. We suspect it may affect the function of the brake cooling ducts though. We didn't instrument them to test so do it at your own risk.

Katech_Zach

There is a version with and a version without the undertray. The undertray version is a huge improvement partly because it does necessitate removing the air dam.

95jersey

And after the owner has spent $5000+ on expensive splitters with trays and rear splitters, with wings and spoilers, and getting them painted and installed....a good allignment, set of $2500 coil-overs and sway bars will blow away the performance gained by all of these aero's put together (not directed against Katech of course, just a general perception)

From what I can truly ascertain, if you are rich and like an awesome looking Z with all the cool racing goodies aftermarket aero, and money is no object, go for it (we love to see them at the track, they do look cool)

If you are looking for mods that provide results on a STREET car at the track, save the $$$ for suspension, brake and engine mods. Don't get me wrong, I love the way the splitters and spoilers look, but I would do them with ANY hopes of performance gains, just because I like the way they look.

AU N EGL

Set the rake, get a proper alignment and then nothing but seat time

AtomicZ

Seat time. For most of us that is by far and away the best thing we can do.