mrc24x

I'm getting ready to install some cooling ducts for my C4 and need opinions/recommendations?? I am thinking about putting NACA duct inlets where the headlights would normally be instead of inlets mounted in the lower spoiler. Is there sufficient airflow if I go this route or am I wasting my time?? Thanks in advance!!

jwt1603

I wouldn't think you would get enough air forced in there due to the slope of the hood. I have (somewhere) old pics of a wind tunnel test on a C4 and the fogstream from the wand goes right up and over the hood.

My two cents of course.

Vetracr

The best place for a C4 brake inlet duct is under the bumper just outboard of the rub strips. This is a high pressure zone. GM engineers found this to be the best spot from testing during the Corvette Challenge series. On my C4 race car I installed NACA inlet ducts under the front bumper just in front of the spoiler. I ran these 3" ducts to the center of the rotor. I also installed inlet ducts on the front spoiler and ran these to the back of the caliper. Not brake related but I ran a cooling duct from the turn signal opening to the alternator, a Corvette weakpoint. FWIW.

Larry

ZR1 MK

Put them in the air deflector/spoiler.

astock165

Is this area the one highlighted from your avatar?

Gary04Z06

I picked up some NACA ducts also, I plan on putting them in front of the spoiler also. It is a high pressure zone and will give you the most air to the brakes. Just need to get some hose now.

ZR1 MK

Here is a pic of mine. Larry, how long do your
front wheel bearings last. Thats the weak point for me.
My rear bearings are still the original with 40k miles which
8k are track miles.

mrc24x

Thanks for the help everyone. The spoiler it is!!

96GS#007

Home Depot specials ...

Components (except Aeroduct hose):



Modified spoiler piece:


Driver's side spoiler:


Passenger side:


Underneath shot...

Umrswimr

Do you have any details from this installation? How did you route the hose, etc etc. This looks like the exact setup I'm looking for.

ZR1 MK

I cut the holes and mounted 3 inch scoops as shown. I used holes without metal screens for years, but later used it to help keep debris out of the wheels. Not sure it helps much as I still get plenty of rubber accumlated in the wheels. The hose goes up along the sway bar and is held in place with plastic ties to permanently mounted small cable clamps. I will sent you any pictures I have. My current setup works fine, but I plan to modify it for the future.

ScaryFast

How do you guys keep them attached? My car is very low, but from the above photos I'd say about the same as you. I had nice ducts attached in the same spot, but a lawn mowing session tore them off.


The occasional off-track is inevitable, do you replace them, or are your rivets robust enough to handle it? Did you reinforce the area? That little spoiler is only held on with some small screws.

ZR1 MK

Get the proper tools and stop cutting the grass with the Vette.
I used machined thread screws. No reinforcing, but no rivets . I went off the track once with the Vette. The right side hose came off, but the scoops where fine. The reason it came off was that I went over the curbing and I didnt tighten the hose clamp as much then as I do know. From memory, its 3.5" ground clearance at the middle of the spoiler for my car.

96GS#007

My ducting is held in place underneath the front fascia using zip ties. The rivets have always done the job of holding the adapter to the spoiler and the ducting to the adapter. When mowing the grass, the zip ties allow the ducting to slide fore & aft as the spoiler flexes. FWIW, the adapter and the ducting are gutter parts and cost me $3 total (like I said, Home Depot special! ) so if I destroy it, it's not a big deal. In addition, the zip ties will fail before there's any damage to the fascia.

The Aeroduct high-temp hose is routed from the duct back to the swaybar, then between the lower a-arm and the ps rack, behind the backside of the shock absorber, and then to the center of the brake rotor. The routing sounds crazy but it't actually straight forward when you see it in person. It's held in place with zip ties. I wrap the Aeroduct hose with duct tape and as the tape wears due to steering action, I simply put more tape on there (about every 3 weekends). I've been using the current Aeroduct hoses for ~3 years.

ScaryFast

The hoses were fine, I tore off the spoiler and the ducts mounted in it.

What did you guys use in place of the stock spoiler, which was stupid expensive to replace with a GM part?

johnno!

I'd love to see any pics that you guys may have, if you email them to me, I'll post them for everyone to see -- jbackman at destinycorvetteclub.com

96GS#007

I added a few pics to my post above.

CF6873

I decided to go with 2 2" hoses to get less squishing going through the suspension components. They have been working fine.

ZR1 MK

Here are some pics. I will post the scoop on Monday. You can see how I ran the hose. Early on, I wrapped the hose with header type material and drove carefully in the pits not damaging the hose much. As time when on, I got lazy and damaged the hose more frequently, so I fabed the metal guards. They are made from 25 gauge steel and will colapse if the situation is warranted, although you would be in real trouble if that type of turning is reqiured on track. This season, I plan to put a mounting plate and duct tube at the rotor. Possible reroute the hose differently too.

speedjohnson

Those pics are killer. Do the tires contact at full lock? I'm tearing up my tubes and replacing after every event... I've never seen such an "wide open" appearing space become so "small and tenuous" as the route to the C-4 brake rotor seems to be.