Hiro

Hi everybody,
I'm currently trying to improve airflow through my main (engine) radiator:
My C4 is a '84 & as the 84-specific lower baffle is missing I guess I'll be faster fabricating something from scratch.
From various pictures I see there is a kind of deflector wing attached to the lower part of this baffle in addition to the spoiler central lip,
Also the upper radiator baffle has a strange box-shape that might be detrimental to directing airflow properly,
Has anybody tried yet to modify these features & get better engine cooling?
Pics & ideas extremely appreciated,
Thanks,
Hiro

leesvet

Keep it stock.
Thinking that you can out-think a billion $$ company with endless degreed engineers is, just silly.

The air box is designed this way for a reason. There is a single entry, BUT the air flow has to be split 3 ways.

1 to the a/c condenser to remove cabin heat trapped in the high pressure liquid in the condenser.

2 to the radiator AROUND the condenser, hence the need for some of the odd shapes. This is to direct "fresh" air around the condenser, not thru it.

3 for fresh air to enter above everything for the air fliter intake. That is why it has the "air-foil" mounted in the nose.
the car comes with a 'cold air' intake, but everybody seems to think that spending $350 on something that advertises "Mo-Power" will get them.....mo power. It usually won't.

if you are missing sections of the bottom, you can fab something out of plain 1/4" abs plastic, like hd mud flaps are made of. The goal is to trap the incoming air then direct it. As long as the bottom is sealed, the sides around the condenser are open and clean, the "pressure increase" in the nose at speed will send air where it needs to be. The Sucker fan behind the radiator helps make sure that the engine heat gets pulled out of that fresh air stream...

I tried this many many years ago and only made things worse. GM designed it this way for a reason.

if you want better cooling, spend the money on a better duel 1"cores radiator, and a better sucker fan. Turning the fan on sooner is a myth and so is a 160 stat. All that does is manage the lower temp only after start up. You want to TRY to manage the upper temps.... I have all the mentioned items and mine runs at 185 degrees all day without the a/c...even on hot days.

DUB

Like what was written above. There is NO REASON to try to 're-invent the wheel' here. If you have the mentality that it needs to run colder....then do whatever makes you happy.

I get customer all the time who are freaking out on how hot the car is running and I tell them that this is NOT HOT...and show them the service manual. Some accept to and move on...others are not going to give up and are on a 'mission' to make sure that they do something that they feel is better.

DUB

Hot Rod Roy

If you're missing your plastic "air dam" along the bottom of your radiator opening, these are available thru all of the Corvette aftermarket parts sources. If you're missing the "airfoil" or other brackets and panels, it's time to hit the recycle places. Stock parts work fine for anything less that full-bore racing 'vette's. Be sure both your a/c condenser and the radiator cores are clean!!

Hiro

Thanks guys for your inputs!
The radiator baffle assembly was modified just one year after the C4 release so I guess there was some room for improvement?
My C4 currently has no AC & is already fitted with an aftermarket double-core alu radiator,
Future plans include putting the car on a road race track (Le Mans track here in France) so any cooling improvement is always welcome.
I've also observed that the hood is pretty much crowded thus hot air should have a hard time exiting the engine bay,
Did you notice better cooling by cutting louvers or similar devices in the clamshell hood?
Also how far is it a good idea to directly bring fresh air from the bumper area?
I don't need the foglights so it would be quite easy to replace them with air scoops & ducts linked to the radiator upper baffle,
I like the C4 nose so I don't want to go into extensive mods anyway!
Hiro

DUB

Hot air goes out through the bottom while driving. So the hood being 'crowded' should not be a concern.

Cutting holes in the impact bar and front tie bar to allow more air in would NOT be something I would do. It will greatly reduce the front impact dynamics.

Using existing holes and running ducts is up to you.....all I know I would NOT cut anything.

DUB

pezter22

If you are looking for adding or pushing more air into the radiator you could look into adding the BP4 option auxiliary fan. It was an option for the Z51 cars. Mounting might be a bit of an issue for the '84, but there are mounting kits at mid america motorworks (corvette).

http://www.ebay.com/itm/85-89-CORVETTE-C4-AUXILIARY-BOOSTER-COOLING-FAN-/190886166678?pt=Motors_Car_Truck_Parts_Accessories&hash=item2c71b3c096&vxp=mtr

leesvet

Thing is, that fan is totally useless at speeds over 10 mph. Its there to move the smallest amount of air at a stop. It actually inhibits air flow at higher speeds, it blocks flow.

Hiro,
if you want to improve the scooping action to drive more fresh air into the "air-box" as its called, get a REAL air dam made of a plastic compound that is durable yet soft enough to flex a bit. The "Big-Mouth" brand seems to be a very popular air dam.
Be VERY WARY of the average fiber-glass air dam.....Those might LOOK good and LOOK like they do something, but MOST direct the air flow away from the entry and send it around the dam to be wasted and never getting IN the air box. I had a very popular model that caused my temps to go UP as speed increased.....not good.

Hiro

Thanks a lot everybody for advices & comments,
I've reworked all my track cars until they achieved very good cooling control so there's no way my C4 will be treated differently.
I have now two pushing fans in addition to the original pulling fan & this combo works decently,
So the overall cooling capacity sounds OK but the fans are very frequently on so there is room for improvement IMO.
Apparently it's "just" a matter of getting a proper airflow running all the way from under the nose until it exits the engine bay,
My guess here is every bit will help including sourcing the right spoiler & making the exit route easier too...
We'll see how it sorts out,
In the meantime I'm open to more suggestions, pics etc.
Hiro