mountainbiker2

I only use my C5 for autocross. I installed a Splitter with under tray not to long ago. I have a choice of 3"x 24" 3"x 18" and 3"x 14" opening to feed the radiator. With the 3x24 the water temp. was fine. 3x18 just a little hotter. I really wanted to use the 3x14 opening. Smaller the opening more downforce, but the water temp. was running 235. Probably a little to hot. I decided to buy the DeWitts radiator with no oil cooling. My last race with the radiator, my car ran 225. With about the same ambient temp. Not a big change, but with so little air coming in, I feel that's pretty good. The radiator is made very well and the fit was perfect. I made fun of there advertising with my friends "Direct fit", because lets face it, nothing is "Direct fit", but this was to my surprise. I'm going to install there "Direct fit" fans and I'll let you know how that goes.
3x14 opening.










Steve A.

CHJ In Virginia

The DeWitts is a superior radiator that will deliver great results. You have to let that car breathe better. Moving air is the key. IMHO the amount of downforce difference between the smallest and largest openings is minimal and you or the clock would never notice on the average autoX course. If you are going to restrict the air coming in, at least make a way for what gets in to get out easier. Cut some hood vents or something to improve airflow. Cool engines make more power.

Painrace

You must get more air out from under the hood which will also increase front down force or reduce front lift.

Jim

mountainbiker2

I have a vented hood.

RogerT

I have added a remote control (key fob) fan relay where I can keep the fans running all the time if I want.

You might consider doing this.

Roger T : )

froggy47

Just curious on the fans. You going with one big SPAL fan? Does that weigh less than the two stock fans? Move more air? Both?

My stockers seem fine so far.

Cobra4B

16" Spal wired into the OEM circuitry here... way lighter than stock and moves plenty of air. Fan turns on at 215 and goes off at 205. Cools down very quickly.

Black89Z51

Curious where those hood vents are from.

Cobra4B

They're not add-on vents. It's an ACP hood.

LEAVINU

In addition to the fan weight differences what's the radiator weight differences?

skyavonee

I'm also curious about the dry weight difference between the two. Separately, the Dewitts unit has extra hidden weight if it holds more coolant than the stocker.

froggy47

I don't have any weights, but I am confident in saying that an all aluminum radiator (dry) with double the capacity (think of the core construction & thickness) is at least 50% heavier than the much thinner oem with plastic tanks. Maybe 100% heavier.

Higher capacity radiators are not for saving weight.

mountainbiker2

My stock ones worked okay, but I wanted to cool the engine down faster. Plus move more air through the engine compartment. Don't forget I'm running a Splitter with a very small opening.

ACP Hood.

I'm fully aware of the weight difference. Water too. Some things you just have to do. I added 55 pounds to my car with Aero, Radiator and Fans. I'm hoping that the Aero will over come the weight difference. I have not installed the fans yet. When I do, I'll post a review and weight difference on a separate thread.







Steve A.

HC Mechanic

Awesome fan setup


Will that work with the stock radiator as well?

mountainbiker2

Yes.

LEAVINU

Definitely understand the need to add weight at times to make it faster in the end.

Surprised at the dry weight difference of the two radiators but again like you said it's not for weight savings. That fan setup looks killer and I'd doubt you'll have any issue moving air now.

LEAVINU

I wonder how this 16" Spal fan compares to the 16" OEM C6 fan? Would their be an increase in airflow for the C6 guys by swapping? I was about to order a dual 11" setup today but now this has me wondering. Thoughts anyone? Any CFM specs for these kinds of things?

mountainbiker2

The DeWitts fans for a C5 claim 3200cfm which is double then stock.

Steve A.

Supercharged111

Looks like a single 16" Spal fan promotes superior airflow through the radiator. I see you don't have AC, but for those of us who do, would this non-shrouded setup be better than stock (seeing how they apparently flow more than stock)

trackboss

I run a spal 16" puller extreme paddle fan and it moves a ton of air. Seems to be more so than the factory duals, but I have no data. There is actually a slight vacuum at the inlet under the bumper cover. And, that is through a dual 1.25" (thicker than any of the direct replacements) core radiator with low fin count. Having done this a 1.5" would have also worked. I was concerned it would have been too thick and created over heating at low speed regardless of fan. I build my own custom system, but it will give you an idea. The shrouded fans restrict airflow at speed and create lift.