I am ready to spend what ever it takes to make my 6.8l, Procharged, 810 hp C6 cool.
I have the largest Dewitts radiator. A 112 sq in EOC. 160* T'stat, and Dewitts 17" brushless Spal fan and shroud.
Look for a cooling fan set up that sucks so that it will pull the car forward !!!

Thanks in advance

 

A lot of people swear by the ProSpeed dual fan set up. When CPR did my build, they said many high HP guys use them and it's the go to set up...FWIW.

They do draw a shitload of amperage, though...

How does it do when cruising at 45 MPH or greater? If it's still running hot, the fans aren't the issue...

 

so a radiator and prospeed fan setup works for 90% of the guys out there. If you're an auto breakout the trans and oil cooler (if grandsport) that helps.

Now I have two solutions for people that is end all be all.

1) i cut the front support to allow more air through (it blocks a lot) think of a c7 setup. and if PD blower we do a small aux radiator.
2) if procharger setup go air to water and our cores under the headlights. the car will run as cool as NA and make more power.

 

Thanks, guys
ProSpeed was the name I was looking for.
From what I understand, it would also be a good idea, perhaps mandatory, to also upgrade the alternator?

 

I did, but my voltage dropped to <12 volts at idle with the fans maxxed out.
Could always just try the fans first...

 

I added the DeWitts Radiator Electric Fan Upgrade Kits 32-SP463SC kit. I talked to DeWitts. They told me the part number for the Spal fans. 30102052I looked up those specs, 30 Amps per fan is the fuse recommendation.

There is no way the stock alternator can source that much current at idle so you will see the voltage sag at idle and the fans are not spinning at full speed or probably very fast at all as they are sharing whatever little power the alternator is making with all the other systems of the car.

I am putting a Mechman 140 A alternator in next week.

I do not have evidence but it is unlikely in the extreme that the factory Pulse Width Modulator (PWM) which controls the speed of the fan(s) can source enough current to power the Spal twin fans. I installed a Solid State Relay which is connected directly to the battery on the switched side. I have a 50 Amp fuse which has not blown yet.

The PWM drives the 'coil' side of the SSR.

AFAIK the Spal 11" fans in the DeWitt kit are the most powerful 11" radiator fans available anywhere.

The only think I could see about the ProSpeed setup that was better is the fans and shroud are set back a little from the radiator so the fans can pull air from the entire radiator. The DeWitt's is not is only pulls air from directly under the fans. There are flaps on the shroud so when you are moving air can push through much of the radiator. I am going to put a 1/2" or so spacer under the to and bottom of the shroud and some sort of weatherstripping along the sides so the fans can pull from the entire radiator.

I put two bottles of VP Racing Fuels Cool Down in the system. Seemed to help some.

I will be watching this thread with great interest as mine does not keep as cool when the temps are much over 90 degrees as I would like. If the ambient temps are 85 or less, it does fine.