Jeredk21

Having cooling issues when running hard on the road course. Already running a DeWitts radiator. Looking at buying the spal fans and interested in leaning the radiator forward and ducting out the hood. Open to thoughts and ideas.

My Vette Life

Have you ever considered the License plate filler mod?

Basically removing the the filler panel and create an opening, that will definitely keep the engine and engine bay cooler.

I did this mod but haven't tracked the car yet, but I do see a big temperature difference.

pewter99

running Dewitts with SPAL....did this to help keep my Maggie car cool

https://www.corvetteforum.com/forums...post1584139932

works fantastic at speed

Reggie Dunlop

How hot? What temperatures are you seeing?

555ss

In our cars the stock fans were a restriction to air flow on track.... We switched to Dewitts aluminum framed fan set up and it worked VERY well the 4 rubber "valved" doors and the larger fans seam to let a bunch more air thru and the temps dropped.
we then went to the track spec vents mostly to help with front end lift at speed. there was only a marginal drop in temps by adding the vents..

Hi Volts Z06

The stock C5 water pump is the weak link. The BEST solution is a new Evans water pump. Call them and discuss your setup and they will build you the best possible unit. I struggled for a long time with this and the fact is that as you get faster and drive harder that unit cannot keep up. You do NOT need to run the special coolant that Evan makes. Once you speak with them you will see that they are experts in this field (they built the water pump for the C5-R and C6-R Corvette). The level of service is excellent.

Leaning the radiator forward and venting the hood will help to some degree but will not be enough to solve the overheating issue.

I have heard that the LS-3 water pump is a much better unit and lighter if you want to go that route but I can tell you that for a few hundred dollars- you will never outgrow the Evans unit.

Jeredk21

Thanks everyone, I did do they license plate mod, I'm running hood vents from John, I have talked to guys at evans and they are extremely smart when it comes to cooling. I did the temporary shutoff valve and then removed the hoses to the heater core when cage went in and heater core went out. Run water with water wetter. Made a scoop from my splitter.

Hi Volts Z06

I'm not so sure you are getting enough air in to that radiator. The grill material at the plate mod is very fine so your are losing a lot of flow there. You might want to go to a coarser material to allow more flow. Second- the spacer for your splitter is very thick (although I do love it- nice piece) so you are closing that area off too. I'd lose those fog lamps and use that space to take in air.

charger21

I would start with the Dewitts spal fan set up first. It is for sure a upgrade from the factory fans. I just installed it on my car and they say the fans flow twice as good as the factory set up.

quick04Z06

Do you have a separate oil cooler, or is your new radiator also an oil cooler? If not, then add the oil cooler--should fix your problems as it did on my C5Z. I ran at Road Atlanta in August with a combo radiator/oil cooler, 180 thermostat, stock fans, with no issues.

brkntrxn

A couple of things:

1. I run a DeWitts in the stock location and feel it is enough for the car, along with:
2. License plate mod
3. Cut lower bumper cover to make the opening between the bumper and the splitter taller
4. Engine oil cooler
5. Vented hood
6. Spal 14" fan with no shroud covering any of the back of the radiator
7. No AC condenser

and MOST importantly

8. A full sealed radiator shroud - top, left side, right side, AND bottom. You have to force every single bit of air through that radiator. I have watched too many people not seal the bottom of the radiator and that is where a LOT of the air escapes.

For #3 above, go to post 79 here: https://www.corvetteforum.com/forums...z06-build.html


I race in the hot, muggy southeast and have had zero issues with coolant temps since installing the DeWitts. I already had everything else done trying to get the stock radiator to handle the heat. The DeWitts was the final piece of the puzzle.

-Kevin

Bad Karma

I think this is the biggest restriction, if you look at the race bumper for the C5R, they made the opening quite large when switching to front feed.

Mark@AMT Motorsport

To direct your question about leaning the radiator forward, I took out 40ish degrees by doing so and making a decently sealed air box. I was 210-220 last year with the Dewitts, and after leaning the radiator forward I was barely above 180 at NJMP last week in 84 degree heat. I thought there was something wrong with my gauge!

Hi Volts Z06

A fan has no effect once the car is moving at track speed. You need the proper sized opening based on total area of your radiator core. I can't find the exact formula but I think it's like 75% of the area. I'll try to dig it up.

Jeredk21

My screen is 1/4 race mesh. My picture is bad but the splitter has a large hole to allow air in. I have radiator sealed to force air through. Also running setrab 19 row oil cooler with improved oil block with 180 degree stat. Speaking of thermostat the car has 165 low temp in it also have fans to come on early. Water reaches 265-280 with oil 270-300

Jeredk21

Better pics

Mark@AMT Motorsport

Water 265-280!? The gauge only goes to 260, how do you know it's getting to 280? I thought the car shut itself down at 260.

Anyway looks like you're running the ACI chin spoiler like I am. I'll take a picture of what I did to mine and my bumper tomorrow to open it up to allow more airflow. I would say you definitely need to cut the front bumper to allow more air to enter, as Kevin noted.

I also wonder if that hole in your splitter is actually doing anything to get air into your radiator. Don't forget in stock form the car has an air dam to build up pressure under the car to slow the air and suck it in to the radiator. I'm no aerodynamist but I think the fast air under your car would mostly blow right past that hole in your splitter and do nothing for cooling.

edit: ah crap unless that's actually a"scoop" I see in that picture - then it seems like it should be doing something...I still think your main issue is the size of the opening in your bumper. Mine is at least twice as big as that.

Hi Volts Z06

I also have to question all the different places you are trying to take air in from. At some point perhaps you are causing turbulence and air is acting as a "curtain" (think of the air curtains at the doors of supermarkets that keep the cold air out). I would open up the area between the splitter and fascia and then lose those fog lights and have everything ducting from the front. For now close up that "scoop" as it might be hurting more than helping.

Also- can you post up a picture of how you have your steam ports routed? I've made the mistake myself of trapping steam in the engine and that just gets worse. Have you ever "burped" the engine?

Lastly- you make no mention of the water pump. I'm telling you that once I went to an Evans my problems went away but maybe I could have solved the problem with an LS-3 pump. Perhaps you just have a crappy stock pump. Take a look at your upper radiator hose when the car is running and thermostat open. Is the hose hard and pressurized or do you just feel water flowing through part of the hose? Flow is the key to cooling.

brkntrxn

I would seal that bottom inlet underneath the splitter. Like others said, that could be causing an issue rather than solving it. Air pressure wise, the bottom of the splitter is a low pressure air in regards to the front of the bumper cover. So even though you have a "scoop" you could still have air leaking out of that bottom cut from the high pressure air coming in from the front and stacking up against the radiator.

Force ALL air to come in from the front AND open up your bumper cover more. And cut the center bung in the ACI splitter piece as well.

If you will seal that bottom opening under the splitter, my bet is you will solve your cooling issue AND get more downforce on the front end.

Jeredk21

Thanks everyone, I will get ready to cut that bumper up and get more air in. I checked my logs and water is 245-260 when getting hot. I do have a stock 98 ls1 water pump with 125k on it. Time for an evans.