Great article Team.

 

Does anyone else have an example of what OD is talking about being done on an RX8, to get better flow out of the radiator.
A photo of something would be great to see.
OD maybe you could jack up your car and take some photos.

 

Looks great, what waterpump are you using?

 

Mazmart's RE-medy water pump (+ Mazmart's thermostat)

 

I have a track event this w/e--when I jack it up to change the tires I will get a pic. Cant really see it well without jacking it up.
The plate in front of the radiator looks interesting too.
I wonder if you develop a high pressure pocket in front of the car with it? Probably really doesnt affect anything aero wise I mean?

 

Hard to tell, OD. I don't have data. However, it doesn't "feel" any different.

IMHO, if something creates a high pressure pocket it is the top side of the Series I grille (the top half that covers the crash bar); I've been thinking on just covering it with an aluminum sheet so it routes more air into the radiator area.

 

Adding ducting around the oil coolers will force air through the the cooling fins. without ducting air will follow the path of least resistance which is around the cooling fins. Some contact adhesive spray and strips of foam makes the job quite easy. At the track I see speeds of over 200 kmph and everything stays in place.

I also attached aluminium angles to the sides of my intercooler.

In the OP's case I believe his issues are different as I think bridge ported renesis runs hotter than the standard engine as this is the second case I have seen of bridge port and track racing leading to overheating.

Sure, he needs to look into ensuring the foam is in place and then test to see if it has made a differance.

 

which companies sell hi flow water pumps?

 

Did you forget to upload the photos OD?

 

I would like some input regarding this radiator issue. I'm building an RX8 for SCCA sprint racing and it seems the stock oil coolers are sufficient (I'll be adding an oil temp gauge though) but there is no consensus on the radiator. I will remove the AC condensor and 'plug' the gaps around the radiator, but according to the rules may only be able to use the Mazdaspeed unit or other stock replacements. From others' experience, would this likely be sufficient to keep the temps down? Some say the MS unit is no improvement, maybe a different option like Koyo? The dual pass Ron Davis unit seems most recommended but may not pass tech.

 

This is my setup. It is in place of the stock secondary oil cooler because I have custom center mount oil cooler mounted right up against the radiator. But if you can easily mount this right up again the radiator. This version is from Derale and comes with a fan but the fan is pointless honestly as it does nothing to drop temps since the coolant only stays in the cooler a short time.

So just find a good Long, Fluidyne, or Setrab brand cooler and mount it right up against the AC condenser. i just removed the condenser so I could get the mount pins thru and then bolted the condenser back up so the cooler is actually just mounted to the AC condenser. I am turbocharged with a water cooled turbo and my coolant and oil temps rarely get above 205-210F. And my AC works great in case you were wondering. This is in South Texas I might add.


http://www.jegs.com/v/Derale/259


http://www.flickr.com/photos/9krpmrx8/7394556276/http://www.flickr.com/photos/9krpmrx8/7394556276/ by http://www.flickr.com/people/9krpmrx8/, on Flickr

 

Do they really fail you for tech for cooling upgrades at SCCA? That sucks man.

 

Good sized oil cooler. Something to look at as a future upgrade, I am sure the fans will help in a traffic jam as no air is flowing over the coolers.

I added a wind deflector at the back of the under tray. I zip tied it to the cross rail and noticed the engine bay was a lot cooler. Before this application the intake pipes would get very hot however not it is cool to touch. The top of the radiator is covered so the hot air is directed down.

 

Looks good 9k, in Aus we only have 1 oil cooler standard and most people just upgrade to another factory oil cooler.

I like the idea of a custom mounted oil cooler as you can pick and choose your own size. I have always wondered if a single large oil cooler, maybe 50% bigger than stock + MS bumper + some ducting (foam or aluminum) to the oil cooler and a larger sump would be enough for an RX-8 in track conditions to keep temps at a healthy 95 - 100deg C.

My car will soon have a ron davis rad, mazmart water pump, removed a/c condenser and ducting/rad sealed around it, which will be more than enough for water temps at the track.

Skc we need photos please.

 

I run a stock radiator and don't seem to have the problems others here have. Perhaps it's due to the lower temperatures in the East. We haven't had a race day over 70degrees yet.

Clark: what class are you building to?

Arca, the SCCA class rules can be quite different. Regional tech in NASA and SCCA is pretty loose and they don't check for much. The philosophy is regional races are for fun and you should be honest. NASA Nationals, they crawled up my *** and inspected things I'd been running for years. They only really tech the top runners. And yes, if you are cheating you will be protested by someone. There are a lot of RX8s out there, so people know what it should look like. SCCA at ARRC made me take my header apart and intake to check for boring. The rules are different and at more prestigious races they can be quite scrupulous. Unfortunately, the reality is, there are cheaters out there. Get a placement at ARRC, expect to spend 3-4 hours in impound while they take the winner's cars apart. I've known people to slow down so they don't take third and have to sit there.

 

I will update my results after next weekends race. I have ordered the mazmart water pump, thermostat and oil psi mod. I have ordered a sump but I won't have fitted by next weekend. I have removed my ac completely and condenser. Hoping for a dramatic change.

H

 

That is a secondary rad, not an oil cooler, my secondary oil cooler is mounted in front of the radiator/AC condenser. The fan does nothing to drop coolant temps further in heavy traffic. A fan on the oil cooler also does nothing to drop oil temps any further in traffic. We have tested that locally using a nice SPAL fan setup.

Yeah if you do not have stock secondary oil cooler then that is the perfect spot for one. You could even look into placing a dual cooler there, that is what I am looking into. However, I did have a nice large 28" Fluidyne oil cooler mounted right on the front crash bar before i went turbo and that was the perfect setup, it handled temps great and cooled the oil off quickly after a hard run. But I had to ditch it when I went turbo due to the intercooler.

 

I like the dual cooler idea. My FI car can handle any daily driving condition, even driving in a heat wave.

However, I want lower temps at the track.

 

If I was to do my system all over (which I might do). It would be this way.

1. Ron Davis Rad properly sealed and ducted
2. FAL dual fan Shroud (410/420 (2500CFM) or 480/490 (3000CFM) with FAL VSC or Cobb to control them
3. Upgraded OEM pump or Mazmart Pump
4. Mazmart Thermostat
5. Stock oil coolers with stock thermostats removed
6. Custom -12AN oil cooler lines with a proper 180F oil thermostat
7. Upgraded oil pressure regulator
8. Secondary radiator plumbed into the heater circuit with a thermostat and located up against the AC Condenser.
9. Properly designed, vented hood (tall order)
10. Evans waterless coolant

But for now I have others projects to work on and my cooling situation is good to go.

 

a true race car won't need so much fan since it's only required for stationary idling conditions and they aren't likely to be using AC etc (this is a racing forum thread)

a small one on one side only is likely only needed and a crafty competitor might not even use one at all with the appropriate preparations

 

Wonder if removing 1 fan only would be a good mod for a race car - If so which one ?

 

I just used one fan.....big *** 3500cfm one...but it doesn't run long

 

That would be good for a street car.



What I would change for a race car is:

Ditch the huge fans, either use the stock ones or switch over to one small fan. Fans are really only good for when you're not moving, at speed all they do is restrict airflow even when they're running and make the alternator work harder. Unless you plan on doing a lot of crazy drafting. A lot of purpose built race cars like Porsche Cup Cars and the Radical cars don't come with radiator fans.

Secondary radiator shouldn't be necessary when using the huge Ron Davis dual pass. It's just extra weight. Might be necessary for FI track application though, but I've never seen a boosted RX-8 in race groups.

Removing A/C condenser helps a lot with cooling.

Regular Mazda coolant at about 25% coolant and 75% distilled water. Just because Evans is expensive and water/coolant is a better conductor of heat.

 

Most racing bodies won't allow allow any coolant so 100% distilled water is usually the only option.

 

My car had similar overheating issues I unbolted the top of the condenser and pulled it out about 6 inches. car runs much cooler and air-conditioning still works fine