It's not uncommon for some tracks/event organizers ban the use of glycol in coolant.

Oh yeahhhh. It's as slippery as oil if it happens to exit your car due to unfortunate events.

From the NASA CCR:

15.18 Engine Coolant:

Glycol-based antifreeze or other additives that may cause a slippery condition if spilled on track are prohibited. Other water additives such as Redline Water Wetter may be used.

I should not have confused the situation by mentioning comp school. Stepping up to wheel-to-wheel in general will require me to take the antifreeze out of the cooling system.

correct, nasa and most other racing organization doesn't allow using antifreeze.

I asked because my driving and comp schools (albeit way back in the day, at Lime Rock and Summit Point) allowed anti-freeze. I understand not allowing it actual racing. Cheers

Redline Water Wetter is an old formulation that is incompatible with many modern coolant additives--even residual residues. It polymerizes in the cooling system and creates brown or black sludge. I can't believe it is still being sold.

Motul MoCool is what you want to use with distilled water as a corrosion inhibitor and water pump lubricant.


My Series 2 car is stock under the hood, except for a Koyo HH radiator and foam, and my peak coolant temps are 216F at the track on hot days. No idea what is going on with you guys...


https://cimg7.ibsrv.net/gimg/www.rx8...fea3436fdb.png


I am running 40% glycol courtesy of FL-22. Once my engine warranty is up, I may switch to water and MoCool, since my car never sees freezing temps.

Oh, the horror.

Previous cars of mine have experienced the floating brown tar AND slimy brown gunk deposits!

It should only be used with 100% water, and even then there are better products.

I appreciate your input. I bought the Redline product because I'm busy and hadn't found an alternative. I'm not a big fan of the snake oil brands like Redline, Royal Purple, etc. I just want to put a corrosion inhibitor in there.

After draining the coolant. I plan on taking the car outside and flushing out the engine and the radiator with a hose. Hopefully I get what I can of the coolant out. Since distilled water is cheap, I'll likely flush it out, fill with distilled water, run it for a bit, drain, and fill again.

Generally speaking, Redline does not sell snake oil, IMHO. I have used their gear oils and CV-2 grease for years and have been perfectly happy with the results. WW is an old product that has not been updated and should be pulled, but other than that, Redline is fine. Having said that, I have never been inclined to use their motor oils, as I find Mobil 1 to be perfectly fine for track use, and used oil analysis backs me up on that.


Royal Purple, OTOH...

After replacing the water pump and flushing the engine and radiator out with a garden hose, I put everything back together, filled the car with distilled water and warmed it up. The external temperature gauge, being on the upper radiator hose, reads 5-10deg higher.

Temperature stabilized at about 200degF, as verified by the external gauge and OBDII. That seems a little high to me for just idling on jack stands. If I hold it at 3k, it'll get just warm enough to turn on the fans at their stock temperature.

I have a new CSF radiator on its way. I have a banged up one I may install just to see if it changed things. Why not? I want to drain out this batch of water anyway, in case there's some remaining coolant in there.

Unless you've changed the fan trigger temps, 200 seems about right.

Lucky you! The only difference I know of between our setups is on the driver side of my radiator, my current foam setup leaves about ~1/2" still open. I do plan to remedy that but can't imagine it would make more than a few degrees difference. When pushing the car at a time trial at NCM I was easily getting it over 220 at which point I backed off. With 2 drivers, there was sometimes only 5-10 min between sessions which may have contributed.

Yeah, I have a MazdaManiac tune on my Cobb AP, which does lower the fan temp. I also have Cobb's standard 'stage 1' tune on there. I wonder if that drops the fan temp as well.

I don't think it would matter anyway. The problem is on track. It was bad enough at Mid-O by the second day last time out that one or two laps would get it up to 220-230. Hopefully flushing it out and replacing the pump and radiator will make it happy. I'll block three sides off with foam for now until I can properly duct the inlet.

I leave for Gingerman on Friday. This morning I fired the car up, now with a new water pump, new CSF radiator, distilled water in the system and new foam on three sides.

I dare it to overheat this time.

according to my obd2 reader guage thingy, with a koyo, and the fans coming on at and realier time it reads 180 at idle and normal driving speed but once i turn on the ac and drive in bumper to bumber the temps have gone as high as 210. i bought a new mishimoto thermo and will be buying the fans and shrouds idk but im not too confortable with the temps reaching that high. is that normal?

^ That's normal. Actually, it's better than average.


For context, a healthy Miata's coolant temp will reach 230F cruising down the highway with A/C on a hot summer day with its stock cooling system, and that is considered perfectly fine. Imagine how hot it gets in stop-and-go traffic!

Of course, the RX-8 is not a Miata, and we want it to run cool enough to keep the silicone seals happy, but we often make too much of it. Mazda says 245F is within spec. 230F is probably a safer number. I am happy if my CLT stays below 220F on the track. As you can see in the chart above, 216F is its normal peak under constant heavy load (6000-9000 RPM) in 100F ambient temps, and that doesn't concern me at all.

I'm not an engineer, so take it with a healthy dose of skepticism, but... Lowering your thermostat temp below 180F is not a good idea. Coolant heats up faster than oil, and part of the coolant's job is to help heat the oil past 180F as the car warms up. The thermostat sets the floor operating temp of various parts of the system, and you do not want that floor to be lower than 180F. Also consider that thermal expansion of engine components is calculated at some "normal" operating temp, and excessive wear happens below that temp, as the materials that make up various parts have not fully expanded. Normal operating temp for the Renesis is undoubtedly higher than 170F.

If you are still concerned and want to make a change other than the oil cooler thermostats, buy a FAL shroud (search for the part number on this forum). FAL stuff is much better than Mishimoto stuff, and the FAL shrouds (there are 2 that fit) have been well-tested by forum members, including boosted members.


(When we see equipment failures at the track, we look at each other and take bets on whether it was some Mishimoto part that failed. It is a really safe bet that it was. Oil cooler kit and timing belt tensioner on 2 different cars last weekend, for example.)



.

the reason why im slightly hessitant is i just got the motor rebuilt, and the temp went a little line more than half with the ac on and i do not want to rebuild this ish again since i have to finish my firstgen

How hot was it outside when the needle moved? You're right, it shouldn't get to that point under normal circumstances. The needle starts to move at 230ish. You shouldn't need mods to keep it below that, potentially something is up with your cooling system. Especially if it didn't do that before the rebuild. Obstructed flow, broken fan, not pressurizing. etc.

It’s 99 outside right now in Miami, it got up to 228 and that was without the ac being on. I still think being that hot is sketchy but idk. I do not have the undertray nor the foam around the rad I will be ordering that soon, any recommendations

Undertray and foam are must-haves. They serve to force air through the radiator rather than allowing air to flow around it. Air always follows the path of least resistance, and through the radiator is the path of most resistance. This is very important with speeds over ~40mph.



Under ~40mph, the fans do most of the work, and the undertray and foam matter less. If you have an older car, the fans may have slowed down due to age. It is common with this car. It is also common for a rubber grommet to fall out of the airbox and lodge in one of the fan blades and burn out the motor. Replacing them may be a good idea. Have you tested the fans?


You can replace just the motors, the whole shroud, or you can install a FAL 420 or FAL 490.

I have the undertray and foam and also:
http://shop.pettitracing.com/aluminu...-p-120224.html

I added this to my cooling system from Pettit Racing to get rid of any trapped air. Might be overkill, but it seems to be working fine. I also added other cooling mods, like new aluminum Koyo rad, lower temp fan switch kit, lower temp thermostat, better water pump, and oil cooler lower temp thermostats, plus all new silicone hoses from Racing Beat. Together everything is running lower temps (read on OBD2 reader) for my move to Texas and its summer heat. Drove my RX8 straight from New Jersey the 1500 miles to Grapevine, Texas (near Dallas), Driving for stretches of ten hours straight with air temps over 90-95 degrees and at high speeds with a/c on, and the coolant temp stayed between 190-195 degrees. Nice.

i had one replaced. not the other. i think what i am going to do is buy the fals and the undertray

Throwing parts at the car seems to have helped. Granted, it wasn't very hot all weekend, but the external temp gauge never went about 210ish. That feels entirely acceptable to me, and is an enormous improvement over 240.

I'll keep trying to improve it, but I think at this point I'd need to improve oil cooling first.

For my next event I'll probably try a larger water pump pulley and replacing the fender liners behind the oil coolers with mesh.

just ordered my fal 420's. im still cruising temps at 180-183 and when im in slight traffic with the ac on i hit 205-213. i do not have the undertray nor the foams. will update you once install also i did order the mishi thermo so this weekend the cooling system should be done.

in the future i'll prob end up buying the mazmart water pump.

^ How is dropping your thermostat temp ~10F going to improve your temps in "slight traffic," where the stock thermostat is completely open? That's where you need an undertray and foam. Alternatively, one of the lower temp fan turn-on kits would help there.



All you are doing is delaying reaching those same peak temps by 30 seconds or so. I hope that's worth $60...