Vyndictive

iTrader: (28)

So first of all, I need to say that I have the Racing Beat Gauge cluster, because without this, I wouldn't be having a "problem"

My engine temps have always been a little higher than normal for some reason. I always just assumed it was the location of the RB temp sending unit in the lines.
(The gauges were on the car when I bought it)

Above 75F the car will cruise around 190F with oil temp at 180. However, stop and go or in traffic, coolant has spiked to 210-225, with oil following close behind at 195-210 range.

Another local confirmed that the temps were correct and not just location with an Accessport.

Autocross is where the spikes get scary, after a 40-45 sec. run, Coolant will be 225-226, and oil at 210. After 40 seconds!!! (I'm not very good) the temps do drop slowly between runs, but the time I had a re-run, I was worried about the car.


Relevant Mods: mazsport midpipe, AP catback, revi intake w/ duct. Catch can, water wetter, Racing Beat cooler screens, plastic engine cover removed, no front plate, Royal Purple 5w-30, throttle body coolant bypass mod.
I have never changed the coolant or flushed the system... what mix should I use for a summer car in Ohio? 70h2o/30coolant w/ water wetter?

I guess what I am asking is where to begin. I asked in the local thread and we're pretty much in agreement to try the RE-Medy thermostat and do a coolant swap first and see where that gets me.
We did agree that my "cheapest" idea of just removing the thermostat would be bad because then the car wouldn't reach safe operating temps and I could cause serious damage.

I have never done a full track day and will not until this problem gets taken care of.

I am curious if I should just order the package from mazmart that includes the redesigned water pump also? Would this address the problem better?

what effect would aftermarket radiators have? Are their significant advantages to an aftermarket design?

My fear is that I'm going to just play a guessing game: which is going to help "enough" to get my temps back down. And the real question, why are my temps higher than other rx8s with comparable mods, mileage, year, etc?

04' MT w/ 67k miles.
CEL is on, but I know its for the cat not working right... because I don't have one. However, I have not pulled the codes, so their could be one lurking in the shadows.

I think that about covers it. Thanks all.

czar

iTrader: (3)

the water pump may help it cool faster
the bhr radiator is a good option

ive been wondering on how to help cooling also, i was just doing a mild run though the hill roads, saw my water temp hit 230 and backed off

EDZRIDE

iTrader: (1)

I would suggest you have the radiator flow tested before you replace the coolant.

Removing the t-stat will also cause overheating on a hot day.

I think you are on the right track, good luck with your efforts.

Razz1

If your really wooried change the fuild twice a year. 20/80 water for summer.

Mazmart water pump
raise the back of the hood with washers and remove the weather strip.

Run 20 -50wgt oil

Plenty of cooling threads.

Jedi54

iTrader: (7)

your cruising speed doesn't sound too bad.
This morning it was about 73°F and when I first got on the freeway I was at 186°F and it eventually settled at 179°F (cruising at 85mph)

your stop & go temps seem a bit high if you're seeing them at that ambient temperature.
Have you verified that your fans are working properly?
Since you're tracking the car, I would definitely look into getting a BHR radiator and the Mazmart water pump.
The pump is far superior to the OEM and will help against cavitation. The radiator is also a big piece to the puzzle.

Definitely get the coolant system flushed out. OEM is 60% coolant , 40% water. IMO that's too much coolant. I think you'd be better off with 60/40 (water / coolant) or even 70/30 with a bottle of water wetter.

9krpmrx8

iTrader: (46)

The fact that you have never changed your coolant is a start. Also, although it is rare on a street car, could your radiator fins be clogged with dirt? Definitely getting the radiator flow tested and checking that your fans are working properly is a good idea.

Vyndictive

iTrader: (28)

Thanks for the input guys.

Some good suggestions for sure... some cheap+quick and easy (the way I like my women too!)
Some expensive and rather time consuming.

Does the raising the hood with washers and removing the weather stripping really reduce temps significantly? I mean, it seems logical, but I don't know, the gains would seem marginal at best for something like that.


I know there are a lot of ways to get the car to run cooler by a few degrees, but my fear is that there is a deeper issue causing me to run hot, but I don't know what that could be?

Do you think this is just normal rotary heat soak? or is something malfunctioning causing me to run hot?

Accessport confirmed fans are working properly and kicking on when the should.

I'll check the radiator for debris (maybe a plastic bag is up there, or worst case... a cone from autocross. )

Is it safe to flush the radiator with non-distilled water as long as you're using distilled for the coolant mix? I've replaced a radiator before on a much easier car to work on, i'm not too worries about that, just want to damage the radiator.

I'll start with the thermostat water pump in terms of new parts, then flush the system and replace the coolant with 70/30 with water wetter and see what that does. I probably won't do it for another few weeks because I'm riding the motorcycle a lot.

I'll report back with how it seemed to work.

Thanks again for the suggestions.

Race Roots

iTrader: (64)

https://www.fluidmotorsports.com/p-1...e-cooling.aspx

Oil Cooling fan kit will drop the Oil temps by 30 degrees

The Fan control kit will make the Radiator fans kick on sooner thus driving down coolant temps.

Very good bang for the buck.

Temperature control is very important and scary and why I don't mess around and ignore it when it comes to things like that.

Vyndictive

iTrader: (28)

Yeah, I saw those... but. . .
This is fair warning that I am going to be highly critical of these new products and present, what I feel, are more cost effective alternatives.

That said, I've done business with fluid in the past and would buy from them again...

Fan Control Kit... honestly, I would just hard wire the fan in and have a switch in the cabin to turn the fan on manually, a switch and wire from autozone and beer, 10-15 bucks?.
Had this in one of my older cars and it worked very well with a perma-cool fan.
However, you can't be an idiot and forget to turn the fan on, or else you'll ruin the engine, like the dude that bought the car from me.
For 175-200 bucks, you can pick up 2 high efficiency electric fans to go with your hard wire.

Oil Cooler fans:
I'll try this first...: https://www.rx8club.com/series-ii-diy-161/diy-improve-oil-cooler-air-flow-up-10-15%25-168650/
Compare 175 per fan to 175 for additional oil cooler with fan... yeah, its more work to install, but you'll increase oil capacity, and have 3 oil coolers, 1 with a fan...

G-ReX

I think you're right in looking for problems first; that's a high temp for just an autocross. It took me four 20 minute track sessions and cumulative heat soak to briefly spike at 221F water temp on a 90 degree day.

It's been proposed that the RB duct may impair air flow. I'm considering pulling mine for the track.

Vyndictive

iTrader: (28)

Well, track would have much much better airflow than autocross...

I don't think it can be the Ram-air duct because 2 other locals have the RB intake with duct and one has an accessport to monitor temps, and the other has gauges to monitor temps... i still run hotter.

staticlag

I would start with the water pump. Its quite worthwhile if you plan on being at high RPMs for any amount of time.

staticlag

https://www.rx8club.com/showthread.p...ght=water+pump

Vyndictive

iTrader: (28)

Ordered the thermostat+waterpump combo from mazmart today... I figure that, plus a coolant flush should take care of the problem.


Static - just read your thread about your pump experience. I noticed a lot of my problems either after autocross runs or in stop and go traffic - low speed.
You said this may hurt idle coolant temps. Do you think this could be addressed by the thermostat also?

olddragger

iTrader: (3)

contact fluid, he may have a new product? Not the oil coolers.
olddragger

savedsol

I've got the Mazsport fan control kit. Before my fans pretty much never came on. Now they are on all the time. 15 min trip in stop and go and 71 deg this morning and they came on. I know they come on at a much lower temp but I'm wondering if I also have other issues. No gauges to give you numbers.

Red Devil

-Secondary radiator (can be had for less than $100 from Summit - we used the same as Oldragger's and it works) place it up front like a FMIC, or on a modified undertray like Pettit - you will see a 15-20 degree swing at the race track with this mod. I think Pettit's upcoming auxiliary radiator mod will be the best offering for anyone looking to purchase radiators for the RX-8 and that includes the one's already being offered as direct replacements.
-70/30 water mix + water wetter (we used Royal Purple) - between those we've seen a 5-6 degree swing at the race track
-Mazmart Water Pump, definitely brings down the coolant fast as compared to stock

IMO, those are the three best bang for the buck options.

Huey52

iTrader: (2)

The RB Duct intake is above the airflow to the a/c condensers and radiator, so non-interfering (and the OP cited no front license plate).

My ambient/coolant temp numbers are as Jedi54, so obviously you're high.

As already recommended flush and fill your radiator and make sure you have clear airflow thru the radiator fins. 50/50 coolant/distilled water is plenty for Ohio (e.g. Dextron pre-mixed). Flushing with distilled is prefered, but not absolutely necessary as you'll end up with distilled.

The quicker opening Remedy thermostat would help as well as a stronger water pump.

Also enhanced oil cooler fans and a larger oil sump as another option (Fluid has a nice low profile/gated model).

And of course the BHR radiator.

But you should first get this sorted out in your present configuration before you go throwing more hardware at it.

Vyndictive

iTrader: (28)

Well, since the thermostat and water pump, my temps have been way down.

I did the coolant change, flushed with distilled, (burned the F$%^ outta myself cause I didn't want for it to cool) and then put in 70/30 distilled water and coolant. Still getting some spikes, but a tire sprayer on the oil coolers at autocross has helped alot for autocrossing in 80+ degrees and solid sunshine.

I'm thinking the problem may be with my fans not coming on right away.