Jedi54

iTrader: (7)

^^ nope.

Easy_E1

iTrader: (2)

Well since I put in the MazMart water pump it's been doing a better job of cooling down. It will still get hot in stop and go traffic. But as soon as you are moving above 35mph she cools down a lot quicker.
I am going to get Ray's new AT radiator here shortly. That should be the iceing on the cake. So to speak.

Jedi54

iTrader: (7)

yeah, the pump rocks!

having fun with the Nos?

Easy_E1

iTrader: (2)

The NO2 is working great. I am going to go to Jeff's a little later and see about some tuning on the AP. And then I might try the 65 shot jets in it. And maybe even the 75's.

Brettus

iTrader: (2)

just thinking about this for a moment .
The line at the bottom of the separator tank is a return line isn't it ? Are you saying that you would run the 2nd rad in series with this line ?
I would have thought there would be minimal flow through this line as the feed is the very small diameter hose that goes to the top of the sep. tank ......

PTY RX-8

Guys., I have the same issue with my AT 04 8. I live in Panama. Heres is very Hummid, and very hot.
I bought this car form someone who was selling at a bargain, the previous owner had overheating problem and parked it for like 2 yrs until I bought it. I change the Housing and Rotor Gaskets, and The Rotors Main Bearings. After that the car started like new, but.... a BIG but. Is still overheating. Since it was kept for so long, the Fan motor became unstable, I fixed it. Here in Panama we fix things, other than going to the Local Dealer that knows, almost nothing on this new engines. Anyway, I went today to a local friend and Mech, The solution, is:
PUT A 14" ELECTRIC FAN towards the Cars AC Condenser to blow more than enough air towards the car and to start when U start ur AC, It should solves Ur problem., I had the same issue with a Miata and did this and presto, problem solved.
Also, Use Castrol 20W-50 Thick Oil for a warm weather like Phoenix and Panama and wherever this issue is. Thicker oil works better, I have seen this recommendation around this forum a lot.
In The US, they change the Engine because it is on warranty, but what about UR time??? Does Ur time is not valuable? Unless they give Ua car to move around until they fix Urs, which they don't?
Try it. It should work. I am doing this by Monday and will post results.
Tks and Good Luck

Phil's 8

iTrader: (3)

The overheating problem occurs just about everywhere that excessive heat is present but seems to be less of a problem in areas of high humidity. Places like Vegas and Phoenix that experience multiple days of 4 -6 % humidity while the air temp is 117 degrees F + seem to have a larger problem. Thicker oil also helps as I use 20-50 during the summer. I believe that MM has tried the fan of which you post and did not have the desired results. You may have better results due to your high humidity.

theboy

i live in norrth borneo, climate here is hot and humid for the whole year.

we also have heat issue for the 8. normally we get 102 C when stopping at traffic lights or in bad jam. even with 50/50 coolant mixture.

as i know by far, vented hood is not helping at all.

does a better temostat helps?

Chamberlin

iTrader: (1)

Simply put, get the fan to come on sooner (many ways to do this), run 15% coolant, 85% distilled water, don't use your AC, your vented hood can help a bit, and stay away from traffic jams!

theboy

how to make the fan come on sooner?

Jedi54

iTrader: (7)

theboy: get the mazmart water pump.
You can get the temps to come on sooner with an AccessPORT (tuned by MM), with the Racing Beat Flash (but I think you live out of the US so that might not be a good option), if you can find the Mazsport cooling fan mod for sale (used since Mazsport is no longer in business)

Chamberlin

iTrader: (1)

this is an option too:

https://www.rx8club.com/series-i-do-yourself-forum-73/diy-flex-lite-variable-fan-speed-controller-123326/

theboy

Thanks guys its really helpful
recently my friend modified an extra fan on the back of the oil cooler, i was told it really improve the tempreture at idle and jams

Charles R. Hill

iTrader: (7)

This is one case where I would encourage the use of the BHR radiator. I am shipping one to Malaysia for use in a racecar that has similarly harsh climates it must endure so there will soon be tangible proof of the global applications it will satisfy.

Mazmart

iTrader: (12)

My RE-medy thermostat will be available soon to go with our water pump.

Theboy, is your car running one or two oil coolers?

Paul.

swoope

iTrader: (5)

really?

you dont say! before mid may? as you are going to miss the early march deadline!

beers

rodjonathan

iTrader: (6)

how much exactly did the pump help im thinking about getting one

shazy

Any update on this?

Flashwing

The pump has a completely redesigned impeller which is a vast improvement over the stock pump design. As it was pointed out to me, if you look at Mazmart's impeller upgrade it looks almost like the same design you'd find on a submarine. The reason being, the impellers on subs are designed to reduce cavitation as much as possible since cavitation causes noise!

Noise isn't our concern, but coolant foaming is. Paul could speak as to if there is any increases in flow but reducing caviation goes a long way to increasing how effective the cooling system is.

The thermostat seems to also be a great upgrade. A couple of the BHR guys tested them here in Phoenix and found them to work well. IIRC, the best part of the Mazmart thermostat is it will fail open instead of closed. In the even of a failure you won't have overheating issues and still be able to drive the car.

The other piece of the puzzle is the RX8's radiator. The stock radiator seems to be ok for temperate climates or normal street driving. However, the radiator's ability to shed heat becomes a problem on the track and in hot climates like Phoenix or anywhere in the south west.

Another fix is provided via the accessPORT with the ability to reduce the switch-on temps of the fans. The stock tune has the primary fan on full around 205 and the secondary on full at 215! By then you're already on your way to overheating.

I've found that on my own vehicle once I reach about 220 degrees on water and oil temps that it becomes much easier for temps to climb quickly. This is going to vary as my setup is almost completely aftermarket.

Finally, if you are in a hot climate you can switch to distilled water with about a 10% mix of anti-freeze. Water is the best liquid for removing heat. If you're in a colder climate chances are you don't suffer from most of these issues anyway.

All that is a round about way of saying that I believe the Mazmart pump is a worthwhile upgrade and used in conjunction with the stuff listed above it will help keep your motor cool.

All of this is subjective to your local climate and how you use your RX8.
Can you be more specific?

9krpmrx8

iTrader: (46)

If I do a drain how much coolant comes out?

The dealer will fill it when they put the new motor in but i would like to drain and fill it with just distilled water. If I drain as much as I can just from the radiator and refill with just distilled water would that be a good enough ratio?

ASH8

Just an observation here, when you compare what Mazda did with the 09's it may help some of you guys.

1. Mazda changed the water pump (to a plastic impeller!?) to 'reduce water pump drag' so they say.
2. Slightly Larger Radiator (manual only) (200 mils, less than a cup)
3. Gone to a 3 speed Fan setup instead of 2.
4. No change in the Thermostats or any other part of the cooling system apart from different Fan Motors, fan blades remained the same.

I am not convinced ANY extra holes in Hood or back of hood helps, may be better for heat to escape at idle or at stop lights, but when moving you are changing the air pressure flow, you need as much air through your radiator as possible, no where else.

The better the air flow through your radiator the cooler your engine.

I would be trying to decrease your FANS ON temp and if possible your fans speed with an Access Port or other device.

When you look at the evidence Mazda has done in Series II RX-8's was to increase Air flow through the radiator with an extra fan speed cycle, that is all.

Also, to help Oil Temps I would be opening up the extractor holes in the splash shields behind your oil coolers, this has been shown to help lower oil temps at the oil coolers .

https://www.rx8club.com/series-ii-diy-161/diy-improve-oil-cooler-air-flow-up-10-15%25-168650/

nycgps

iTrader: (1)

^^

if you just drain from radiator. you get about 2/3 of the coolant out. The last 1/3 will stay inside your engine.

All 13bs (not sure about earlier version right now) have this engine block drain plug, you can see it in FSM for older rotary engines, but for some reason Mazda feels that starting with Renesis, no one should play with that engine drain plug, so they made the drain plug MUCH smaller(the engine drain plug on my FC is HUGE), and not saying a word in the RX-8's FSM. (Its still there tho, I use it Every year )

but since you're getting another engine, the reman comes dry so. you're pretty much "all" empty.

You do need some EG (Coolant) to lube your water seals. so add maybe 10-20 % Full Anti-Freeze, then the rest just Pure Distilled water.

or just do all Distilled water + about 2 bottles of WW kind of coolant additive

9krpmrx8

iTrader: (46)

I think I will do that and open the slits in the splash shields when I install my BHR kit. I still need to get an oil temp solution.

Flashwing

If you're going to do a fluid drain you might as well drain all of it so there's no old fluid retained in the motor. You have to drain at the radiator and then there's a secondary drain which empties the coolant from the motor itself. There's a DIY here on the forum. It honestly adds maybe 10 minutes to the fluid change.

I believe the fluid system is approx 2 gallons but it could be a bit more. It's been a while since I flushed my system so I can't be exact. I'd just add the coolant first and then add the distilled water after it.

The coolant being added is honestly only for lubrication and to prevent the buildup of microbes in the water. This will prevent your coolant system from rusting, make sure all the parts are lubricated properly and ensure no critters grow inside your coolant.

I'd only suggest doing this if you are not in a climate where temperatures are close or below freezing. If it's a summer time thing that's fine. Just remember a mostly water coolant system won't be ideal for the winter time if it's below 32 degrees.

I could see the plastic impeller reducing drag on the belt system but in terms of overall life of the pump I'd be a tad worried. If a piece of the impeller were to chip off it could result in a total pump failure.

The high flow through the radiator was the basis of the BHR radiator design which we've seen a lot of success with.

Controlling oil temperatures is also very important but the solutions are lacking. Since oil absorbes/sheds heat much slower than water it can create cooling issues when your oil temps begin to get out of control. Currently the only solution is going with better/larger oil coolers but that's an install that's a bit beyond an average do it yourself guy IMO.

Going to a fan setup on the coolers has been looked into but the brackets would need to be fabricated because there isn't any room behind the coolers to mount fans.

I've been running a SEIBON vented hood for about 2 years now. I don't have any temperature data to say if the hood made a major difference or not. The primary benefits are at low speeds or sitting in traffic (which is where overheating tends to happen).

The stock hood can create a closed system by which temperatures will climb in the engine bay. The vented hood allows the heat to escape but there's no intake effect at higher speeds. Also there's no indication that there's any high pressure zones inside the engine bay to force air to escape through the vents.

Does it help? I think it does. It certainly doesn't hurt.

As for holes in the back of the hood...that's a discussion that's been beaten to death by both sides.

nycgps

iTrader: (1)

the system holds about 2 gallons and a quart of coolant.

Just dump maybe 1 quart of 100% Anti-Freeze, the rest just distilled water. it will probably cost you less than 15 bux.