hufflepuff

folks,

the S2 radiator fan assembly is different than the s1 - and i might have heard rumors that it's a potential upgrade due to higher flow rate. has anyone tried swapping the S1 fan assembly onto a S1 radiator? looking for a little extra cooling capability during low speed events like autocross.

EDIT: looks like fan blades are not different, but the fan motors are...
https://mazdatrix.com/product-catego...-systems/fans/

The S1 motors are way more expensive than the S2.

And i also wonder why the left radiator fan is funny shaped / uneven, and the right is symmetrical. maybe for noise? but i wonder if i could simply bolt on two right-side fan assemblies if that might move more air?

spectre6000

I haven't been looking or anything, but that looks like the first S2 part I've come across that's cheaper than the S1 equivalent.

Additionally, it's crazy how much was changed between the two generations, and at what level of detail.

The asymmetrical fans are for noise. I imagine the low-noise fan probably comes on at low speed, and the symmetrical one (higher flow) only comes on when more air flow is needed.

hufflepuff

Looks like the S2 went to three-speed fans, and there are wiring harness changes.
https://www.rx8club.com/series-ii-te...-temps-205997/

hufflepuff

to me, the left fan motor looks very similar between S1 and S2, just two wires vice three. but the right cooling fan looks smaller, and the manual states much smaller current draw:
https://foxed.ca/rx7manual/2003mazda...215140W02.html

hufflepuff

continued research:
https://www.rx8club.com/series-i-tec...nto-s1-252835/
https://www.rx8club.com/series-ii-te...mps-s2-217031/
https://www.rx8club.com/series-ii-te...-temps-205997/

TeamRX8

iTrader: (25)

are you under some rule stipulation that requires OE fans?
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hufflepuff

Hey Team- no, i am not. i had considered the S2 assembly as being "OEM-like" and i can get a S2 fan assembly for <$100. But it sounds like if i'm doing wiring changes and some fan shroud attachment changes, i might as well consider an aftermarket setup. Have you in the past experimented with the popular FAL420 setup??

TeamRX8

iTrader: (25)

that’s why I asked; that OE junk is never going to cut it or be even close to the same flow as the FAL 420 or 490

Even if you have software to set the fan temps, I do recommend that you dump the OE fan control strategy and buy the version comes with the an adjustable fan controller instead (FAL 410 or 412 for 2500 cfm, FAL 480 for 3000 cfm).

https://www.rx8club.com/assaultech-1...8/#post4942566

but unfortunately there’s no asymmetric or noise consideration nonsense going on, you can sit and overheat in peace and quiet or you can have an EF5 tornado keeping your engine temp under control; your choice.
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hufflepuff

hmm, i rather like my engine staying cool so i'll choose tornado over coolant seal failure. Thanks, Team.

CarbonRX

Hi,
I have put a S2 fan to a cheep S1 radiator. both motors are different, plus shroud is different, a mount has to be cut off and relocated to be able to mount to the radiator.
The problem is the top rad mounts don't line up to the chassis.
hope this helps.

kevink0000

A contrary view:

Don't expect miracles with the FAL fans.

Are they better than OEM, yes.

Are they much much better in this car? not really, in my experience, in Arizona street driving.

Because the problem is the radiator area, and bad airflow through it.

Better fans, and rerouting coolant hoses do not change that fact.

The very best change I made to 2 different cars, was adding a large second radiator, in parallel.

I have tried Koto, FAL, OEM s1, OEM s2, series and parallel plumbed second radiator.

By far the largest change was a second radiator.

hufflepuff

Dang dude, are you boosted and tracking it? I have had pretty good experience at circuits just using good radiator foam sealing, water pump under drive, and higher ratio of water. It's really more autocross where my OEM fans struggle to cook the car between runs without benefit of ram air at speed

TeamRX8

iTrader: (25)

well spoken

but then he’s not in Arizona, which is always your go-to about why I’m not having any issue in Texas with REW turbo, FAL 420, and Koyo S1 radiator 🤔

there are quite a few threads about the FAL fans on this forum, I’d suggest for people to do their proper due diligence.
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kevink0000

Nope, NA and on the street. Stock battery and airbox.

I just don't think 210 degree temps under power are a good thing. That means 260+ from the line at the back of the keg. No thanks.

People still wonder after all these years why these engines don't last.

kevink0000

Yep. 3% humidity and 110 degrees ambient will show cooling system weakness.

If your cooling system has sufficient capacity, even a slow fan will cool it off at low speed. You shouldn't need a hurricane to get the job done, again that shows its not the problem.

The RX8 has barely enough radiator area for a piston engine of the same power. Combine that with the noted air flow problems, and you get what you get.

I have owned and own/maintain a lot of cars/motorcycles, in Arizona. The RX8 has the least margin of any vehicle I have owned or worked on.

Spend $300-$400 on a FAL setup for an incremental or no difference at low speed, or spend $180 and an afternoon of cobbling/rigging and get better cooling at any speed.

Someday someone else will try it and see. A FAL will not drop temps under power at speed 20 degrees or more. An extra radiator will.

TeamRX8

iTrader: (25)

no, while the conditions are contributing, it’s just as I’ve been saying since the beginning; you still lack the eye and the ear to either know or perceive what is before you.

you just can’t accept that there’s something there that you of all people haven’t been able to figure out or come to understand yet. Therefore, anyone who claims otherwise must be; without exception, wrong. Anybody and everybody is wrong, but not you, that’s just not possible. Not just on this radiator issue either.

You do err; lacking comprehension on the things you believe yourself to fully understand, yet do not.
.

kevink0000

Like I said, someone else will try it someday, and see the benefits. I know you haven't, if you did, you would not argue. Its really that simple. The rest is just BS.