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Hey guys, Had my radiator just spring a major leak surprisingly..Idk what happened, I was driving and all of the sudden temps started to rise, pulled off immediately, and looked, coolant pooling on the floor, trail of coolant behind the car. I pull off the airbox and ducting and battery/tray, The top hose is fine, the bottom hose is fine, I cant find any hoses ruptured. If I pour water in through the filler neck it starts leaking from some point in the radiator i'm assuming. I can pour into the AST it doesnt leak, I'm assuming something happened to the radiator.
Anyway..I'd heard the Fluidyne radiators are the best fit. I may honestly just go stock or mazda comp, since, mazda comp must fit well, right? Well I logged onto MazdaMotorsports, and the only competition radiators they are showing are: Koyo Rad Notes: R1443 53MM CORE and Koyo Rad Notes: HH060644N DUAL PASS. Are mazda comp radiators Koyo rads, or is that just what mazda motorsports sells as a competition radiator? I'm looking for the best fitment, so i'm assuming I should go stock or fluidyne?
Unless Fluidyne updated their design, it does not fit well with the M2 intake boxes. I've always had to modify the M2 box the upper hose hits the bottom of the box. Otherwise it has been problem free for many years.
From research Mazda comp radiators were made by Performance Aluminum Radiators and Custom Aluminum Radiators and last time I talked to them, they can still make them. Seeing pictures of the Mazda comp ones, they included extra metal on the side to seal off the area and send air through the core. This is great if using a stock style intake but will not work with an m2 style box.
Interesting the popular N Flow is 48mm while the one you listed R1443 is 53mm core.
Ron Davis made mazda comp radiators. You can still get them made new, and they answer the phone. A little spendy, but a reputation for quality.
The Koyo's fit with a little work and a lot of people swear by them. Fluidynes fit good. Don't hear any complaints from any of these, once they're installed.
That is my dilemma, I am trying to find a truly drop in, no modification necessary radiator. I don't want to cut up the bottom of my airbox.I suppose it will be a stock one from mazda motorsports. Are those factory radiators copper or aluminum?
The stock ones are an aluminum core with plastic end tanks. The ron-davis/mazda-comp radiator fits like stock and works with the m2 intake, fwiw. I've run it with both.
Unless Fluidyne updated their design, it does not fit well with the M2 intake boxes. I've always had to modify the M2 box the upper hose hits the bottom of the box. Otherwise it has been problem free for many years.
Did you remove the hose support bracket? Even with the stock radiator you should remove that to install the m2 intake.
My lack of sleep today is getting to me. Just to clarify, my car is entirely stock. Stock air intake, air boxes, etc.
Also, I'm clueless as to what could have happened to cause the car to start pouring coolant onto the ground. I literally removed the intake, air box, and battery and battery tray and looked as best I could. The upper coolant hose is fine, the bottom one feels fine as well. if I pour water into the AST it does not pour out. If i pour water into the filler next, it pours out the bottom faster than I can put it in. But the bottom rad hose is not leaking.
So if the filler neck feeds the upper rad hose, and the lower rad hose isnt leaking, but water is pouring out inbetween the two, could that mean something damaged my radiator? the rubber/foam insulation on the undertray that meets the bottom of the rad is soaked.
Last edited by SwappedNA; Oct 8, 2019 at 12:34 AM.
The "Fluidyne fits the best" is an old wives' tale. Koyo fits great, Banzai Racing recently did a post showing how to install it and it installs very cleanly. I would get the Koyo - very good price, fits great, works great, and very well built and designed.
I would probably just get the plain Koyo and not the N-flow, on a near-stock car that would be all you need.
Have you pulled the under tray off and looked for the leak? If it's just pouring out the bottom it should be pretty easy to find. Gotta get underneath the car.
The "Fluidyne fits the best" is an old wives' tale. Koyo fits great, Banzai Racing recently did a post showing how to install it and it installs very cleanly. I would get the Koyo - very good price, fits great, works great, and very well built and designed.
I would probably just get the plain Koyo and not the N-flow, on a near-stock car that would be all you need.
Have you pulled the under tray off and looked for the leak? If it's just pouring out the bottom it should be pretty easy to find. Gotta get underneath the car.
Dale
How much modification is needed for the Koyo, though, on a stock car? Any at all?
The "Fluidyne fits the best" is an old wives' tale. Koyo fits great, Banzai Racing recently did a post showing how to install it and it installs very cleanly. I would get the Koyo - very good price, fits great, works great, and very well built and designed.
Dale
Banzai's post / process aside, and from personal experience, the Fluidyne is the easiest to install and just plain fits w/o having that knowledge of tweaks to make the Koyo fit easier.
Stated differently, it's more idiot proof - which is helpful for idiots like me.
Banzai's post / process aside, and from personal experience, the Fluidyne is the easiest to install and just plain fits w/o having that knowledge of tweaks to make the Koyo fit easier.
Stated differently, it's more idiot proof - which is helpful for idiots like me.
Only problems I have seen are the Fluidyne does not cool as well as the Koyo, it is considerable thinner (38mm vs 48mm), the drain fails after a few uses and the integrated mount brackets are terrible if a front mount is installed. It is also nearly twice the price of an R series.
Besides that it is a good radiator
Last edited by Banzai-Racing; Oct 8, 2019 at 02:02 PM.
Only problems I have seen are the Fluidyne does not cool as well as the Koyo, it is considerable thinner (38mm vs 48mm), the drain fails after a few uses and the integrated mount brackets are terrible if a front mount is installed. It is also nearly twice the price of an R series.
Besides that it is a good radiator
LOL. Agree with most of that.
Thinner yes.
My street driven operating temps were similar with both rads on the same car back in the day when i 'upgraded' to a Koyo. YMMV of course. If you're using a FMIC, then a Koyo is definitely the better option.
I never used the drain. Good to know.
Did you remove the hose support bracket? Even with the stock radiator you should remove that to install the m2 intake.
I did everything to get the fluidyne to fit with the m2 box. Disclaimer is this radiator is from ~2008 and I heard rumblings a long while back they may have revised the angle of the upper neck to not come up so high? It was easy enough to cut and bend the bottom of the m2 intake box to get it to fit without smashing the hose.
Looks like the Koyo N flow is the winner if using a M2 style intake, otherwise the Ron Davis looks great as well.
Well, I went out and looked at the car after getting it towed back from where the incident happened, I filled it with water with the airbox, piping, and battery & trey removed, and I could not see any hoses leaking. Used one of those corded cameras and snooped around the back and underside and saw water pooling on one side of the radiator before dripping down. I happened to move the fan blade, and saw this: I wonder what could have caused that.
The thing you should be deleting anyway? I see no problem with that...
26mm core for $50 more than an 48mm R series Koyo. You can put whatever you want in your car, I know what I have been installing for the last 20 years.
Mishimoto makes an oem-ish radiator. Imagine a stock one with aluminum end tanks. I cant comment on fitment but I'm sure its fine.
The Miata version of that rad sucks. The nipple for the overflow threads in instead of being welded on like other rads. The threads loosen up and cause the coolant to leak and air in the system and an overheated engine if it happens too quickly - as it did to my friend. I just can't forgive that...
The Koyo is the best bang for the buck and is a known performer. The Fluidyne is great too - just more expensive and the issues that Banzai mentioned
Well, I sourced a Koyo regular radiator. Installed it today, I've noticed that for some reason (this is only after a warm up and 20 mile drive) that my temps are about 14~F cooler cruising, yet when I stop, the temp seem like they climb faster than they did before. The fan will kick on at 194 according to my AEM temp gauge, and will drop the temps down to the low 180's, and it repeats, so it's stable. It just seems like the temp gets up to 194 faster than before?
Also, do you have to flip both brackets or just the passengers side condenser bracket? I'm still having fitment issues on the drivers side having it slide onto that stud up top.
You may still have some air in the system if you just swapped out the radiator. It also could be you're not running AC which runs the fans continuously.
As far as the install did you follow Banzai Racing's writeup?
