Best Radiator for a Miata?

Title says it all. My 99 Miata needs a radiator, and I'd like to avoid buying junk. I figure with the popularity of this car here, its the best place to find out what I should get. So, who makes the best radiator for a Miata?

There hasn't been one answer afaik. It also depends a lot on what you use the car for and where you are. Even some of the "cheaper" brand radiators have been working fine for local time attack/miata challenge guys (like the CXracing stuff)

As said, depends on what you use the car for. Some like the slightly bigger all aluminum for heavy duty use, like track. I put a Koyo stock one in my 99 a few years ago and have had no issues with it. Shop around for price. I got mine from the Radiator Shop EBay page for reasonable. They were a good to deal with too. Went out of their way to make sure I got what I needed.

I picked up my Mishimoto on Amazon. It was inexpensive-ish and survived freezing solid. I'd buy another for sure.

This is a DD and autocrosser. Although price is a concern, I'm more concerned with quality. I'm tired of junk, made in China pieces of drek, and want to make sure whatever I buy is going to last.

Are you looking for stock replacement or a performance option?

In reply to Swank Force One:

It depends. Do I need a performance radiator? The car is stock now, but may get some mild mods later. I do want a direct fit.

bravenrace wrote: In reply to Swank Force One: It depends. Do I need a performance radiator? The car is stock now, but may get some mild mods later. I do want a direct fit.

For DD/autox, i don't think you "need" a performance radiator. You need one with forced induction and i'd say you need one for track work.

For street/autox, nah.

There's an $80-$100 stock replacement made by Koyo on Amazon that is the miata.net darling that i'd suggest. I don't have the part number in front of me at the moment, though, sorry.

In reply to Swank Force One:

Thanks. What would you suggest if I did want a performance radiator?

bravenrace wrote: In reply to Swank Force One: Thanks. What would you suggest if I did want a performance radiator?

That's a much harder question. I've used the Koyo 37 and 55s, Mishimoto, and ebay 55mm. Never had an issue with any of them. FM and Trackspeed both have awesome crossflows as well. 949Racing is working on a crossflow of their own as well.

Current car will probably either get the new Koyo "Hyper V" or a CSF 42mm.

In reply to Swank Force One:

Do the numbers refer to the thickness of the core? And do any of these bolt in without mods?

Yes, sorry. The numbers, where given, are the core thickness in millimeters.

They all bolted in without any modifications that i've used. Believe the Trackspeed crossflow might need a different upper radiator hose due to outlet location.

Right or wrong I have an aluminum 3 core civic half rad to go in my jrsc car with an air to air i/c to go along side it.Coolant reroute as well at the same time.

This replaces a stock rad and water to air set-up.

kevlarcorolla wrote: Right or wrong I have an aluminum 3 core civic half rad to go in my jrsc car with an air to air i/c to go along side it.Coolant reroute as well at the same time. This replaces a stock rad and water to air set-up.

Interested to see how this works for you. I've only seen this done twice, both times on dedicated autocross cars.

Miatas are tough little buggers to keep cool, cutting your frontal area in half isn't generally considered a good idea.

Best radiator on the market - backed up by extensive dyno testing and a win at the Thunderhill 25 hour - is the FM cross flow. Made in the US by Griffin. But it's not as cheap as the Chinese eBay stuff. It also uses a more efficient core, so it doesn't need to be as thick as the stuff with lesser core designs. In fact, efficiency goes down as core thickness goes up.

In our testing, stock radiators outperformed some of the aftermarket stuff.

The 949 rad is a knockoff of the FM part.

If you're not heavily modified (naturally aspirated, not running in a pack of cars) any healthy radiator will probably do the trick since you're not really loading up the cooling system very much.

Yes mine ran way hot with stock rad and dual fans + autox 2 drivers and maybe 80 degrees.This setup came off a big boost cold side charged ssm car,says stayed steady temp with 2 drivers and 110 degrees.

Not having an additional heat exchanger for my w2a in front of the rad is a bonus for sure.

kevlarcorolla wrote: Yes mine ran way hot with stock rad and dual fans + autox 2 drivers and maybe 80 degrees.This setup came off a big boost cold side charged ssm car,says stayed steady temp with 2 drivers and 110 degrees. Not having an additional heat exchanger for my w2a in front of the rad is a bonus for sure.

Oh, you bought David's setup?

Swank Force One wrote:

bravenrace wrote: In reply to Swank Force One: Thanks. What would you suggest if I did want a performance radiator?

That's a much harder question. I've used the Koyo 37 and 55s, Mishimoto, and ebay 55mm. Never had an issue with any of them. FM and Trackspeed both have awesome crossflows as well. 949Racing is working on a crossflow of their own as well. Current car will probably either get the new Koyo "Hyper V" or a CSF 42mm.

Do the Koyo radiators have plastic tanks like the OEM? They don't say on their website.

The cheap oem replacement one does. The others don't.

I replaced mine with the Koyo Amazon OEM special mentioned above. It's black and plastic and works great. If you autocross, make sure an aftermarket rad is legal for your class. I don't think they are until Street Prepared.

Swank Force One wrote:

kevlarcorolla wrote: Yes mine ran way hot with stock rad and dual fans + autox 2 drivers and maybe 80 degrees.This setup came off a big boost cold side charged ssm car,says stayed steady temp with 2 drivers and 110 degrees. Not having an additional heat exchanger for my w2a in front of the rad is a bonus for sure.

Oh, you bought David's setup?

Since I suck with names and this was last fall I "think" the name was David,he was parting out everything and I grabbed just the rad, I/c and reroute.Up here in Ontario the temps rarely get into the 90's so I think it should be ok with my vented hood and I'll do a decent sealed shroud on the cold side as well.