Engine radiator Koyo or Nissens

just replaced one and aside from slight issues with the drain plug alignment that needed some finessing, seemed fine and held pressure.

I would recommend the koyo radiator with stock fans. It’s been 3 years with mine zero issues it’ll run cool in 120 desert.

I would recommend a full aluminum koyo radiator. There are pricy but they fit like OEM and use the OEM fans. 2 years later with 15k and no issues.

Koyo has better fitment than Mishimoto tho, I think that's more important as they both have good warranty. One thing to note is the only radiator Koyo has for the DE that is OEM design is the larger one, the smaller one it the cross flow, which is better performance wise but puts the radiator cap on the passenger side. That's the one I currently have.

Im in AZ, and I was hitting up in the 225+ coolant after a Grimmspeed FMIC, and so I went ahead and upgraded to a koyo. Now I’m staying around 196-206 depending on situations. Highest I’ve seen is 208 or so.

I have a Koyo radiator on my 2019 and am really impressed with it. You get a thicker core and all aluminum construction so you don't have to deal with the metal/plastic interface of the OEM one that can crack/leak over time.

I've been using an OEM style Koyo Radiator for the last 10 years on a clutch fan. Multiple track days and never any overheating issues.

I opted for a stock replacement Koyo with the plastic end tanks again. It'll get you buy for another 10-15 years and 100k miles.

me and some E39 buds here in the Netherlands have great experience with nissens. It's a pretty good package all around and had a copper core instead of alu.

Roughly 12 months ago, I upgraded the radiator on my 2000 Series 8 (~65,000km/40,000mi) to a Koyo R1443N 48mm N-Flow. The coolant seals blew because the radiator's design allowed air to accumulate, creating hot-spots and leading to seal failure. My water temps never exceeded 90C. After a rebuild, a valve was installed on the radiator elbow, making it quicker to bleed the system, and water temps are now around 77C, about 10C cooler than before. The Koyo radiator's design prevented proper bleeding of the coolant system, causing seal failure.