Engine radiator OEM BMW or KOYORAD

The stock piece lasts well over a decade in my experience. That's more than enough for me for a part that fits and functions perfectly.

I run the Koyorad 38mm radiator on my NB, with just regular Prestone green concentrate and distilled water 50/50, and OEM Mazda cap and thermostat. Coolant temps stay in the 190's at all times. It very rarely gets above 200 except on the hottest summer days, usually when sitting in traffic.

I placed the thicker koyorad in there and fixed a lot of issues, together with hood vents helped me getting my drift car cool.

I have the koyorad myself, bought it used. Spend some time sealing the nose to force all air through the radiator and you'll never have an overheating issue naturally aspirated.

Koyorad. Their fit and finish is OEM level.

One of the best replacement radiators for sure but you’ll have to get an external transmission cooler for it to work as the Koyorad doesn’t have an integrated transmission cooler that autos use.

i went with a Koyorad SKU: 910-371 for my NB from Moss. I live in hot sunny florida, and took it to the track a few times. never an issue. i just drove it hard to the hardware store.

Koyorad Aluminum radiator (upgrade): $380 If you got those two parts, it’d save a bulk of the money.

OEM radiator. Replaced radiator on visit 5 (today). Bmw closed loop network is what eventually led to the radiator being checked as they’ve seen aftermarket radiators actually cool the cars too much, therefore sending the tstat fault in cold weather (this issue occurred first last winter for me, then again 5 times this winter.. all same fault code). Confidence that this is the root cause fix seems to be high so fingers crossed I won’t be updating this in a few days.

When I ordered a koyorad I didn’t get this in the box. I sent back what I got from them it was all dented and didn’t fit.