Hi, My radiator on a UK Honda s2000 2003 is rotten, Im not sure what radiator to replace it with?
Im on Ebay and they have a fully aluminum Rad for £300 or a Plastic similar OEM for £100.
Just not sure which one to buy.
Any Help

 

You want a Koyo aluminum radiator. Best aftermarket fit. Best longevity. Better than stock cooling capacity. Best reputation.

If you don't want the race look under hood, you can brush the polished aluminum end tank or even paint it black.

painting end tank

 

Is the giant blue and red Koyo logo visible when the radiator is mounted?

-- Chuckj

 

So far my oe replacement radiator I got on rock auto is still doing its job after 3.25 years. Koyo rad is best rad, maybe too good for a daily, although just right if you're going to do the Dakar rally.

 

I would imagine it would sit behind the AC condenser, and you wouldn’t see the radiator from the front.

 

Has anyone tested how much cooler the car runs with the Koyo?

 

The thermostat regulates the coolant temp.

The bigger radiator just improves the system's ability to regulate the coolant temp.

A radiator won't make the car run cooler. It just makes it harder to overheat.

The stock S2000's cooling system isn't stressed by any means. But the Koyo aluminum radiator doesn't have any end tanks to crack, and the volume is like 3X the stock radiator's volume. So it prevents failures and also helps with cooling capacity. So its a pretty easy choice as a replacement.

The extra cooling capacity can be calculated by getting the volume delta between the radiators. Then the efficiency of both radiators. You should be able to find the specific heat of your coolant pretty easily.

 

Not if you have an AC condenser

 

I replaced my OEM with Koyo. Works and looks great. No you can't see the Koyorad logo if you're stock. As said it's behind the AC condensor

 

The main issue is that if your radiator cools too well then your thermostat will close completely or remain partially closed hurting water pump flow rates as the thermostat acts as a bottleneck.

On the stock cooling system the thermostat is fully open at operating temp.

This is why upgrading the radiator is often paired with a low temperature thermostat. So that it opens at the lower operating temps the upgraded radiator provides.