Koyo Radiator thoughts

[dlynes]

Guys,

After 15 years my OEM radiator started leaking from the bottom of the radiator.

Instead of trying to fix it, I chose to pay the $370 (shipped) and order Koyo Radiator.

Looks lot better than the original...all SS is slick.

I haven't noticed anything on the performance/cooling as I have no laser or temp to gauge it...no difference from the dash readings.

So far I have only put about 50 miles on it...

**if you ever replace a radiator, make sure your radiator bleeder valve has at least an O-ring on it...mine does not and is leaking consistently...shop I bought it from is looking into it for me.

 

[NSX1145]

We actually sell more Mishimoto that Koyo, due to the warranty coverage Mishimoto offers (unlimited lifetime, including damage coverage). Our tests have shown upwards of a 30 degree in temp reduction on many Hondas across the board. Plus, they work with any stock fan setup, as well as the aftermarket fan shrouds / slim fan kits.

 

[Honcho]

I bought my Koyo from NSX1145 and it is flawless. I noticed a slight reduction in running temp. You can tell when the thermostat opens because the needle actually drops about half a tick! At the track it was rock steady even with the Dali radiator shield in front of it. I am using the stock fan shroud and fan. I heard the Mishimoto had fitmet issues, which is why I went with Koyo. It was drop in no issues.

 

[dlynes]

Dali radiator shield

thanks, ill have to check into that! and ill check my temp too.

http://www.youtube.com/watch?v=t8HitBSFHWY

 

[Tom239]

A beefier radiator was the single best upgrade I've done for my NSX.
The OEM radiator was inadequate for long uphills in hot conditions.
I live near Death Valley, where car companies come to torture-test
their cooling and AC systems. I've seen dealer plates and camouflaged
body panels there in the summer.

Nice to hear the Koyo is a good option. I got a PWR-Performance
radiator back in 2008 and it's been great, but it's since been discontinued.

Having an oil temperature gauge has been instructive as well.
Oil temperature varies with conditions even when the coolant
temperature is steady at 3/8 on the stock instrument panel gauge.

 

[Stephen@NCAutoUSA]

I got a koyo. I was cross shopping between the Mish and Koyo and bought the Koyo on the fact that a few threads revealed slight fitment issues that I couldn't deal with when changing it in a parking lot...

 

[BATMANs]

I still have my OEM radiator after 115k~ miles and still going strong.

I've used Koyo in the FD and really loved it.

There was a VERY remarkable drop in water temps and the ability to cool.

I would certainly do Koyo for the NSX should the time come.

 

[Hrant]

Point of clarification if I may ..... when claims are made there was difference when changing from the "old" OEM to the new brand radiator, what control measure was used to separate the variable fact that the "old" OEM was by definition of it being old and used for years definitely not going to be as efficient as comparing say a "new OEM" vs the new brand? Just asking ...

 

[BATMANs]

good point and i knew that would surface up.

In my case with the FD there were no visible corrosion, clogging, etc. in the OEM radiator when we took it out and cut it across the cooling fins to inspect.

I made a habit of changing all of my fluids every 10k miles:

brake/clutch (same system)
oil
tranny
diff
coolant
power steering

I was driving the FD VERY hard. abusing it. trying to break things so I can make it better.

 

[Tom239]

Point of clarification if I may ..... when claims are made there was difference when changing from the "old" OEM to the new brand radiator, what control measure was used to separate the variable fact that the "old" OEM was by definition of it being old and used for years definitely not going to be as efficient as comparing say a "new OEM" vs the new brand? Just asking ...

Good point. In my case--

I got my NSX with about 33,000 miles and the OEM radiator was
always inadequate for long uphills in the summer. By inadequate
I mean the coolant temperature would rise enough that you'd feel
bad about subjecting the engine to it: 6/8 or 7/8 on the gauge
depending on the day and steepness of grade.

I swapped the radiator at 71,000 miles and the original had the
bugs and some bent fins you'd expect from that age. But the
inside was really clean; I always used Honda premixed coolant.
I cut the old one open to inspect it because I was curious.

The PWR radiator is about 50% thicker than the OEM.
In demanding conditions I saw substantial improvement.
Long uphills in the summer that used to send the coolant
temp gauge to 7/8 with AC off I can now take with the AC
on and the gauge will stay at 3/8.

 

[davidf]

Price on the Koyo please?

We actually sell more Mishimoto that Koyo, due to the warranty coverage Mishimoto offers (unlimited lifetime, including damage coverage). Our tests have shown upwards of a 30 degree in temp reduction on many Hondas across the board. Plus, they work with any stock fan setup, as well as the aftermarket fan shrouds / slim fan kits.

 

[dlynes]

159k until started leaking