Much cooler now !

This is perhaps not the most necessary upgrade one would embark on and many of you will probably only undertake such an upgrade much later on in your "tuning careers" but for me the time is now ! A brand new KOYO racing radiator !

(click on images below to enlarge them)



It is a KOYO Type-M racing aluminium radiator with a 36mm core consisting of 2 layers made specifically to an exact fit for a DC5. The OEM radiator was a DENSO 10mm single layer which just wasn't enough! Makes you wonder why a Type-R (and all Hondas actually) would have such a thin radiator but the answer isn't so difficult to come up with ... if Honda had given us all the best tuning parts in the world/Japan the car would have cost almost double of its original price. So they compromised.

To supplement this radiator I also ordered a SPOON low temperature thermostat and a fan switch to aid in cooling of this new system and some SAMCO radiator hoses.



As always the guys at SEEKER did the whole installation.

Bumper is off, coolant is being drained..


Some places are tough to get to !


New radiator fully unpacked ...


Old radiator is out !


Look how thin the old radiator is !


1cm to be precise !


New thermostat is somewhere in there with the shiny blue hoses


KOYO radiator is in !


Time to bolt up what was unbolted ...


New coolant goes in ...


Pressurizing the system ...


All looking good !


These are brighter than I thought they'd be !


The intake cover goes back on ...


Getting the engine working so we can check all the components ...


Last look at it before it disappears behind the front bumper housing


And we're done !


So let's talk about the differences !

With the OEM radiator, water temperatures during city driving ranged anywhere between 82C - 100C (average in low-mid 90s) depending on weather / traffic conditions. The cooling fan usually kicked in around 93C-97C if the car was stationary for longer than usual. High speed highway and circuit driving would yield around 85C-90C.

With the KOYO radiator (and this is a pleasant surprise !), city driving range seems to be between 78C-85C (average of 80C) and the fan kicks in around 80C. So far I have been only able to do high speed highway driving and the temperature stayed at a constant of 75C !!! To add to this the oil temperature stayed below 90C whereas with the OEM radiator it was 95C-ish.

So there is no doubt cooling is now greatly improved and finally I can relax about the engine heating up too much, hopefully my next circuit visit confirms that the oil temperatures are now also under control and thirdly this K20A engine can now work at its optimum performance with such a well cooled system.