I've got a few questions for anybody running a Koyo radiator in a S4.

1. How well does it fit the stock mounts? Did you have to cut anything to make it work?
2. Are there any catches or issues with using the stock fan shroud with it? I do _Not_ want an electric fan.
3. My stock level sensor has an overflow hose on it. How hard is it to find one without?

If anybody's got pictures of one mounted that would be sweet.

The plastic ends on my stocker cracked and the aftermarket rad i bought to replace it doesnt fit the brackets. I'd have to cut 2 small L-shaped brackets off the car or notch the brackets on the radiator to make it fit.

I'm considering just taking this one back and ordering a Koyo. I'd rather have aluminum than copper any day. Less corrosion.

PS: Yes i have, and am searching. There's a lot of fluff to sort out.

 

Sorry i wish i could help i do have the koyo radiator but i also have a S5 and a E-fan

 

Excellent post. I hope I can be this informative some day.

 

i have one on my s4 and its a direct drop in replacement. put the stock brackets on and put it in.

 

Do you know which model number Koyo you have? The one i'm looking at is R0181

 

i have the s4 model in my s4 and the s5 model in my s5...both are the same deal.

 

-Bolts right in,nomods needed
-Fan shroud fits perfectly
-Why find one without?

Spec.

 

my s4 koyo fit perfectly, with stock fan shroud and all. Runs a lot cooler during hard runs, mountain drives, etc.. ive never seen the temp get above 1/4th with the koyo

 

Thats not good. Car should operate around 175 to 190F.

Do you have an OEM thermostat?

Spec.

 

all the hoses plug right in it bolts right up i had it on mine and mine is for sale if inerested pm me

 

On the s4 gauge, 1/4 up is around 180ish. S5 gauge is different.

 

I have one on my S4 and it fits pretty well. As the others have said you will need to use the mounting brackets from your stock radiator. The Koyo does sit a bit further back due to the added thickness of the core. I also had to move/stretch the stock fan shroud a bit when installing mine, but overall the fitment is about as close to perfect as you can get. Also, you may want to replace the drain plug that comes with the Koyo as they tend to break easily.

 

^^I ended up using thread sealant on both plugs that come with the radiator. IT is an easy install. I also use the fan shroud and have no problems. I also had to cap off the peice coming from the top cap. I just used a rubber cap and zip ties. IF I can I'll post pics tonight when I'm at home.

 

yeah i not sure if you all got the the 2wall or 3wall but my koyo was really thick and i had to take my stock mounts and rebend them to fit my koyo. also i threw out my fan shroud, but i do live in north WA so it never really all that hot here. it does run pretty cool tho

 

The composite top and bottem on mine broke too. So I got the koyo (s4 n/a).

Took off the brackets on the left and right side of the stock radiator, and put them on the Koyo. Perfect match. Everything went together like butter. Only I broke that little connection at the bottem... Oh well...

 

Notcie the red cap on the radiator.

 

Thanks a lot for all the info guys! I placed my order today, hopefully i'll have the new rad thursday and get this baby back on the road!


Congratulations! I wish all of your hopes and dreams come true as easily as this one did

 

do all the S4 koyo rads come with the cap and overflow spout on the top of the rad?

 

Everything stock fit perfectly on my S5 except the fan shroud. It fits, but it takes a bit of effort to get it screwed down.

 

the rad doesn't come with a cap, but it does have a overflow nipple under the cap area

 

Not sure where you fit into this, but I appreciate your concern.

 

lol so I got mine under a week after I ordered it. I dont have spacers or anything for the fanshroud to bracket assembly, so I zip-tied it