Background (skip if impatient)
My OEM JDM GC8 Impreza radiator got a crack in the plastic end tank. I tried radiator/gas tank putty, plastic epoxy, and high temp RTV, but nothing could contain the leak, so a replacement had to be found. I still had my old RS radiator, but the fan connectors are different and all the hose connections are different. Another used JDM Radiator would have run me about $200 shipped to my door, still with plastic end tanks. Then I was told that the 90-94 Legacy Sport Sedan radiator is exactly the same. Pics are scarce, but you can find some and the tops do look roughly the same. So I could have gone to the junkyard for a Legacy radiator, but still with the plastic end tanks. The Koyo race radiator, however, is all aluminum so no more rupturing! It's hard to look up the koyo radiator model for the JDM Impreza, but if you look it up for the Leggy sport sedan you find the model is R1819. If you google Koyo R1819 you'll find a number of shops that carry it with prices ranging from $200-$300. You'll also find, at least right now, that none of them has it in stock. I was told one month special order by one store and 2-3 months backorder by another. Luckily I found (a new) one on ebay for $263 including shipping via fed ex and insurance. A little higher than the more competitive shops but available immediately. So I bought it (mind you I've never seen the R1819 since no one has a picture of it) hoping it would fit.
Now for the install:
Here is the box it came in (I think ohoY is Japanese for radiator):
![Image]()
The packaging jorb done by Koyo:
![Image]()
And the radiator out of the box:
![Image]()
![Image]()
I thought it was going to be a 36mm core, but it's a whopping 53mm thick! That's over twice the JDM core (25mm) and 3.5 times as thick as the RS core (15mm)! Hope it fits!
The top connections all look to match OEM:
![Image]()
Although Koyo does add that hole there which is plugged by that black plastic screw. Helps to burp the radiator I suppose but I don't know if I trust a plastic screw.
So far it looks promising--very similar to the OEM:
![Image]()
The JDM fans fit perfectly as did the escape hose that runs across the top:
![Image]()
Later on I found the RHD driver's side fan electrical connector is very close to the exhaust manifold heat shield. I took a gamble and left it there, but you may want to disconnect it and zip tie it somewhere else if you're unsure.
Here's the top of it when installed (bling bling):
![Image]()
You have to take the bushings out of the top of the OEM radiator and put them into the Koyo. You have to unscrew the top plate of the OEM deal to pop them out.
And the top-down view, to see how little space is left in there:
![Image]()
The power steering cooling lines still prove to be troublesome. They are metal lines and certainly not in the mood to bend. They are used to getting around a thinner radiator but this one seems to be just too thick:
![Image]()
There you can see that between the 53mm radiator and the coolant escape hose the power steering lines just can't seem to be seated flush on the top of the radiator. If I leave them like this their little foamies contact the hood, but don't interfere with closing it. -1 on the bling factor though; if you know how to work around please let me know.
And here is all you get to see of it when the hood is closed:
![Image]()
See that majesty?
So there you go. If you have a JDM GC8 Impreza, the Koyo R1819 (Legacy 2.2L Turbo Sport Sedan) radiator WILL fit.
I suppose I'll add to the review after I run it for a while.
My OEM JDM GC8 Impreza radiator got a crack in the plastic end tank. I tried radiator/gas tank putty, plastic epoxy, and high temp RTV, but nothing could contain the leak, so a replacement had to be found. I still had my old RS radiator, but the fan connectors are different and all the hose connections are different. Another used JDM Radiator would have run me about $200 shipped to my door, still with plastic end tanks. Then I was told that the 90-94 Legacy Sport Sedan radiator is exactly the same. Pics are scarce, but you can find some and the tops do look roughly the same. So I could have gone to the junkyard for a Legacy radiator, but still with the plastic end tanks. The Koyo race radiator, however, is all aluminum so no more rupturing! It's hard to look up the koyo radiator model for the JDM Impreza, but if you look it up for the Leggy sport sedan you find the model is R1819. If you google Koyo R1819 you'll find a number of shops that carry it with prices ranging from $200-$300. You'll also find, at least right now, that none of them has it in stock. I was told one month special order by one store and 2-3 months backorder by another. Luckily I found (a new) one on ebay for $263 including shipping via fed ex and insurance. A little higher than the more competitive shops but available immediately. So I bought it (mind you I've never seen the R1819 since no one has a picture of it) hoping it would fit.
Now for the install:
Here is the box it came in (I think ohoY is Japanese for radiator):
The packaging jorb done by Koyo:
And the radiator out of the box:
I thought it was going to be a 36mm core, but it's a whopping 53mm thick! That's over twice the JDM core (25mm) and 3.5 times as thick as the RS core (15mm)! Hope it fits!
The top connections all look to match OEM:
Although Koyo does add that hole there which is plugged by that black plastic screw. Helps to burp the radiator I suppose but I don't know if I trust a plastic screw.
So far it looks promising--very similar to the OEM:
The JDM fans fit perfectly as did the escape hose that runs across the top:
Later on I found the RHD driver's side fan electrical connector is very close to the exhaust manifold heat shield. I took a gamble and left it there, but you may want to disconnect it and zip tie it somewhere else if you're unsure.
Here's the top of it when installed (bling bling):
You have to take the bushings out of the top of the OEM radiator and put them into the Koyo. You have to unscrew the top plate of the OEM deal to pop them out.
And the top-down view, to see how little space is left in there:
The power steering cooling lines still prove to be troublesome. They are metal lines and certainly not in the mood to bend. They are used to getting around a thinner radiator but this one seems to be just too thick:
There you can see that between the 53mm radiator and the coolant escape hose the power steering lines just can't seem to be seated flush on the top of the radiator. If I leave them like this their little foamies contact the hood, but don't interfere with closing it. -1 on the bling factor though; if you know how to work around please let me know.
And here is all you get to see of it when the hood is closed:
See that majesty?
So there you go. If you have a JDM GC8 Impreza, the Koyo R1819 (Legacy 2.2L Turbo Sport Sedan) radiator WILL fit.
I suppose I'll add to the review after I run it for a while.
