I am replacing my existing radiator and want to know what would be a better choice for a stock application? I like that the koyo's adds and extra 30% coolant capacity but what negative affects could these radiators do? Maybe not warm up to operating temperature or take a lot longer to warm up? Also ,are they a direct fit? i don't want to cut anything to install. Anyone out there have a good recommendation here, maybe someone that has a koyo comment on this?? The one i am looking at is from prostreetonline for approx 330$. 1991 rx7 n/a

 

no downsides to getting a koyo for your fc. no cutting involved either. Just take your old side straps off your old radiator and put them into the pre drilled holes for the new one. Also you will have to cut about an inch or so off the rad hoses. Also if you get the radiator from www.absoluteradiator.com it automatically comes with the fan shroud mounting kit (free of charge).

 

No negatives except the price difference. Stock radiators have plastic endtanks that will crack and burst coolant everywhere. A koyo is pretty much a one time investment. Also I didnt have to cut any of my radiator hoses, but did have to bend the stock radiator brackets and grind the holes larger. Mounted the stock shroud fine with a mounting kit.

 

I honestly don't think there're any downsides to an aluminum radiator. Cooling is one of the best upgrades you can do besides brakes and tires. It'll last and cool your car better. Check out www.absoluteradiator.com and contact Koyo so this way you can be better informed. Good luck.

 

dont worry about warming up , if you can get a an e-fan just set it up with a thermoswitch

 

thanks guys im going with the koyo. and ill check absoluteradiator too thanks.

 

i run a koyo on my n/a w/o any problems and i have them for sale for $315 shipped as well- chris @ spd racing

 

I know I know kinda Off topic, but....


Well, after messing and messing with my crappy leaking stock rad., I brought the car to my mechanic to have it pressure tested.
I've tried all the tests I can in my driveway and was fearing o-ring problems.He pressure tested it and found a hairline crack along the top of the plastic tank. He said it needed to be brought to high pressure before any signs of leaks.( what pressure?)

But anyways, I just ordered the Koyo from Absolute. They were very pleasant on the phone, and the Rad will ship tomorrow. Should be in the car late next week!

In a week or two I'l fianally be able to get the car to Moroso to see what it (and my reactions) can do!

|M|

 

My Koyo was WAY cheaper than what Mazda wanted for an OEM radiator and of course it was dual pass unlike the single pass stocker.
This ones a no brainer, go for it.

 

Kewl... when are you planning on taking you car to moroso??? my school gets out on the 28 so I should be back in Ft. Laud... it would be nice to have some more rx7s riding out there together...

 

is absoluteradiator a reputable company? they have good prices and their area code shows they're close to my house, but they haven't responded to my emails so i had second thoughts

 

anyone know if an S4 koyo can be used on an S5 to eliminate that retarded filler neck?

 

Then you'll have no filler neck

 

unless you convert to s4 wp and housing.

 

And you can have a thermoswitch for your electric fan too!

 

at what HP would you recommend switching to an aftermarket radiator like koyo from the stock radiator?

 

probly like 500 lol, i think the stock radiator is pretty efficient

 

I think kabooski (guy who hit 520whp) is still running stock radiator. or atleast he did on the dyno vid i saw where he hit 520.

-Andrew

 

excellent, then I won't need to spend any money on upgrading cooling for my minimal mods. =)

 

For a street car, the stock radiator is sufficient. Try taking an FC on a road course with a FMIC and stock radiator and overheating is almost guaranteed

 

For a street car, the stock radiator is sufficient. Try taking an FC on a road course with a FMIC and stock radiator and overheating is almost guaranteed

 

Actually you can take it one further, the stock radiator is insufficient for a 100% stock TII on a road course. You can get away with it if ambient temps are low, say 65 degrees and below. Actually you can get away with it with 90 degree temps, but it's quiet clearly not good for the car when your temp gauge is running @ 90%+.

 

WEll I have no plans yet to go 1/4 Mi.
Just stoked that now I can actually go out and play with the rest of the guys.
End of april or early may, we should get a bunch of 7's up there(8's too!)
I know I 've talked to a few other guys about going up there, only my car hasn't been in good enough (leaky rad) to do it.

I'll search around, I think there area few regulars at moroso that are on this board.

|M|

 

yes they are! Great company and very good customer service! the fan shroud mounting kit comes free with thier radiator as well at the price is great!