RonKMiller

Well, the only thing that sucks is the plastic end tanks, other than that I think it's a pretty damn good design and is really quite efficient. Amazingly light. Considering it was designed in 1989...only...gulp...14 years ago!

I can't believe that even freakin' Mercedes is STILL using plastic end tanks. Tell me it isn't a communist plot...

FormerPorscheGuy

Its a single row radiator that barley offers enough capacity for the car its installed in. Coolant capacity in the stock form is inadequate for these cars. The stock fans come on at 230, the airflow into the radiator is not the best, and the radiators has very little surface area, and last but not least the plastic stock AST.

The coolant system was a horrible design that did nothing for the life expectancy of the car or its ability to stay cool.

The plastic end tanks are prone to cracking because of the heat that is generated in the close quarters of the engine bay.

Increasing the coolant capacity and surface area of your radiator is a sure fire way to keep your cars temperatures down.

The infidel reds will have their hands in everything soon if we aren't careful.................

adam c

iTrader: (2)

Actually, the cooling capacity of the stock radiator is good enough for just about anything except road racing. Once the car is in motion, it cools just fine. The problem lies in the crummy plastic end tanks, which fail more often that an all metal design. Sure, more capacity is better, but the stock capacity generally is good enough.

Senna

Ok, forgive my ignorance please. When upgrading to an aftermarket radiator do the plastic end tanks come out too? Didn't think it was an issue until reading all the discussion here re: end tanks.

Thanks.

DamonB

Yes. The endtanks are a permanent part of the radiator. The stock one has plastic tanks, an aluminum one has aluminum tanks.

Senna

Thanks DamonB.

Kento

Although I feel the stock radiator is fine for street driven FDs, you should replace it with a new stocker at the very least. Here's why:

https://www.rx7club.com/showthread.p...diator+upgrade

I went for one of the much-hyped aluminum radiators (PWR) because of its additional surface area and capacity, as well as the peace of mind that comes with no plastic end tanks. It has proven to be a solid investment, with no cooling problems whatsoever, despite additional hp (and heat) from engine upgrades.

MrRx

iTrader: (1)

Boys Boys chill, everyone does something differently.

I personally would have done it from the bottem, Besides gives you a chance to check up on everything you cant see from the top

MrRx

iTrader: (1)

Yeah, so forget about my last post...I dident notice i wasnt at the last page when i was commenting

clayne

Problem is, if one is upgrading their radiator, they should be making _cooling_ the priority.

The Koyo fitment issues are nothing but exaggerated annoyances when putting the radiator in.

1. Bend the A/C and/or PS lines around for fitment
2. Bend the radiator supports down.
3. Trim the plastic guard that is attached to the front black plastic grill but extends to the front of the radiator neck.

clayne

Oh yea. Do it from the top. Taking out the IC and Intake are really not that hard once you've done it a couple times.

clayne

Ron,

The stock radiator doesn't hold a candle to an aftermarket one.

JeffShoots

"Easiest to install Radiator"

My Jeep CJ has only 4 bolts and 2 hose clamps

sirjury

tip of the day on rad install. use cardboard and tape it to the front and back of radiator to prevent damaging the fins. remove cardboard after intall is complete. i let the dealer "try" to install my mazdacomp radiator. they damaged over 20% of the fins gave up and put in their "stock" radiator. i promptly took the car home removed and intalled the mazdacomp rad in 1.5 hours. not including the time spent with a pick (3.5 hours) straightening all the bent fins.
moral of the story
i hate dealers
use cardboard with rads and ac condensors

clayne

Yes, definitely do that. I didn't and you can see where the fan relay plugs bent some fins down that were obviously a hassle to bend back.

sandersja

I just did this job this weekend so it is fresh in my mind - and my hands are still battered. Everything on these cars is tight.

I was installing a MazdaComp radiator and was only able to do it from below. If you have the stock or JDM intercooler intake ducting then there is not enough room to drop it in from above. Even it it is not there, you will bang into the AC lines.

Bottom line, the easiest way is to do it in two chunks - the fan assembly first, then the radiator. I have the second oil cooler and these lines make it too tight and damaging to the fins to try for force both at the same time. I inserted the fans and suspended them by string while I inserted the radiator. They can then be bolted together and the assembly adjusted up to the mount points.

Kento

Quick tip to avoid damage to the radiator cooling fins during installation: tape some cardboard to the radiator face to protect those fragile cooling fins while you're moving the rad around during install. Then just pull off the tape and slide the cardboard out when the rad is bolted up.

Herblenny

iTrader: (13)

Sorry to bring this back..

I was the one who helped Tim (academytim) with his radiator.. Damn.. I thought it was pretty good.. I have an oil extraction pump that I bought couple of years ago.. that I hooked up in between the ast line and radiator.. Pump and I could change my radiator fluid with out lifting the car or draining from the bottom (2-4 minutes to extract all fluids).. Also change my oil the same way (5-10 minutes).. Great at the track and also save me time on jacking the car, etc..
Those who seen it, think its great!

Far as changing the radiator.. I have done few for friends and on my car.. and I believe going from the top is faster and easier.. I don't have to mess with unbolting 10+ rusted bolts for the underbelly and stuff.

Also, far as radiator, I think fluidyne is good... need little work to fit.. but PWR seems to be a better fit and better construction.. Koyo for size and price, is great.. but bigger always don't mean better.. I know ton of stock radiator users running 350+ WRHPs.. I'm scared that top plastic parts cracking..

RiON

aanyone have pics how to mount the stock radiator after getting the single t78 turbo kit?

Herblenny

iTrader: (13)

Depend on what kind of Intercooler..

Most t78's I've seen run fmic..

jspecracer7

Wow, I couldn't imagine doing the job from the bottom. Took me like an hour to do it from the top...smoking' and jokin' the whole time.

FWIW, I monitored my water temps with the stock radiator very closely. They cooled REALLY well for stock. I think the problem with the cooling system is the FANS not coming on early enough.

Herblenny

iTrader: (13)

I can't imagine either..

FormerPorscheGuy

I agree, the Miata switch has been one of the best mods that I have done.

jspecracer7

I had a friend with datalogit so I had him lower my water temps that way. He actually rigged up a Honda temp switch when he was running a knightsports ECU. Best thing in the world for an FD really.

xstacy7

I think (just my opinion here...no rock throwing) that the reason people have fitment issues (this was my deal) with the koyo is that a slight fender bender can offset where it goes by just maybe a 1/4 of an inch...causing major headaches and cursing every 5 seconds. This was my deal with the koyo. It didn't sit far enough down because it was messed up from a wreck (previous owner) and it caused the intercooler duct to sit up higher and everything else basically was fudged. Just my experience with it

Jack