brass costs about 3 times as much as aluminum. copper is roughly 4-5 times as much as aluminum.

the thermal conductivity is better but the prices will reflect the difference, in most cases aluminum is sufficient as you can make a radiator 25% deeper, as efficient and for half the price.

 

The last time I looked (4 years ago) koyos where going for over 300 bucks but I got my copper radiator for 235. Maybe I got a steal?

My copper rad cools like a beast.

 

nope, it just goes to show how much you pay for a name is all.

you can buy even namebrand cores for about $75, so they're charging $225-$325 to weld up some $10 sheet metal together. you could pay to have a full radiator way beefier fabricated for less than a koyo costs, but the problem is dimensions and whether it will fit right or not.

when i had domestic muscle cars you could get a radiator twice as big as these for about a buck fifty and they were made in the USA.. i know shipping hurts but not that much.

 

Looking on rockauto.com a brass/copper radiator for a 88 Rx7 is $87.00 more than one for my wifes Mazda Tribute( rebadged Ford escape) from the same manufacturer. It is bigger than the Rx7 one but has an aluminum core and plastic tanks. It is $96.79. If they made these aluminum cored ones for the Rx7 I wonder if they would be less than $100.00 too?

 

at this point it's about supply and demand, while they may be able to fly them off the shelf for under $100 on a car that is widely on the street the RX7 is 25 years old and the parts just don't move that much. so you're paying a stocking fee.

 

This makes me wonder if that as long as my current brass/copper one is not leaking if it is just a waste of money to replace it?

 

yes.

in my experience the copper/brass radiators work as well if not better than aluminum parts and they fail less often. the only real problem is no one makes them in performance upgrade sizes, so they're designed to simply meet OE specifications. so if your car doesn't need more cooling, it's fine.

 

Yeah, I figure there were way more Escape/Tributes sold than 2nd gen Rx7's.

 

It didn't before it locked up. Will have a streetport when it runs again.

Sounds like a brass/copper one may be a viable option for the original poster since he only wants an OE sized one. Mine is a CSF and the fan shroud fit fine before I went to the E-fan. Don't know how the ones on rock auto for the rx7 fit but the ones I've bought off there for 3 other cars fit fine.

 

the aluminum is stronger than copper so they can make the rows longer so they have more surface area... they can also make them thicker because it cools better deeper into the radiator because it has less rows.

a 2 row aluminum might be the same size as a 4 row copper...

 

there was probably actually more FCs sold than those cars, except as of this moment there is probably at least 100 of those cars on the road to every FC still moving under its own power.

 

That's because those cars DO baby and DON'T drift.

 

Did some digging and found some stats. There were 516,375 Escapes sold in the U.S. from 2002-2005 and 172,340 of it's sister the Mazda Tribute for a total of 688,715. According to goodcarbadcar.net. The FC not so easy to find but what I could come up with from this thread
https://www.rx7club.com/2nd-generati...umbers-615331/

was between 155,380 and 161,386 from1986 to 1992. I'd agree though there probably is 100 of them on the road for every one FC moving under it's own power.

 

Now this sounds like a winner that would meets my requirements. What brands are made out of copper/brass materials? I know koyo is out of the question. I am thinking godspeed or mazdaspeed? At this point I am simply looking to get the radiator with little to no modification, meaning all the mounting points line up to the oem specifications. It is tough to gauge which options to go with seeing the amount of mixed reviews I am getting here. I suppose I would just have to see the results myself.

 

You can go here RockAuto Parts Catalog and navigate through their catalog.Looks like all the have are the brass/copper ones. Mine is a CSF. You can google CSF Rx7 radiator. They seem to run between $200 to $250. I think the Godspeed and Mazdaspeed are both oversized aluminum.

 

Was browsing through threads I had posted in and decided to ressurect this one. Since I posted in this thread I have gotten a Godspeed radiator. My brass/copper one leaked when I got my car back together. Core must've got hit at some point while it was out. It cools much better than my old one or the stock one ever did. The temps stay more stable and haven't gotten as high this summer. This is measured with an autometer gauge. This may not be an apples to apples comparison though since the Godspeed is a dual pass like the Koyo N-flow with an almost twice as thick core as the stock one.