Just some common sense thrown in here... We debate alum vs copper/brass ad-nausea. The bottom line is they both work and can work with higher horse power applications. Talk to your local radiator shop and they will tell you alum can't be fixed if damaged, and can't be rodded out like a brass/copper unit can. Brass/copper also isn't prone to electrolysis like alum is. The modern oem alum radiators I see on new cars are alum cores with plastic tanks that are crimped and glued together. Should the hotrod world follow the oem lead here as well? They work well in new cars don't they!
My whole point is and I tried to make it in the last thread asking "what's the best?" it's all about what you want and what you are trying to achieve. You can re-core a stock set of tanks with staggered tubes or buy a stock style replacement if you want to retain some of that vintage look even if you are leaning towards pro-touring. You can run a big polished alum radiator and vintage finned or MT valve covers too if that is what you want. The best is relative at best, Someone driving a 550 Maranello might laugh at a chevy with respect to "best" just as some chevy guys are arguing over best radiator. Both a Chevy and a Ferrari will get you down the street. Do you need the Ferrari though? Same with Alum vs Brass/copper radiators... Alum is one answer to cooling your classic, it's not the answer though. Same with electric fans... I'm not against Alum radiators or electric fans, I just know the other stuff works and works well if it's setup properly and maintained well.
Dennis.. while I know you try to appease everyone here with their points of view and experiences and I respect that and I agree with most, but on this subject I couldn't disagree with you more with all due respect as to "what is best?". Maybe I/we are saying the same thing just in different perview/context... I don't know?
Unfortunately, some more ad nauseam..... when someone asks what's BEST
or in this case "does aluminum work"?... it's black and white for the most part to me (yes.. I am an engineer and things appear to me this way to a probably fault) . Yes.. I do agree tht money has something to do with it and I really respect those who are on a tight budget for sure (been there... and well.... still there).... but when you want the BEST
.. .there is A BEST
! And moreover it's all to do with design and media frankly. While application(s) dictate fitment.. the rest is pure physics.
Don't get me wrong...there is NOTHING WRONG with brass/copper/radiators per se, if they are adequate for your applications then GREAT don't go change for the sake of change! But, the more hp you add and the want and need for more conditions in which to be able to function (such as here in Atlanta traffic) with air conditioning wanted as well... the old OEM stock radiators (and other parts for that matter)are NOT the "best", period. I hate to burst everyones bubble on this! Even in their day it was nip and tuck... I had a 65 SS Impala with air that was marginal at best in Indy climates and NO traffic to speak of. I had a number of friends that had everything from BB Corvettes to 440 GTXs and all had marginal cooling systems in high temperature environments. One of my friends fathers had the largest Chevrolet dealer in the midwest and they were commonly plagued with "performance car cooling issues" to quote his father directly. This was due to OEM designs and specifications in their day.
And, let's face it.. we are making more hp with those very same engines with improved VE numbers .. even some of the pure stock applications will make better than "factory" claimed horsepower numbers easily with the availability of low restriction exhaust/headers, induction systems and just boring out those engines for rebuilding changes everything. And.. add airconditioning.. well that's another hit needing more efficiency. Also, in traffic ladened communities (and traffic has increased expotentially as we all know in every place) the tarmac/road ambient temperatures has increased dramatically too. When sitting at a light in Atlanta 30 years ago the ambient pavement temperature might have been 5 to 7 degrees higher than the ambient. Today.. it's typically 12 to 20 degrees!! Hence, you have to have a more efficient cooling system to get you the same performance as you did in yesteryear at the same intersection usually. I get literally dozens of emails or phone calls a month from either car builders and/or owners asking why their 502 is not cooling when they put it in their "stock" application cooling system. I have seen this hundreds of times!
Today's applications are much more sophisticated for sure...OEMs today design for much higher demands than 30 years ago do to these wanted conditions. Now, OEMs are designing for maximum tarmac/road surface input temps (air that actually gets sucked into the radiator for cooling) in excess of 125 degrees, whereas in 1967 is was only 100 degrees. This is NOT my opinion, but actual GM specs now.... as well as other OEs. While you can poke fun at OE radiators with plastic tanks.. actually some of these will cool better and last longer than conventional all metal radiators. Yeah.. yeah.. I know... they are supposedly cheaper but composites used for these are sometimes tougher than our traditional thinking "metal" in radiators for sure and will take more flexing and abuse and are actually engineered for that specific application. But I agree with most here... I myself would not pick one of these for my applications either... I want ALL aluminum!
"Why aluminum?" is the question and just what makes it "the best" choice? Again.. no big deal if you have a copper/brass one..... and their are plenty of quality vendors out there for sure.... so if it works.. don't change it! While aluminum is lighter and yes.. somewhat less in the thermal conduction department (when compared to copper), it is also stronger and this is the very key to it's success for cooling efficiency. This "stronger" element of aluminum allows the functional tubes to be designed in ways that are far more efficient than just the "conduction" transfer losses compared with copper/brass. Aluminum tubes can be made not only larger, but manipulated for custom size, footprint and internal coolant control that you can't get with copper. And.. on the external design front, large aluminum tubes will have appreciably more finnal "footprint" than smaller copper tubes and will not need four or five rows of tubes (which each row gets less efficient as you progress back thru the radiator core). This is another huge design upgrade(s) with increase in heat reject ability. Another major issue that affects the overall cooling ability of either radiator is flow. Larger tubes present far less "flow resistance" both on the pressure and suction sides. Because our water pumps are centrifugal designed and not "positive displacement" designs, resistance to flow is a real upgrade if you can reduce this. The result is that you will see a flow increase thru the aluminum designs.
Simply put, area for area with the same waterpump source provided, the large-tubed aluminum radiators will provide in the area of 25% to 40% more heat rejection due to all these aforementioned features when compared to a copper/brass/solder model. This is why all the OEMs are using aluminum now. Smaller footprints, higher flow, high efficiency designs all contribute to a "best" product.
So, what is best for improving "overall" cooling in general? Notwithstanding the radiator upgrade, there are simple and inexpensive upgrades to the stock system (or any system for that matter) that can help. First, flow is king and any quality aftermarket high/volume water pump will increase flow dramatically throughout the RPM range. Old OEM stock waterpumps flow about 5 to 7 gpm at best at idle and only 35 to 40 gpm at cruising rpms. Typical high volume aftermarket waterpumps will produce from 12 to 18 gpm at idle and 50 to 65 gpm at cruising rpms (some even as high as 80gpm!). As you can see a huge improvement. Any airflow improvement will also be an efficiency improvement. While stock fans are okay for stock applications, it's oft found out that they are NOT adequate for higher hp or demand applications. Upgrading your fan to a larger/more blades etc one may work, but high output electric ones will out perform any stock mechanical fan period. A classic example is the Mark VIII fan with around 4000 cfms of production. There is NO OE fan that will come close, albeit you will have to make electrical upgrades for the Mark VIII as well.
And.. finally just to clarify some other points please..... "aluminum radiators are susceptible to electrolysis". While this used to be an issue with only a handfull (and small surface areas) of aluminum parts present in the system, with an aluminum radiator (and high surface area availability) and quality corrosion (or antifreeze) inhibitors this is not a problem at all. Mixed and matched metals in modern OEM applications survive without problems as long as you maintain the cooling system. This is also easily checked on as well. Another point... aluminum radiators can't be "rodded" out etc. Well, actually if you maintain your cooling system with modern long-lived antifreezes and corrosion inhibitors and use distilled water, you will have NO NEED for rodding out period. Also to your point... you can't repair aluminum (sometimes is true), but aluminum is much stronger (especially the welds and tube thickness/strength) and the incidence of repair (this according to seven OEM acuarial information on failures) or failure is only 17% of copper/brass models of yesteryears. So, the reliability factor with fully aluminum radiators is huge simply due to their inherent strength! This is another motive for the OEs to to toward aluminum.
Now..... for everyone out there that does not know me.. I will restate for the record that I do NOT have anything to do with any of the vendors here...or anywhere else for that matter. I think I am a pretty "balanced and fair" reporter really.. with just the science to back me up. So to me.. it's black and white. Any design which offers any of these improvements and features will be the "best".
Pardon the Interuption!