SteveG75

Another vote for Zerex G-05. I have been using it for probably at least 10 years between my small block and big block. Works great.

lurch59

http://www.google.com/url?sa=t&rct=j...W0uIzrr1VNZ76A
http://www.google.com/url?sa=t&rct=j...POnX-unIvgPmFQ
For those who want more than anecdotal evidence.

lurch59

Headers were ceramic coated, and temp was 250 on the temp gauge. Coolant was boiling and thumping in the heads, puked lots of antifreeze into the overflow, same phenomenon that I saw for years in the California desert from my hot rodding buddies, heat soak, boiling, puking coolant....

The13Bats

http://www.norosion.com/evanstest.htm

Other info,

99% of shark owners love the 50/50 pre mixed as recommended by top end radiator manufactures like Dewitts...

7T1vette

If engine had a thermostat and pump and radiator were sized appropriately and compatible with each other, there should not have been any boiling in the heads. Might there be some kind of mismatch between cooling port holes on heads/block/gaskets that might limit cooling flow? Is there a suitable mix of water & antifreeze to elevate boiling point as much as possible? Could the pressure cap be defective and not allowing pressure to build up to rated pressure before dumping?

If you have a hi-flo water pump on the engine, it could be cavitating and allowing steam to form in the coolant. That would surely mess with the system.

lurch59

http://www.google.com/url?sa=t&rct=j...D2fWrVhlOJdTIg Scroll to the end of the page.

It does not surprise me that Norosion found their product to be superior to Evans. I have not experienced the increased temps, increased fan running, increased octane requirements and loss of power the Norosion study claims.

DeWitts' will not tell my why Evans voids their warranty. However, Evans has it's own warranty covering water pump, thermostat, hoses and radiator for as long as you own the vehicle.

I don't mind being in the top 1% of Corvette owners.....

lurch59

Well, I like the way you think. The engine was completely stock and never disassembled as far as I know, so engineering was stock. You make a good point about radiator cap holding pressure, many folks don't check this and consequently are not keeping their pressure within spec to limit boiling. So, it could have been a defective radiator cap, but growing up in hot Southern California I saw so much coolant puking from my buddies hot rods on hot days I just decided to go with a coolant that doesn't rely on pressure to increase boiling temps. And, I am lazy and got tired of flushing and refilling regimens.