Merc 502 415hp FWC Question
 

Has anyone upgraded a fresh water cool 415 and kept the cooler?

I am wondering home much hp the stock cooler can support.
Looking at 525/600/700 from Mercury Racing it appears they use the same cooler.
The cooler from the 415 looks close to the same dimensions with the old style thermostat housing.

Any input would be appreciated.
Thanks

Not sure on that package, but as soon as a buddy Whippled his 496ho (est 600hp) he needed a bigger cooler. I for got though, we boat on the lower Colorado and it's 88 degrees (water temp) in the summer.


Darrell.

Yes, I did.. I had a stock 454 Magnum MPI engine that had a Merc Closed Cooling set-up on it. I built a 540 that makes about about 700 hp. I should add that I have AFR heads, not steel. I am sure that they get rid of their share of heat. I was concerned about the Merc heat exchange being able to handle that much more power. I have run this engine for well over 200 hours with the stock heat exchnager without any heat related problems at all. In fact, I used the entire belt serp belt set-up and accessories. So, I say you will be fine.

Thanks!