Sydwayz, the 420's and 440 Cyclone's were all black, 425's were rare, but I believe had some blue, 450's had blue valve covers, intake, power steering pump, alternator, pulleys (some blue some black), and carb (just like HP500). The 465 had blue valve covers, carb, black intake. Yes, the 465 was a awesome sounding motor. I remember in 1993 driving a new 22' Velocity with one, man what a rocket. The old school 575 was a pretty mean motor too with the solid lifters and Stellings. Ah the memories!!!!

is the NA575 the highest horsepower pump gas NA motor mercury had built? I know they build the supercat motors but they are pure race motors....

Sorry about the 700sc. Got things confused. I have edited the post.

Yep. I remembered the prop hp of the 800sc, and got it into my head that there was a 700sc from merc. My bad. Sorry guys.

Yes, as posted earlier. A 540 cid. motor. When I get back from our vacation, I'll find the specs if you are interested.

HP 575 Data sheet