502 carb 550hp - Blower vs NA
#11
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#13
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And NO Mild I'm not going to be selling my pair. They will eventually go on the Panther.
Last edited by Rookie; 07-17-2015 at 08:28 PM.
#14
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Here's my argument in the blower size. Small blowers highly overdriven, make excellent torque down low. Lets say the 250 vs the 420 blower at full throttle, at 3500RPM, both making 6lbs of boost. The 250 will more than likely make more torque there. You probably wont start seeing gains in power, until about 5000RPM. Then, the big blower will walk away from the small blower. Especially when you run hard for long periods of time like, in a boat.
So, if drives staying together was a concern, thats a tough call.
To get back to the original question, its easy. The 600sc merc engine, was nothing more than basically a 502 mag, with a different cam, which was a flat tappet, dished pistons for 7.5:1, and the 420 blower, with twin 700 carbs. It was a very reliable engine, and many added chillers, and cranked up the boost. I know of one guy, who installed chillers, cranked the boost to 10psi, and ran that setup for 10 years!!
I'm a fan of blowers, but like mike tkach says, for only 550hp, no reason to add them. I'd rebuild the setup with some better components to get to 550HP, with 9:1 or a hair less compression. Run that for a while. Then, if you wanna get silly, toss a blower on there, like the 420, or 871, and enjoy 700-750hp as well.
So, if drives staying together was a concern, thats a tough call.
To get back to the original question, its easy. The 600sc merc engine, was nothing more than basically a 502 mag, with a different cam, which was a flat tappet, dished pistons for 7.5:1, and the 420 blower, with twin 700 carbs. It was a very reliable engine, and many added chillers, and cranked up the boost. I know of one guy, who installed chillers, cranked the boost to 10psi, and ran that setup for 10 years!!
I'm a fan of blowers, but like mike tkach says, for only 550hp, no reason to add them. I'd rebuild the setup with some better components to get to 550HP, with 9:1 or a hair less compression. Run that for a while. Then, if you wanna get silly, toss a blower on there, like the 420, or 871, and enjoy 700-750hp as well.
#15
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I know there have been plenty of "NA vs Blower" threads and I have searched them. But, I would like to hear opinions from the gearheads on here about this specifically.
If you had a 502 Mag (carb version) and you wanted 550hp, would you replace the cam, lifters, pushrods, rockers, springs, intake, carb and exhaust or look at putting a small blower (420 or similar) blower on top with upgraded head bolts/studs, head gaskets and valves?
Which is more cost effective and reliable at this moderate hp level?
If you had a 502 Mag (carb version) and you wanted 550hp, would you replace the cam, lifters, pushrods, rockers, springs, intake, carb and exhaust or look at putting a small blower (420 or similar) blower on top with upgraded head bolts/studs, head gaskets and valves?
Which is more cost effective and reliable at this moderate hp level?
UD
#16
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I know there have been plenty of "NA vs Blower" threads and I have searched them. But, I would like to hear opinions from the gearheads on here about this specifically.
If you had a 502 Mag (carb version) and you wanted 550hp, would you replace the cam, lifters, pushrods, rockers, springs, intake, carb and exhaust or look at putting a small blower (420 or similar) blower on top with upgraded head bolts/studs, head gaskets and valves?
Which is more cost effective and reliable at this moderate hp level?
If you had a 502 Mag (carb version) and you wanted 550hp, would you replace the cam, lifters, pushrods, rockers, springs, intake, carb and exhaust or look at putting a small blower (420 or similar) blower on top with upgraded head bolts/studs, head gaskets and valves?
Which is more cost effective and reliable at this moderate hp level?
Plus adding a blower....properly....is more work then one might think.
I personally would select parts that are the best value. Sometimes we all go overboard and there are plenty of good choices that will produce very similar results for less money. For example, a 550hp build with some good flowing, less expensive, iron heads over aluminum.
Keep us updated! Enjoy!
#17
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This was a hypothetical question. Looking at a boat with a low hour(about 50) 502 Mag carb. I know you can get 550hp with cam, lifter, springs, etc. I understand that is the route most taken.
But, with all the used blowers out there it got me thinking that may be a better option. Bigger blower spinning slower = less heat and more reliability than a smaller blower and less valve train wear.
Wheels were spinning so I was looking for opinions.
But, with all the used blowers out there it got me thinking that may be a better option. Bigger blower spinning slower = less heat and more reliability than a smaller blower and less valve train wear.
Wheels were spinning so I was looking for opinions.