573 vrs 553 Edelbrock?


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By Richard - 13 Years Ago
What is the difference between these two manifolds. Can you port a 553 to match a 573 .

Thanks,

Richard
By The Master Cylinder - 13 Years Ago
Might be kind of hard to reach into the passage ways to port. Maybe just port match to your heads and blend some corners. Or you could have it Extrude Honed...



Thing is will the carbs flow enough to take advantage of the porting. w00t Three Stromberg 48's flow ~500 cfm, 97's slightly less.
By MarkMontereyBay - 13 Years Ago
If I remember correctly, Ted Eaton's extensive manifold dyno testing had the 573 as best with the 553 right behind it. JMOP, but unless racing and trying wring out every bit of power, probably not a difference between them to shout about. If maximum performance is the goal, 3X2 setups would most likely be given up for a more efficient single 4BBL. I have the 573 on my Tbird but also have a 553 that someone gasket matched to the larger port size.
By The Master Cylinder - 13 Years Ago
Yes the 553 came in third behind an Edmund's. I have a 553 that was port matched to my "G" heads running Strombergs.
By Richard - 13 Years Ago
Sounds like port matching is the way to go. Thanks Guys
By Ted - 13 Years Ago

Here’s the link to the test results for the 3X2 dyno test.

http://www.y-blocksforever.com/forums/Topic40554-3-1.aspx 

The 553 and 573 intake dyno results are very close to each other with the 573 intake being the better of the two.  While it’s probable that porting the 553 intake will bring up its horsepower numbers up so that they equal those of the 573 intake, testing this scenario is actually the only way to know for sure.  I’ve now done enough intake porting that you have to be cautious in removing material in the manifolds simply due to the results sometimes going backwards instead of actually improving.  Instead of actually match porting the intake to the heads, results are better in some instances where only the ‘inside’ edge of the intake port is port matched to the head while the ‘outside’ edge of the port is left intentionally alone with a step remaining between the intake and the head.  A full port match can cost some lowend torque without any improvement to the top end horsepower numbers.
By 46yblock - 13 Years Ago
Ted (6/2/2012)

Here’s the link to the test results for the 3X2 dyno test.

http://www.y-blocksforever.com/forums/Topic40554-3-1.aspx 

The 553 and 573 intake dyno results are very close to each other with the 573 intake being the better of the two.  While it’s probable that porting the 553 intake will bring up its horsepower numbers up so that they equal those of the 573 intake, testing this scenario is actually the only way to know for sure.  I’ve now done enough intake porting that you have to be cautious in removing material in the manifolds simply due to the results sometimes going backwards instead of actually improving.  Instead of actually match porting the intake to the heads, results are better in some instances where only the ‘inside’ edge of the intake port is port matched to the head while the ‘outside’ edge of the port is left intentionally alone with a step remaining between the intake and the head.  A full port match can cost some lowend torque without any improvement to the top end horsepower numbers.

Interesting.  It seems counter to reason that the inside edge may give better results than the outside edge.  I would have thought the reverse.