540-598 with Chevy Rect port heads?
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I see all these deals now for LARGE short blocks(540-572-598)
and am wondering if I could use my old Hi-perf Chevy heads and have a cheap combo or will I need aftermarkt heads to get the best out of this block? OK, I know the aftermarket heads will do better,, but since everyone says the Chevy heads are to big for a boat seems like they'd be a good choice for a BIGGER motor. Whaddaya'll think? $3900 for the bottom,free for the top and 550HP??
and am wondering if I could use my old Hi-perf Chevy heads and have a cheap combo or will I need aftermarkt heads to get the best out of this block? OK, I know the aftermarket heads will do better,, but since everyone says the Chevy heads are to big for a boat seems like they'd be a good choice for a BIGGER motor. Whaddaya'll think? $3900 for the bottom,free for the top and 550HP??
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Sure. Rect port Chevys will work dandy on a 540.
Bulldogs made 500 horses with a pretty mild cam.
If 550 horses is your goal, rectangle ports will get you there quick cheap and easy.
Pocket port. A little bowl work. Gasket match. Deck them for flatness. CC them. You're there.
If you're going to spend the money and effort on a REAL motor (572+ tall block) then I hate to see you choke yourself with stock iron Chevy heads. They aren't junk, but aftermarket heads free up so much more power..
But a 540 with rectangle heads? Nothing wrong with that.
Bulldogs made 500 horses with a pretty mild cam.
If 550 horses is your goal, rectangle ports will get you there quick cheap and easy.
Pocket port. A little bowl work. Gasket match. Deck them for flatness. CC them. You're there.
If you're going to spend the money and effort on a REAL motor (572+ tall block) then I hate to see you choke yourself with stock iron Chevy heads. They aren't junk, but aftermarket heads free up so much more power..
But a 540 with rectangle heads? Nothing wrong with that.
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What do yall think about the deal on ebay for 572 short block unassambled $3299.00 and assembled & balanced for $3999.00 sure makes me think???
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cools, Ives seen a local guy use ported chevy iron castings on a 598 with a solid roller cam and it made 780 HP and 800 ft lbs. on the dyno. In fact it went 98 mph in my hull before I bought it. You might be leaving a 100 hp laying in the big alum heads but what the heck, you will do that someday anyway! Greg
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If I do it I would want it unassembled where I can take it all to the machine shop and build the engine myself!!. I called them and they are pricing it with 9.5/1 compression.
They also have good prices on AFR heads???
They also have good prices on AFR heads???
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If you build tall decks, you'll have issues with making the exhaust fit. Some manifolds have so little clearence between them that you'll end up changing to a whole new exhaust. On a single, the pipes still won't line up at the transom.