"safe RPM "

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rah64dart said:
what RPM range would be a "safe" range to look to spin a 543 big block with a stock block?
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5500 is safe.....

what internal parts you got....hydraulic cam..roller cam...stock rods...billet rods....cast pistons...forged pistons?
 
Planning 440 source rotating assy aluminum heads external oiling comp cam naturally aspirated wanting 6000 to 6500 ???
 
I'm not familiar with the 440 Source stuff. I know who they are, but have never had any of their parts. I feel it's unfair to call it cheap junk with not having any experience with it. It could be budget parts that are very reliable.

That said, I would think 5800 to 6000 rpm would be safe assuming the rotating assembly is well balanced.

What is the RPM range for the cam?
 
rah64dart said:
what RPM range would be a "safe" range to look to spin a 543 big block with a stock block?
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Take it for what its worth, but i would save my lunch money for an aftermarket block.
Long stroke and thin 440 main webbing makes me queasy lol...............im in the same predicament lol
 
cj391 said:
Take it for what its worth, but i would save my lunch money for an aftermarket block.
Long stroke and thin 440 main webbing makes me queasy lol...............im in the same predicament lol
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think I`ll limit my 4.250, long rod, stroke to 6250 tops.
 
I couldn't kill the engine in my old car.... stock non filled RB block, stock forged 440 crank welded and stroked to 4.15, stock LY rods, LIGHT Ross pistons and pins, ARP main studs with stock caps, stock oiling. this was the basement for my mild ported Stage VI heads and Ultradyne NF69 mech cam shaft. Had the shift light set at 5600, trapped at 6200, best of 10.18 in Vegas and ran 9.93's on a string in Bakersfield. Had some signs of cap walk everytime we tore it down, but not as bad as most I'd seen. Kept timing below 36 degrees.
 
Something else has to be thought of...After a safe 5500 rpm would it still be making power or harming the engine? I know some friends that think reving the snot out of a motor is cool but one has to use common sense and think does it make anymore power!! Just my opinion..
 
CUDACOX said:
Something else has to be thought of...After a safe 5500 rpm would it still be making power or harming the engine? I know some friends that think reving the snot out of a motor is cool but one has to use common sense and think does it make anymore power!! Just my opinion..
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if it`s balanced down to knats ***, "girdled", main stud, line honed partial filled block w/ alum. main caps, I wouldn`t be afraid to spin it to 6200. --jmo---bob
 
CUDACOX said:
Something else has to be thought of...After a safe 5500 rpm would it still be making power or harming the engine? I know some friends that think reving the snot out of a motor is cool but one has to use common sense and think does it make anymore power!! Just my opinion..
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Your'e absolutely right. Whats the point if its not making any more power after 5400-5700 ??
 
Last 440-452 that i ran with the block partially filled with casting epoxy and "cap straps" that i make main studs with ported max wedge heads dual dominators on zeeker tr 750 roller, made about 775hp. motor would go to 7500 no problem but fell off after 6800-7000 even with all that hardware.never hurt the block but it crack stock steel cranks. that being said i would say 6500 max if everything is done well but i would try to make power lower and try to keep it closer to 6000 and let the torgue work for you.with those heads ported on that big a motor it will flatten by 6500 or less anyway.paul
 
It's not a 543 but I have a 500" out of a stock RB block that is NOT filled. Stock main caps with a girdle. I've been spinning it to 7200 consistently and it's seen 7,600 a few times at the track. It's going on it's 3rd season now at over 750hp.
 
The parts used will not be as big an issue as the stroke. I spun a 4.15 to 7300 through the traps until I lost a ring on stock caps with studs. I did notice a crack above #4 but no cap walk. the bore was bad on my block.
I would not do the 540 unless it was a heavy car. If you cant get it done with a 4.15 or 4.25 crank you need better heads.
 
Thanks for all the input was trying to decide on rpm range and have a better idea of what to look for I was sure that I did not want to go above 6500 thanks again.
 
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