Intake off Gen IV 454 420hp
12-31-2008, 05:10 PM
#11
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12-31-2008, 07:59 PM
#12
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Whats the consenses on the intake used on a 496 (stroked 454) and a demon 750 with dart alm 310 cc alm. heads? Mine seems to stop at 4900 was wondering why ? running a crane hyd. roller specs say 5600 only running 23 mirages. Am I running out of air ? Some say 850s at least?Or is it the intake?
Just because 5600rpms is what the cam is designed to run at for max rpm, doesn't mean it will in your boat. Your heavy boat needs torque and your engines are probably starting to fall off in torque too much at about 4900rpms. Go down 2" in pitch on your props.
I agree, a 750cfm is on the small side for 496ci.
12-31-2008, 09:29 PM
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rpm air gap
when you say cam specs say 5600, but for what cubic inch engine, that cam may do well to 5600 in a std 454, but with your stroker may only work to 5000. what intake are running ? the 750 seems small to me, altough I'm running a 750 on my 509, next season I'm going to swap a 850 and see on gps what its worth...but thats months away...Rob....
12-31-2008, 09:36 PM
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Just because 5600rpms is what the cam is designed to run at for max rpm, doesn't mean it will in your boat. Your heavy boat needs torque and your engines are probably starting to fall off in torque too much at about 4900rpms. Go down 2" in pitch on your props.
I agree, a 750cfm is on the small side for 496ci.
I agree, a 750cfm is on the small side for 496ci.
12-31-2008, 11:24 PM
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My mechanic and also the company that sold me the motor said that I would be able to put my intake off the 420hp on the 330hp. Just wandering what kind of results I'm gonna see. I could get 60-62 in a 88 240 sport with the 420, but its really tired ( mechanic said probably only puttin out 325hp). I'm hopin to see the same if I take my setup off the 420 and put it on the 330, with a few adjustments. Anybody do anything similar to this and what were the results.
01-01-2009, 02:47 PM
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What do you mean its gonna cost me? Do you mean the engine itself is not going to run as well as it would with matched ports? And if I'm correct the ports on the 330 are considered oval, they are just the small oval and there is also large oval ports (maybe this is wrong, I'm still learnin. Thats why I'm posting).
