HP increase
03-08-2015, 06:27 PM
#14
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iTrader: (1)
I have a harder time with people running 4.5" strokes in standard height (aftermarket) blocks, but a handful do.
Many people running 555's too, even in 502 blocks. IMHO wouldn't worry about it...especially marine rpms.
Many people running 555's too, even in 502 blocks. IMHO wouldn't worry about it...especially marine rpms.
03-08-2015, 07:06 PM
#16
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iTrader: (4)
If Tinkerer wants I will move to it's own thread.
03-08-2015, 07:58 PM
#18
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iTrader: (2)
6.385/4.250=1.5 (Rod ratio 4.25 crank)
6.385/4.375=1.45 (Rod ratio 4.375)
These numbers are so close it's not gonna affect anything (except the peanut gallery). Where it gets better is you are moving the pin up in the piston .0625 which makes a lighter piston. The less weight you have at the end of the rod the better off you are. The 4.375 is a better motor.
Last edited by Black Baja; 03-09-2015 at 04:47 AM.
03-08-2015, 08:09 PM
#19
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4.375/4.250=1.5% (increase in crank angle)
6.385/4.250=1.5 (Rod ratio 4.25 crank)
6.385/4.375=1.45 (Rod ratio 4.375)
These numbers are so close it's not gonna affect anything (except the peanut gallery). Where it gets better is you are moving the pin up in the piston .075 which makes a lighter piston. The less weight you have at the end of the rod the better off you are. The 4.375 is a better motor.
6.385/4.250=1.5 (Rod ratio 4.25 crank)
6.385/4.375=1.45 (Rod ratio 4.375)
These numbers are so close it's not gonna affect anything (except the peanut gallery). Where it gets better is you are moving the pin up in the piston .075 which makes a lighter piston. The less weight you have at the end of the rod the better off you are. The 4.375 is a better motor.
Also, it might only be an increase in 1.5% as you stated. But, 1.3% might be over the critical angle. (The limit) I have no clue, just stating for discussion not argument
03-08-2015, 08:30 PM
#20
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Thread Starter
I haven't talked to anyone outside of these websites.
I have just been kicking a few thoughts around. I plan on building the 598 but don't really want it yet. I have a lot of other things that I need to do to the Daytona that are going to be pricey. The 598 is going to be over $20,000 in parts alone.
If I can rebuild the spare 502 and go from 650 to 800 HP I would be real happy with that and the other changes to the boat. and it would cost only about $5,000 to do it. I was thinking that if I can just replace the crank, rods, cam, lifters and the other wear parts. I was hoping to reuse the pistons I have now.
I could probably get this all done and put it together before spring. I have good heads ( they may need to have some of the wedges ground out ) and a good intake and carb. I need to upgrade the ignition system. I plan on getting a crank sensor. ( last summer when I was checking my total timing - above 3000 RPM it was all over the place.
I have just been kicking a few thoughts around. I plan on building the 598 but don't really want it yet. I have a lot of other things that I need to do to the Daytona that are going to be pricey. The 598 is going to be over $20,000 in parts alone.
If I can rebuild the spare 502 and go from 650 to 800 HP I would be real happy with that and the other changes to the boat. and it would cost only about $5,000 to do it. I was thinking that if I can just replace the crank, rods, cam, lifters and the other wear parts. I was hoping to reuse the pistons I have now.
I could probably get this all done and put it together before spring. I have good heads ( they may need to have some of the wedges ground out ) and a good intake and carb. I need to upgrade the ignition system. I plan on getting a crank sensor. ( last summer when I was checking my total timing - above 3000 RPM it was all over the place.
