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ak907jon
Joined: 07 Feb 2010 Posts: 11 Location: Lake havasu, AZ
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Posted: Thu Apr 15, 2010 12:38 am Post subject: Trying to build 600hp SB |
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I am rebuilding my sb zz383 (425 hp) and I am putting pro-comp 4340 5.7 rods in it, with new pistons and not sure if i should put flat or dome, what would be better for a 15ft sprint boat? still trying to keep the comp to no higher then 11.0 to 1 . I have the aluminum fast burn heads, I want to put maybe bigger valves? and better seals and guides of course. Trying to reach
600hp marker with a good base motor. Want it to be reliable and hold high rpm. Any suggestions? Thank you _________________ 15ft zz383, steel bottom |
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boosted
Joined: 04 Jun 2009 Posts: 378
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Posted: Thu Apr 15, 2010 8:21 am Post subject: |
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If you want to hit 600 hp with that size of engine you will need better heads. With 11:1 you are going to have to rev it some(over 6000 rpm). so a set of AFR195's or something like that. The fast burn heads are ok but a little small to rev it for that kind of power. Yiour cam will have to be close or over .600 lift at the valve also like maybe a comp 294xr solid kind of thing. Victor junior intake and at least an 850 carb. _________________ Mark
Lets go back I think we missed one rock! |
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ak907jon
Joined: 07 Feb 2010 Posts: 11 Location: Lake havasu, AZ
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Posted: Thu Apr 15, 2010 11:28 am Post subject: zz383 trying for 600hp |
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Thank you mark. Also to get 6000rpm would It be good to use a B impeller
with an Inducer? What kinda speed? Thanks _________________ 15ft zz383, steel bottom |
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boosted
Joined: 04 Jun 2009 Posts: 378
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Posted: Thu Apr 15, 2010 1:45 pm Post subject: |
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You would have to run a b/c Agressor for 600 actual hp to turn 6000 so corrected would be close to 630. Otherwise you would run a c Agressor or a B AT, Berkely.
As far as speed goes it would really depend on the boat. If it is a delta pad then you going to hit a wall around 75 mph or less. Not to say it won't go faster but it is going get a little weird to drive. A straight V hull may go a little faster but will want to fall on it's side some. Steptech will go faster but with such a short boat 85 might be the wall point. That my .02 and I am far from being an expert but I have tried a couple of times to go fast in a boat that isn't designed for it and it gets interesting. Can you say hop skip and a bow hook. _________________ Mark
Lets go back I think we missed one rock! |
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ak907jon
Joined: 07 Feb 2010 Posts: 11 Location: Lake havasu, AZ
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Posted: Thu Apr 15, 2010 2:54 pm Post subject: zz383 trying for 600hp |
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Thank you for the info Mark. _________________ 15ft zz383, steel bottom |
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riverboater
Joined: 10 Dec 2009 Posts: 153 Location: Prince George
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Posted: Thu Apr 15, 2010 10:11 pm Post subject: |
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I have played with several big cu.in. small blocks, looked hard for the big HP numbers. copied several of those 600 hp engines you read about in the mags. funny thing is when they went onto the dyno they didn't produce the sort of HP talked about. The fellow that ran the dyno was more than impressed with the output as he had seen lots of different combo's and rairly saw much over 450 real hp. The big numbers came from the blower engines.
riverboater |
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ak907jon
Joined: 07 Feb 2010 Posts: 11 Location: Lake havasu, AZ
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Posted: Thu Apr 15, 2010 10:22 pm Post subject: zz383 trying for 600hp |
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Yep I here ya, It would be nice to put a whipple charger on it! _________________ 15ft zz383, steel bottom |
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RPM
Joined: 17 Dec 2006 Posts: 189 Location: Nechako
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Posted: Thu Apr 15, 2010 11:56 pm Post subject: |
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forget about the hp number unless you are paying for a professional build by a shop with a dyno . it's still only what it will turn for an impeller in your boat that matters and 600 from a 5.7 rod 383 going by impeller charts seems a little optimistic . your fast burn heads with a good valve job and 202-160 valves if needed should be close to what you'll get with a set of 195 afr's , but are a lighter casting and not suitable for sustained wot. with a set of lightweight flat tops you easily get over 11:1 . i'd pick a hyd. over mech. profile for better durability with the lighter head castings and with a 5.7 rod look at getting the torque to peak by 4800, with a B impeller you should see 5600+ depending on alt. with a comp xr294hr , and a good 750 dp on a 2926 super victor. good luck with your build . _________________ Rick's Precision Machine
Prince George B.C.
Machining - Welding - Repairs |
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Will R
Joined: 31 Jul 2005 Posts: 677 Location: NWT/Alberta
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Posted: Fri Apr 16, 2010 7:27 am Post subject: |
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I'd say sell your zz383 instead of trying to modify it as it reduces reliability if you dont build it right and expensive! take the money from that and combine it with what you where going to spend on it and buy a crate motor like the ct525 you will probably come out ahead anyways and have the peice of mind of running a well built motor! A few racers have run this motor in race application with great results! _________________ When in doubt hammer down! |
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ak907jon
Joined: 07 Feb 2010 Posts: 11 Location: Lake havasu, AZ
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Posted: Sun Apr 18, 2010 9:52 pm Post subject: zz383 trying for 600hp |
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Hey, thank you guys for the info. Now the choices begin!! _________________ 15ft zz383, steel bottom |
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