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Old 05-16-2008, 09:36 AM
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Ok guys if your starting fresh and looking for around 800hp, build big cu in or go with blowers ? What is best? What would you build? THanks Dan
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Old 05-16-2008, 11:04 AM
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I have blown 540's that are detuned to around 800. Not an problem with them. Now if I could just get the rest of the boat to cooperate.
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Old 05-16-2008, 11:33 AM
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In my humble and totally unqualified opinion, I'd go with huge cubes over blowers. With big cubes, you get the power, torque, and you can keep compression down to regular gas requirements. Plus, you can build alot big-cube performance for the price of just the blowers. I think reliability is better too without blowers.

Axa, chime in here.
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Old 05-16-2008, 11:46 AM
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600 CI gets you real close to 800 hp for less money than blown. Call Ateco
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Old 05-16-2008, 01:45 PM
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To get 800 hp out of 600+/- ci, you'll need tube headers and alot of cam. That's going to mean higher top end maintenance and less valvetrain life. Might be tough to do it at 9:1 which means you're back in the premium fuel ballpark. Plus, you totally abandon the "cool" factor of having blowers. Big motors look like 454's with the hatch up- if that's important to you. The downside is the blowers may not fit under stock hatches and they'll require you to keep a closer eye on things like fuel system and such.

I thought about 622's for my Cig project and decided on 565's with 8-71's. Admittedly- for me it came down to that "cool" factor I was talking about.
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Old 05-16-2008, 07:32 PM
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I have been chasing the NA route for a lot of years and in order to make power, the cam has to be bigger, which in turn causes headaches with valve train. I am attempting to head down the presurized route. 572" with Procharger EFI. I will let you know in a few years what way works better.. That is if we dont have to switch over to electric motors to keep the EPA happy.
I am leaning the way Chris is.. go the cool factor route. Wimpy hydraulic roller, 8# boost.. can be a reliable motor, cheaper than rebuilding a radical NA motor.
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Old 05-16-2008, 08:20 PM
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Simple 509 or 540 with a good SC will be hands down better than a NA. More torque (if screw) and more hp. Run low compression, 8:1 and it will live far longer than a 9:1 NA motor with a 700 lift cam. If worked on quite a few 600ci engines and 800 hp is really at the upper level of power.

If budget was big issue, then use bow tie block, 509ci, 8:1 compression, hydr. roller 632 lift cam/256 duration, dart Pro 1 heads, 8psi, 91 octane, will make 825hp @ 5800rpm.

Blower motors, if done correctly are not less reliable. Thats an urban myth! Does anyone know how efficient a motor is a t 0psi of boost, when the cylinders are just filled enough to not have to scavenge? How about when it's low compression so each combustion cycle has lower temps?

If you said 700, then I would be going either way, but 800, that needs a SC to make it easily.

Dustin
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Old 05-17-2008, 12:45 AM
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I run Merc SC's in my boat. I turn the key and they fire every time with no drama, and no hassels. They have been very reliable. They also have low compression, and run on pump gas.



Plus, blowers are just cool...



Darrell.
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Old 05-17-2008, 07:22 AM
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I also agree if you are building from scratch, build a mild blower motor with good pistons etc, correct blower cam, matched blower/carb setup and water/alcohol injection and you will have a very good low speed features that that much H/P in a non-blown engine just will be tuff to have. also fuel economy and that's getting important to most of us..is going to be better with a blower setup in the cruise speeds. Rob
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Old 05-17-2008, 09:33 AM
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I ask my girlfriend the same question each night!!! Blow or not to blow???
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