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Old 09-11-2004, 10:38 AM   #1
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More Horsepower Please

I want to get more horsepower out of twin 350 Mag's on a 2004 29' Fountain. Any suggestions? Reliability is important, and I am budget conscious!
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Old 09-11-2004, 04:30 PM   #2
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Re: More Horsepower Please

Does anybody reply to these things?
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Old 09-11-2004, 04:58 PM   #3
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2008 all of the above
Re: More Horsepower Please

repower
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Old 09-11-2004, 07:31 PM   #4
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Re: More Horsepower Please

If reliability and budget are important, repowering makes sense.

If your drives are Alphas, your limit is about 325 horses per. It is easy to get 325 out of your motors, but drive reliability will be iffy.

If you're going to go thru the hassle of recutting holes for Bravos, then there's no good reason why some 502's shouldn't go back in instead (aluminum exhausts mans and alum intake will preserve your weight balance, you'll be heavier with te Bravos).

Low boost blowers on your existing motors is your cheapest option (at least the cheapest EFFECTIVE option).
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Old 09-11-2004, 07:46 PM   #5
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Arrow Re: More Horsepower Please

Quote:
Originally Posted by mcollinstn
If reliability and budget are important, repowering makes sense.

If your drives are Alphas, your limit is about 325 horses per. It is easy to get 325 out of your motors, but drive reliability will be iffy.

If you're going to go thru the hassle of recutting holes for Bravos, then there's no good reason why some 502's shouldn't go back in instead (aluminum exhausts mans and alum intake will preserve your weight balance, you'll be heavier with te Bravos).

Low boost blowers on your existing motors is your cheapest option (at least the cheapest EFFECTIVE option).
I would go with blowers and shoot for 375 HP/engine. Just use the tabs and easy take offs and keep the prop a bit on the conservative side so as not to load the drives too heavily at top end; use Redline "heavy" gear lube; keep the "air time" under-control and you will have a nice package that will have good durability.

Use the extra power to enjoy a better cruising speed and an occasional short burst or two. We see guys with 600 HP and even 700 HP running Bravos with good results if they are careful so I think you can do this and have fun for a reasonable price.
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Old 09-12-2004, 12:12 AM   #6
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Re: More Horsepower Please

I have 2 sets of M3 prochargers I'm pimpin? You'd have to convert from BBC mount to SB and go carbed.
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Old 09-12-2004, 08:54 AM   #7
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Re: More Horsepower Please

I would assume that a 2004 has Bravo drives...
A good exhaust system, like Stainless marine, will give you an extra 150-200rpm and remove some weight.
If it is within your budget, superchargers will give you the biggest gains.
Twin big blocks makes a 29' too heavy in the ass, so if you want to re-power, stroker smalls would be better in my opinion...
Good Luck!
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Old 09-12-2004, 10:11 AM   #8
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Re: More Horsepower Please

I I have Bravos on my boat, so I am not too concerned about getting too much horsepower unless I go really extreme. I've heard good and bad about supercharges. I heard as long as you keep your boost under 5, you don't have much to worry about. Also, are they just bolt on things, or do you have to replace a bunch of parts in the engine to preserve reliability?
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Old 09-12-2004, 10:13 AM   #9
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Re: More Horsepower Please

Would boosting rpm be effective since I am already at my maximum horsepower. The merc. book says that 4900-5000 RPM is max horsepower.
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Old 09-12-2004, 10:46 AM   #10
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Re: More Horsepower Please

Okay, you got Bravos. Great. You can throw the hardware at your motors and be fine in the drive department.

I'm not sure which "hard parts" are currently in your motors, so someone will need to advise on what internals will need to be upgraded.

Generally, if you're staying below 5400rpm on a smallblock, your stock rotating assembly will be okay. Boost levels below 4 psi require pretty much nothing except bolting on the blower and changing the fuel curves.

M3's are too big for your smallblocks. M1's would be a great choice. As would a small roots blower. Vortech smallblock kits seem to be everywhere these days as well (talking about reasonably priced used systems).

A mild blower grind cam (specific to whether you use a roots or centrif), aftermarket exhaust manifolds, and a 4 psi blower will make you smile.
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