Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

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Johnec1102
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Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by Johnec1102 »

Like title said 0520 to 383 stroker few questions:

Fyi
Looking to run dry ground 3 people in boat 13'6"x 7'6" alumatek hull .

1. Am I doing the right thing
2. What gear box to get and ratio
3. What prop for max push and speed.

4. How much weight are we talking ... estimated.
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kwanjangnihm
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by kwanjangnihm »

this tread has a lot of great info that slidin gator put together on the subject!

viewtopic.php?f=48&t=73132
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He's more trouble than you think, he'll kill your sugar, leave you in the drink.
SWAMPHUNTER45
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by SWAMPHUNTER45 »

Personally if I was going to build a new boat right now it would be hard not to go with a 383 build. While I’m sure the salvage LS fans will bring their opinion I’m attracted to the older sbc builds.

My gear choice would be a 2.55 and it is tuff to beat the Sensenich JX or JW.
Trapper510
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by Trapper510 »

There is a lot to be said about the simplicity of a SBC with a carb.
1 wire for the ignition, 1 for the starter and 1 for the alternator.
My recent upgrade went a little more advanced than a 383 but by application needed a bit more power.
But the previous set up was 383 and it did decent.
Considered a LS but I like simple.
Just my thoughts
16x8 Panther 421 Steve Schmidt 82"JX 3
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kwanjangnihm
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by kwanjangnihm »

Look at the simple math:
1. Cost of SBC engine, new or rebuilt?
2. Cost of new or used gearbox?
3. Cost of new or used RHR prop?
4. Cost of redoing rigging: new motor stand, radiator, moving rigging forward ~12" for gearbox?
5. Sell the 520 & prop to offset CM parts/setup costs?
Seriously add these costs together and make a good decision. Would it make more sense to sell your boat and find a nice CM setup ready to ride?
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
SWAMPHUNTER45
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by SWAMPHUNTER45 »

I have 4 local folks we run with all have 13-14ft boats with 383 power. Engines all by different builders from United Speed World to BluePrint.

5 years ago I would have never told anyone to look at BluePrint as there were a bunch of guys having issues. But after doing some checking I realized most of the issues were guys running flat tappet cams with big gear ratios at high rpm. It’s even quite possible they used oils that did not contain proper ZZDP levels.

This one fellow has hundreds of trouble free hours on his BPE engine and for the money it’s a value. Just if you ever order or build a 383 my advice is to go full roller.

Best of luck with the decision going forward.
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Slidin Gator
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by Slidin Gator »

SWAMPHUNTER45 wrote:
Thu Oct 07, 2021 6:03 am
Personally if I was going to build a new boat right now it would be hard not to go with a 383 build. While I’m sure the salvage LS fans will bring their opinion I’m attracted to the older sbc builds.
No way Swamp, you thinking of moving your next engine block 30 years forward in time? :stirpot: :stirpot: :stirpot:
kwanjangnihm wrote:
Fri Oct 08, 2021 6:38 am
Look at the simple math:

4. Cost of redoing rigging: new motor stand, radiator, moving rigging forward ~12" for gearbox?

Seriously add these costs together and make a good decision. Would it make more sense to sell your boat and find a nice CM setup ready to ride?
X2 on this point, it's just what I was thinking. Switching from an aviation engine to car motor is pretty much a gut the whole thing and start over project, new engine stand for sure and rigging mods or replacement etc. If the hull is not replaceable to you, then go for it. Otherwise I would buy used or build a new whatever you want.

In the case of my LS project, I have an old hull that is close to irreplaceable and nothing else to start with, so I am building rigging and engine stand, prop gear etc. new either way.

In your case, if you have the money to spare, I'd find a boat similar to your goals or just go all in on a new build, all while running that 520. If cash is tight, sell the 520 boat and buy what you are looking for. Most builders are backed up right now, so a good used hull is certainly valuable, used rigging has minimal value unless attached to a good used hull. :banghead:
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.
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Re: Thinking of switching my 0520 for a built 500 hp 383 stroker motor with gear box

Post by SWAMPHUNTER45 »

It would be hard to part with my Cadillac Bray boat but the need for a 16 ft is not there anymore. I could easily fit the wife and Bubba into a 12 or 13ft.

May do a small boat in the spring and sell the big girl.

Will see
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