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350 meg not performing up to par ?

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350 meg not performing up to par ?

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Old 04-29-2018, 11:19 PM
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Default 350 meg not performing up to par ?

I have a 21 foot advantage 21 SRBR Just read did the top end on my small block 355
AFR heads 180cc
edelbrock rpm air gap
scorpion roller rockers 1.5
x4270hr cam
brand new Edelbrock 1409 600 CFM carburetor
msd ready to run distributor Mechanical Advance set to 32į
bravo one drive
Bravo one prop 22p

Max out at 53mph @ 4300rpm will not go higher than 4300rpm
it just doesnít seem right and I canít figure out whatís wrong runs perfect
any suggestions on what I could be
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Old 04-30-2018, 05:13 AM
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Ayuh,.... Ya need a smaller pitch prop to get the rpms up,....
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Old 04-30-2018, 10:12 AM
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What was speed and rpm before?
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Old 04-30-2018, 11:05 AM
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Originally Posted by 30ftpanther View Post
What was speed and rpm before?
stock 350 with blown head gasket 14 x19p four blade offshore prop 50mph @ 5000rpm

Last edited by hotshot537; 04-30-2018 at 09:48 PM.
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Old 04-30-2018, 11:19 AM
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battery switch mounted to floor - I would move that to help keep exposed terminals from forming corrosion. And if its mounted on top of carpet - carpet stays wet plus dry carpet - a fire hazard waiting to happen. Just wanted to let you know. Not picking on you but safety is important as well.
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Old 04-30-2018, 11:47 AM
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Originally Posted by BUP View Post
battery switch mounted to floor - I would move that to help keep exposed terminals from forming corrosion. And if its mounted on top of carpet - carpet stays wet plus dry carpet - a fire hazard waiting to happen. Just wanted to let you know. Not picking on you but safety is important as well.
Itís not mounted at all It screwsto the side of the engine cover when the engine covers installed and is approximately about 1 foot above the floor
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Old 04-30-2018, 05:16 PM
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Have you tried the 14x19p prop AFTER the top end work?
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Old 04-30-2018, 06:39 PM
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You added a blade and went up about 2.5 in the pitch. You need to try a smaller prop.
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Old 04-30-2018, 06:57 PM
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Try a 21p Mirage Plus prop. with that setup.
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Old 04-30-2018, 07:45 PM
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Originally Posted by 30ftpanther View Post
Have you tried the 14x19p prop AFTER the top end work?
yep, this will give you an idea of how much power you have gained. With that setup you want to spin at minimum 5000 rpms.
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