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"Dry" exhaust and Cam Selection Question

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Old 10-19-2012, 09:45 AM
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Default "Dry" exhaust and Cam Selection Question

I'm looking to build some big power small blocks and the cam always seams to be a limitation due to reversion issues and the related limitations on duration.

If I upgrade my exhaust to a 'dry' system with double water jacketed tailpipes, I assume the reversion issue is eliminated completely? Exhaust is a BIG investment.

I can get some headers with big tubes to let big heads breath using a big cam in this scenario?! I am shooting for 600hp so these little 427 cid small blocks are gonna need to breath.

The cam the builder usually uses to produce 610hp in this engine is as follows:
VALVE LIFT WITH 1.5 ROCKERS : INT .580 / EXT .600
DURATION IN DEGREES : ADVERTISED - INT .300 / EXT .506
DURATION @0.050" : INT .253/ EXT .258
LOBE SEPARATION ANGLE : 110º

Thanks for any advice.

Tom
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Old 10-19-2012, 09:52 AM
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with dry exhaust you can use any cam you want,reversion does not happen with dry exhaust.
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Old 10-19-2012, 11:42 AM
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Default Thanks - Dry = Good

Maybe a dumb question, but why doesn't everyone run jacketed, dry exhaust?

Disadvantages?
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Old 10-19-2012, 12:55 PM
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Originally Posted by ttrm007
Maybe a dumb question, but why doesn't everyone run jacketed, dry exhaust?

Disadvantages?

NOISE...
Without great mufflers I could blow your eardrums out in about 10 seconds.
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Old 10-19-2012, 03:05 PM
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Default Perfect!

Originally Posted by zt260
NOISE...
Without great mufflers I could blow your eardrums out in about 10 seconds.
Well, that settles it then. Dry it is!
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Old 10-19-2012, 03:32 PM
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Good Choice!

LOL
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Old 10-19-2012, 05:21 PM
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That is funny.
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Old 10-19-2012, 05:29 PM
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Originally Posted by ttrm007
I'm looking to build some big power small blocks and the cam always seams to be a limitation due to reversion issues and the related limitations on duration.

If I upgrade my exhaust to a 'dry' system with double water jacketed tailpipes, I assume the reversion issue is eliminated completely? Exhaust is a BIG investment.

I can get some headers with big tubes to let big heads breath using a big cam in this scenario?! I am shooting for 600hp so these little 427 cid small blocks are gonna need to breath.

The cam the builder usually uses to produce 610hp in this engine is as follows:
VALVE LIFT WITH 1.5 ROCKERS : INT .580 / EXT .600
DURATION IN DEGREES : ADVERTISED - INT .300 / EXT .506
DURATION @0.050" : INT .253/ EXT .258
LOBE SEPARATION ANGLE : 110º

Thanks for any advice.

Tom
I do love those cam specs though, she is gonna be one ANGRY sounding lady if you go with it.

Are you going with an LS7 or what are you doing?

Last edited by Captain YARRR; 10-19-2012 at 05:53 PM.
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Old 10-19-2012, 08:52 PM
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Default Small block strokers

Originally Posted by Captain YARRR
I do love those cam specs though, she is gonna be one ANGRY sounding lady if you go with it.

Are you going with an LS7 or what are you doing?
427 cube dart shp blocks, pro 1 alum heads, etc... Pretty economical way to put some solid HP numbers in this boat. Should be pushing 1200! I've had small block Chevy hot rods all my life so am doing what the boat is set up for and what I know best (just adding cubes).
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Old 10-20-2012, 04:51 PM
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Originally Posted by ttrm007
427 cube dart shp blocks, pro 1 alum heads, etc... Pretty economical way to put some solid HP numbers in this boat. Should be pushing 1200! I've had small block Chevy hot rods all my life so am doing what the boat is set up for and what I know best (just adding cubes).
Sounds like a killer setup! I'm assuming the 230cc Pro 1 heads? Any idea's on carb? HP950's?

If it were mine I would go Lightning Marine Dry Jacketed headers or Stainless Marine Dry Tails if your going manifolds.
Both should not have a problem with any size cam and should let them breathe when you need it.

Loud is Good!!!!
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