18 Degree Intake vs 23 Degree

Old 10-07-2010, 09:02 AM
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jreiley
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Default 18 Degree Intake vs 23 Degree

I'm rebuilding my sbc race engine from the ground up. I will be replacing the heads, intake, valve train, etc. Would going to a 18degree top end make sense? I'm shooting for 700hp.
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Old 10-07-2010, 10:34 AM
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TS1955
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With the right components you can get 700hp from a 23 deg motor.

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Old 10-07-2010, 10:38 AM
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curtisreed
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But not as easy as from a 18 motor. We have a 406 that made 705hp with 23 heads and it has had quite a bit of port work on the heads and intake, 15-1 compression on alcohol, with a pretty aggressive cam.

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Old 10-07-2010, 11:09 AM
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jreiley
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If the dollars are basically the same to buy a new top end, I would think the 18degree is the way to go.
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Old 10-07-2010, 11:29 AM
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ccperf721p
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If you are already planning on spending the money, might want to consider a 15 degree setup.
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Old 10-07-2010, 12:29 PM
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jreiley
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Don't the 12,15 and 18 degree heads use the same intake and exhaust.
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Old 10-07-2010, 02:51 PM
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cncmotorsports
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Originally Posted by jreiley
Don't the 12,15 and 18 degree heads use the same intake and exhaust.
12, 15 and 18 degree take the same intake
700 HP is easy with either 23 degree or 18 degree
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Old 10-07-2010, 08:08 PM
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zipper06
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Originally Posted by cncmotorsports
Originally Posted by jreiley
Don't the 12,15 and 18 degree heads use the same intake and exhaust.
12, 15 and 18 degree take the same intake
700 HP is easy with either 23 degree or 18 degree
I respectfully disagree, it's not easy to make 700 HP with 23* heads without spending a ton of money. (why don't you tell us how much you get for a 23* head motor making 700 HP guarenteed/dyno'ed. without additaves/nitrous) Exceptionly/good 23* heads flow maybe 340 CFM. Good 18* heads flow 400 CFM plus, with a 434" it's possible to make 800HP plus with 18* heads for less than $10,000.00 without additaves,
Carb to pan.

JMO

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Old 10-08-2010, 04:18 AM
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curtisreed
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Originally Posted by cncmotorsports
Originally Posted by jreiley
Don't the 12,15 and 18 degree heads use the same intake and exhaust.
12, 15 and 18 degree take the same intake
700 HP is easy with either 23 degree or 18 degree
I'm with Zip on this. 700hp with 23 heads is not "easy". If it were that easy for you guys I would be seeing a lot of CNCmotorsports sbc motors out there, because you guys could sell them cheap, and hearing a lot of buzz about them. Or at the very least you would be selling quite a few of those 23 heads you are using to do it. Not saying it can't be done just saying it ain't easy.

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Old 10-08-2010, 05:44 AM
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jreiley
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Pretty much decided to go the 15/18 route. Not being totally sure what I need to look for other than heads and intake, what else special do I need to look for?
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