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What intake Manifold Worked 304 v8?

Deuce

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So cams have no influence on power band? Who knew?

Intake runner length, along with size and taper are one of the many things that influence the overall power curve.
And all the tuning effect exhaust has too.
That is a BIG piece of the picture.
 

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Yes cams do but when you compare intakes on a engine with the same cam and heads but only the intake changes you can see the effect.
Single planes perfom better above 6000-6500rpm so when you install one it is recomended that you use a cam from 4000-8000rpm range to utilize the gains of the manifold and visa versa.
Dual planes have more power everywhere on the dyno graph up untill 6000-6500rpm so like in the OP's case if you have a cam that drops off at 6200rpm you're just throwing horse power away using a single plane.
Can I be more clear about this?
I think you will find your average single plane has a larger cross section area compared to your average dual.
This will effect torque Curve obviously, and you will note my original comment advised for smallest single plane he can find.
 

shane_3800

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I think you will find your average single plane has a larger cross section area compared to your average dual.
This will effect torque Curve obviously, and you will note my original comment advised for smallest single plane he can find.
Effective length is a comparison between cross section and actual length. Just like how we refer to engines being under square or over square.
Bringing cross section into this discussion is useless because I'm talking about effective length.
 

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Yes cams do but when you compare intakes on a engine with the same cam and heads but only the intake changes you can see the effect.
Single planes perfom better above 6000-6500rpm so when you install one it is recomended that you use a cam from 4000-8000rpm range to utilize the gains of the manifold and visa versa.
Dual planes have more power everywhere on the dyno graph up untill 6000-6500rpm so like in the OP's case if you have a cam that drops off at 6200rpm you're just throwing horse power away using a single plane.
Can I be more clear about this?

Sure when you are using big cams. I've seen a dyno graph doing the same test where there isn't a huge difference between the SP and DP intakes.

You can't just categorize all SP manifolds as been the same either.
 

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Yes cams do but when you compare intakes on a engine with the same cam and heads but only the intake changes you can see the effect.
Single planes perfom better above 6000-6500rpm so when you install one it is recomended that you use a cam from 4000-8000rpm range to utilize the gains of the manifold and visa versa.
Dual planes have more power everywhere on the dyno graph up untill 6000-6500rpm so like in the OP's case if you have a cam that drops off at 6200rpm you're just throwing horse power away using a single plane.
Can I be more clear about this?
Engine component selection is much more complex than that. Just because a control camshaft was used for testing doesn’t mean that the results can be applied to all engine combos, taking only the powerband into consideration.

Not all single planes/dual planes are created equal. There are so many variables that must be considered. EVERY single engine responds differently to the same mods (even the same model). Repeatability is difficult to achieve.
 

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I agree that a performance manifold that appears visually similar to stock is an appeal in many instances.

From memory, VN heads with approx 5cc valve recess in pistons gives 10.5comp.
That is why I assumed 11s for OP
But come to think of it, all my memory calcs are for 355", not 304" which would make a difference for sure.
Yeah think with 355, you achieve 9.5:1 with stock vn heads and 12cc dished pistons. Very different haha
 

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No you're all incorrect. The cam will change powerband and intake runner length will affect torque accross the band.
When you're looking at intakes it all comes down to runner length it's not some black complex art. I love how people that don't understand what they're talking about always just say "it's more complex than that" or "it's too complex to explain" I'm guilty of this my self.

I've litterally told you whats happening and gave you my source of information and yet you wont listen.
 

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shane_3800

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See how the manifolds work exactly the same on the LS1 vs the LS3. This is because manifolds don't care weather they're bolted to a holden V8, LS1 or LS3 they behave the same way and it's all got to do with runner length.
 
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