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[LS1] Exhaust

M01ST

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Got a 410 hp ute with single 3.5" exhaust, was wondering what would be better twin 2.5" or twin 3"?
 

cpbait

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that the sureflow exhaust?
 

Munz

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3in will be a deeper note
 

M01ST

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Yer but I'm thinking the twin 3" will have a lot let back pressure causing less power but however will heaps better?
 

Jesterarts

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Is it 6l or 5.7l? N/A or FI? Is it running gears? Auto or manual? Plans for more mods?
 
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rb26dett

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Twin 2.5 would be good for that power.
 

M01ST

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It's a cammed vu ss ute standard diff gears manual h/d clutch 25% underdrive pulley
 

cpbait

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I'm looking at putting that sureflow twin 2.5 into single 3.5" on my vy ss with cam, 383 stroker motor, been told it will be fine, i do have 1-7/8 headers and 3" cats, whether that makes a difference or not i'm not sure.
 

Jesterarts

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I'm looking at putting that sureflow twin 2.5 into single 3.5" on my vy ss with cam, 383 stroker motor, been told it will be fine, i do have 1-7/8 headers and 3" cats, whether that makes a difference or not i'm not sure.

Why have 3" cats feeding a twin" 2.5 to single 3.5 system? Wouldn't 2.5" cats be better so you have a smoother flow and more constant velocity?

RE: OP.

I would say a twin 2.5" will do what you need. You will lose a touch of bottom end torque going a twin 3" and if you're running stock gears I don't know that's something you would want.

The 3.5" you already have is doing the job you need, so I'm assuming you're chasing sound?

If so, then I can't say as sound is subjective. If you are after just something different in a twin, then 2.5" will do the job providing you get a decent brand and if you're planning on going 330rwkw+ in the future then I would be looking at a twin 3"
 
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