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Old 09-04-2003, 06:33 PM   #1
bigvinnie
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going from stock to vette ramhorns

Does changing to the 2.5" manifolds require a change to the head pipes and mounting flange/collar, or are the manifold studs on the vette rams the same distance apart so that I can use my existing plumbing...???

thanks.
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Old 09-04-2003, 07:16 PM   #2
lukecp
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The vette ramshorns dump straight down....your p/u ramshorns should be angled backwards. Unless you already have 2.5" pipes, you will have to change your headpipes and proably the rest of your exhaust system anyways. 2.5" manifolds really won't give you any more power if they are going into a restrictive 2" dual exhaust system. Proably a good time to get a new free-flowing 2.5" exhaust system to match up with your headers.
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Old 09-04-2003, 07:58 PM   #3
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thanks for the reply... my current rams are the small I.D. 4X4 units that dump straight down, but upgrading the entire exhaust system to take advantage of the increased flow makes sense... I believe my current pipes are 2.25", so I'll look into a new 2.5" system. Was thinking about going to the Dynomax hemi super turbo mufflers anyway...

All it takes is money.
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Last edited by bigvinnie; 09-04-2003 at 08:01 PM.
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Old 09-04-2003, 09:05 PM   #4
nu2-72
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2.5" exhaust over 2.0" = 64% increase in flow. Not too shabby.
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Old 09-06-2003, 11:53 PM   #5
Longhorn Man
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Quote:
64% increase in flow.
In theory...but in theory, comunisim works.

If the restriction is before the larger pipe, (As in the manifold it's self) then the extra girth in pipe won't do anything at all.

And acording to what I have read on the subject, that is the case on this situation.
Again, from what I have read...expect more like 15 to 25% flow increase.
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Old 09-07-2003, 08:54 AM   #6
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Read more.
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Old 09-08-2003, 12:12 AM   #7
Longhorn Man
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Even if what I have read is not 100% acurate, you can't deny that the major restriction ir at the top of the manifold when the gasses are moving faster, and the restrictions are greatest.
I would never expect a 60% increase from anything but the best headers.
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Old 09-08-2003, 09:33 PM   #8
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Sure I can deny that.
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