putting 3" to 2" reducers on the end of my true duals for more backpressure?
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Joined: Aug 2001
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From: Ames, IA
putting 3" to 2" reducers on the end of my true duals for more backpressure?
Right now my engine is completely stock but I'm modding for the future, hence the 3" true duals. Next spring I'll be installing heads/large cam so until then can I just clamp on 3" to 2" or whatever size reducers on the end of my mufflers (the dump before the axle) for more backpressure until the heads/cam are installed? Seems like it'd be an easy way for a bit more torque until this huge exhaust actually works to my benefit.
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Joined: Jun 2000
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From: North Canton, OH
My younger brother was running a dual 4" setup on his BBC Nova. He put made some plates that reduced the opening to 3" and the car was noticeably stronger.
Shifting later is a good way to get slower ET's and launching higher is a good way to break something when you could be leaving at a lower rpm getting the same if not better results.
A dual 3" is comparable to a 4-1/4" single pipe system. That is very large, bigger than some 9 second cars floating around.
If I were to go with a dual exhaust setup with my mods, I would be looking at running 2-1/2" pipes.
IMO
Shifting later is a good way to get slower ET's and launching higher is a good way to break something when you could be leaving at a lower rpm getting the same if not better results.
A dual 3" is comparable to a 4-1/4" single pipe system. That is very large, bigger than some 9 second cars floating around.
If I were to go with a dual exhaust setup with my mods, I would be looking at running 2-1/2" pipes.
IMO
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Joined: Jan 2002
Posts: 274
From: Decatur
Adding something to the end of your exhaust like that shouldnt really help that much. The thing is you DO NOT want back pressure. Let me emphasize you DO NOT want back pressure. The problem with to large of pipe is not that you loose back pressure it is that you loose velocity. The exhaust gas is able to cool quicker and has more space to fill so you loose velocity. Just changing the outlet side will just be a restriction and not a real help. I would just live with it or not put it on yet.
Ben
Ben
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From: Ames, IA
I never thought of it that way momar...thanks. I understand now why just reducing the end of the pipes won't do ****. I know 3" dual is overkill but I'm planning 420ish rwhp n/a and dont want to be regretting it later if I decide to go with a supercharger or nitrous or maybe stroker.
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From: looking for a flow bench so Brook and I can race
Originally posted by superal
I never thought of it that way momar...thanks. I understand now why just reducing the end of the pipes won't do ****. I know 3" dual is overkill but I'm planning 420ish rwhp n/a and dont want to be regretting it later if I decide to go with a supercharger or nitrous or maybe stroker.
I never thought of it that way momar...thanks. I understand now why just reducing the end of the pipes won't do ****. I know 3" dual is overkill but I'm planning 420ish rwhp n/a and dont want to be regretting it later if I decide to go with a supercharger or nitrous or maybe stroker.
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Joined: Jan 2002
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From: Decatur
Originally posted by treyZ28
well, oldsstroker told me i need dual 3'' catbacks for 425rwhp just as a point of refrance
well, oldsstroker told me i need dual 3'' catbacks for 425rwhp just as a point of refrance
Ben
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