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Discussion Starter · #1 ·
I am thinking that I want the Ram Air/HO exhaust manifolds to put on my 67 with 670 heads. The heads have been port matched along with the intake. I suspect that I will be port matching the new exhaust manifolds to the heads too. The future build will produce 400 to 450 HP and the old headers are getting tossed. No more headers for me. I do have the stock manifolds in the attic, but I am thinking..."why not upgrade?"

Given that the upgrade poses no problems...I have to decide which collector size, 2-1/4" OR 2-1/2" ????

The old exhaust is soon to be cut off and tossed, so new exhaust will be put back on (someday). Which do I go with? Pros and cons, one over the other? What questions should I be asking myself to help make this decision?

My gut says go with the larger...bigger is better right? I thought I'd throw it out to the group before I place the order in case my gut is out of calibration today.
 

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I am thinking that I want the Ram Air/HO exhaust manifolds to put on my 67 with 670 heads. The heads have been port matched along with the intake. I suspect that I will be port matching the new exhaust manifolds to the heads too. The future build will produce 400 to 450 HP and the old headers are getting tossed. No more headers for me. I do have the stock manifolds in the attic, but I am thinking..."why not upgrade?"

Given that the upgrade poses no problems...I have to decide which collector size, 2-1/4" OR 2-1/2" ????

The old exhaust is soon to be cut off and tossed, so new exhaust will be put back on (someday). Which do I go with? Pros and cons, one over the other? What questions should I be asking myself to help make this decision?

My gut says go with the larger...bigger is better right? I thought I'd throw it out to the group before I place the order in case my gut is out of calibration today.
I think in this case bigger is better with that HP, good luck finding them as a couple members have been waiting many months for them sorry to say. If you're looking at exhaust systems I did the 2.5 polished stainless from Pypes, went together great just saying.
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I think it would be a great upgrade from stock manifolds and without the hassles of headers. They function and fit well on my 467 in my 65. BUT, finding them is difficult right now. I suggest you buy what you can find and go with larger diameter if available.
 

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Discussion Starter · #4 ·
I haven't thought about exhaust pipes yet. Even the manifolds are a couple years away from being needed. I'm trying to order them now so I have them later. Baaad, your Pypes look fantastic! Your trying to spend my money on stainless steel...it's not hard to do. I had seen that the 68 and newer exhaust mani's were hard to find...are the 67's in sort supply too?

Part of me says get the 2-1/2 mani's and that way if I cheap out and don't get mandrel bent exhaust, the 2-1/2 OD pipe will be reduced down, but not as much as the 2-1/4" would.
 

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I haven't thought about exhaust pipes yet. Even the manifolds are a couple years away from being needed. I'm trying to order them now so I have them later. Baaad, your Pypes look fantastic! Your trying to spend my money on stainless steel...it's not hard to do. I had seen that the 68 and newer exhaust mani's were hard to find...are the 67's in sort supply too?

Part of me says get the 2-1/2 mani's and that way if I cheap out and don't get mandrel bent exhaust, the 2-1/2 OD pipe will be reduced down, but not as much as the 2-1/4" would.
Thanks, I got the whole system through Summit on some sale, it wasn't too bad I think under 1500.00/w free shipping end to end with clamps 👍
 

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I am thinking that I want the Ram Air/HO exhaust manifolds to put on my 67 with 670 heads. The heads have been port matched along with the intake. I suspect that I will be port matching the new exhaust manifolds to the heads too. The future build will produce 400 to 450 HP and the old headers are getting tossed. No more headers for me. I do have the stock manifolds in the attic, but I am thinking..."why not upgrade?"

Given that the upgrade poses no problems...I have to decide which collector size, 2-1/4" OR 2-1/2" ????

The old exhaust is soon to be cut off and tossed, so new exhaust will be put back on (someday). Which do I go with? Pros and cons, one over the other? What questions should I be asking myself to help make this decision?

My gut says go with the larger...bigger is better right? I thought I'd throw it out to the group before I place the order in case my gut is out of calibration today.
I believe that I may already have a post on this, for a 67 with 670's.
 

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Discussion Starter · #9 ·
Army, if this is the tread you are referring too....


It really dived into the sound of the exhaust more so than the 2-1/4" VS 2-1/2" options...I'm more into quiet without a loss of power. AS IF those two things can find a place to agree...lol!

I'll be buying the 2-1/2" mani's per the advice so kindly given on this thread. Thanks folks!
 

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Army, if this is the tread you are referring too....


It really dived into the sound of the exhaust more so than the 2-1/4" VS 2-1/2" options...I'm more into quiet without a loss of power. AS IF those two things can find a place to agree...lol!

I'll be buying the 2-1/2" mani's per the advice so kindly given on this thread. Thanks folks!
Yes, that's my exact point, my car is quiet... Two people can have a conversation, without yelling, while going 85mph and taching 4000 rpms.
 
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