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I have the Ram Air Resto Cast iron headers/HO Manifolds for D port heads. Your car won't get any louder, thats for sure But if you use the Remflex gaskets, you will NEVER have a leaky manifold again. I installed prior to my rebuild so I know I did it with motor in car, Need to remove motor mount bolt, jack up side etc. etc.and that last bolt on driver side sucks b**ls. I had them coated and everything then hooked them to Pypes ball&socket downpipes. If you want it louder, why not bite the bullet and go back to 70s and glass packs? they're a bit ratty but loud as F when you WOT.

In any case - I certainly recommend the RamAirResto manifolds. And am also jealous of the 5 speeds. I'll just live with my AutoGear/Muncie clone 4 sp and 3.90 rear gear. oh darn right? ;)
 

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Discussion Starter · #22 ·
I know you don't want turndowns, but that is what I have on my car and it is LOUD (to the point I created a post a while back asking about side exhaust in front of the wheels).

Mild 400, Hedman long tube headers, standard H crossover, 2 chamber flowmasters, turndowns right in front of axle. LOUD as F. What I'm missing is the nasty lope you probably just got from your cam swap.
If you look at my ugly motor thread, you'll see that in 3 evenings, I:
  1. Stripped the engine of the valve covers, valley pan, intake, timing cover, water pump, pulleys, cam, lifters, and rockers.
  2. Blasted and cleaned it all.
  3. Painted it all.
  4. Reassembled it all with a new cam, adjusted the valves, fixed leaks, fixed stripped holes, and corrected a misinstalled cam retainer!
If I skipped the paint work, I couldve done it all in one evening!
 

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Discussion Starter · #23 ·
You did the cam swap? You don't like it?

You can get a 2,500 stall converter for cheap. You could have the larger full size converter in that trans which will make it soggy/slow. Unless you know the trans is the born with TH-400 and it still has its original converter, you might want to just swap for a better converter until you can do the TKO or 4-speed swap.


Put one in my brother's car - worked great. Just fill out the form. $325.00 for the TH-400. Of course TCI and B & M are good converters as well. I have said this before, my boat of a '73 Fury & 360CI 2 Bbl, 180 HP/2.71 rear gear has a factory "loose" 2,500 stall converter. You would be impressed when I mashed the gas. Puts the engine up into its lower power range and out of the gate I go. If I ran an automatic, I would have to have a 2,400-2,500 stall converter just for the smiles.

But, you may have more power than you realize as a broader torque curve can be deceiving because the power comes on very smooth rather than explosive and track results do prove this.
Thanks for all of your help and guidance on the project, Jim. Yep, cam swap is done! Can't say that I have any regrets, because the cam retaining plate was installed wrong, so it was starving for oil. Plus, I had a few leaks, a few stripped bolt holes, poorly adjusted valves, and a seriously deficient paint job... all of which I corrected!

As you told me to expect, my power band moved up a bit from the new LSA... So it's a little doggy off the line, but roll on power and exhaust note is an improvement. I was just hoping for a more dramatiic improvement on both fronts.

All that being said... the TKX or a stall conv will help... And it was serious progress on many fronts. Ill get there!

Within the last month on this forum, I learned to install a cam, adjust valves, build a dizzy, set a timing curve, and spot and correct a serious engine flaw. So even with my quietish exhaust, it's still a solid victory.
 

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Discussion Starter · #24 ·
I have the Ram Air Resto Cast iron headers/HO Manifolds for D port heads. Your car won't get any louder, thats for sure But if you use the Remflex gaskets, you will NEVER have a leaky manifold again. I installed prior to my rebuild so I know I did it with motor in car, Need to remove motor mount bolt, jack up side etc. etc.and that last bolt on driver side sucks b**ls. I had them coated and everything then hooked them to Pypes ball&socket downpipes. If you want it louder, why not bite the bullet and go back to 70s and glass packs? they're a bit ratty but loud as F when you WOT.

In any case - I certainly recommend the RamAirResto manifolds. And am also jealous of the 5 speeds. I'll just live with my AutoGear/Muncie clone 4 sp and 3.90 rear gear. oh darn right? ;)
Ive had two sets of straight through glass packs and it was still quiet. Now on Flowmaster 40's, which are typically considered obnoxious! My old 67 had the same setup with bullet mufflers and it was much louder... Which is why I was thinking that the 4/7 cam was partially responsible (and it was). I'm going to disconnect the tail pipes and see what the diff is. Then I'll try opening the headers.
 

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Ive had two sets of straight through glass packs and it was still quiet. Now on Flowmaster 40's, which are typically considered obnoxious! My old 67 had the same setup with bullet mufflers and it was much louder... Which is why I was thinking that the 4/7 cam was partially responsible (and it was). I'm going to disconnect the tail pipes and see what the diff is. Then I'll try opening the headers.
Some times I get change back from my 2 cents but here it is anyway. Full length Hedman headers on 67 400 with 670 heads ,Cam Motion custom grind cam with 112 LSA and little overlap. True duel exhaust,
no crossover H or X pipe. 2.5 " stainless exhaust with Flowmaster 50s exiting in front of rears like NASCAR. The exit is straight cut. I've read that an angle cut will quiet things down. It's loud but not Barney pull me over in town loud. At wot very loud. Have you considered chambered exhaust?
 

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Discussion Starter · #26 ·
Some times I get change back from my 2 cents but here it is anyway. Full length Hedman headers on 67 400 with 670 heads ,Cam Motion custom grind cam with 112 LSA and little overlap. True duel exhaust,
no crossover H or X pipe. 2.5 " stainless exhaust with Flowmaster 50s exiting in front of rears like NASCAR. The exit is straight cut. I've read that an angle cut will quiet things down. It's loud but not Barney pull me over in town loud. At wot very loud. Have you considered chambered exhaust?
I've considered a lot of different things, but Im perplexed because Ive had many similar cars, with less performance, which were much louder. Not much is louder than a Flowmaster 40, which is whats on there now.

It's one thing to buy a $800 exhaust, but it gets pricey when you start butchering and swapping it out every 2 months. Three sets of mufflers, 2 sets of tips, 2 sets of tails, and 2 different crossovers, in one year.
 

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Some times I get change back from my 2 cents but here it is anyway. Full length Hedman headers on 67 400 with 670 heads ,Cam Motion custom grind cam with 112 LSA and little overlap. True duel exhaust,
no crossover H or X pipe. 2.5 " stainless exhaust with Flowmaster 50s exiting in front of rears like NASCAR. The exit is straight cut. I've read that an angle cut will quiet things down. It's loud but not Barney pull me over in town loud. At wot very loud. Have you considered chambered exhaust?
I've been considering changing from turndowns to side exit in front of rear tires for a while now. Do you have pics you could post of where your tips are and how you routed unde the car?
thanks!
 

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My old 66 Lemans had side exits before the rear tires. They were louder than tails, for sure.
My old 66 Lemans had side exits before the rear tires. They were louder than tails, for sure.
No pics from under but I can tell you that the mufflers are more or less under the seats then pipes are angled out. They don't protrude the sheet metal and blow just past outer edge of tires. Sent twice by accident.
Tire Wheel Plant Vehicle Car


Tire Wheel Plant Vehicle Car
 

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Discussion Starter · #30 ·
Side exit looks good and Im sure it sounds good, too.

I was always told (and have preached without evidence for 35 years) that the further forward the mufflers were, the louder the exhaust would be. Therefore, header mount mufflers would be the loudest. This theory could be credited by the fact that my mufflers are under the back seat... However the vette seems to disprove that theory, since the mufflers are at the rear bumper.
 

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Discussion Starter · #31 ·
A few of you guys should throw some sound clips on youtube! I'd be seriously interested in hearing the differences. Here's mine with the 4/7 swap cam, which from what Ive been told sounded great when I got on it. I'll post one with te new cam, ASAP.
 

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Alright, this will seem like a really dumb question, but have you verified that when you push your gas pedal to the floor, you are actually getting full throttle at the carb. The reason I ask is that I recently installed new ACC Essex carpet in my car. I also got some really nice floor mats (made with the thicker Essex carpet). The combination of the carpet and the floor mats are limiting my throttle so that in order to get kickdown to happen, I have got to push REALLY hard on the pedal. I am going to have to cut the floor mat so it does not interfere with the gas pedal.
 

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I've considered a lot of different things, but Im perplexed because Ive had many similar cars, with less performance, which were much louder. Not much is louder than a Flowmaster 40, which is whats on there now.

It's one thing to buy a $800 exhaust, but it gets pricey when you start butchering and swapping it out every 2 months. Three sets of mufflers, 2 sets of tips, 2 sets of tails, and 2 different crossovers, in one year.

Hmmmmm. How old are you and how many loud exhaust cars did you think were really cool sounding - especially with wide open throttle?

Maybe its not the exhaust?????? LOL

An old man is concerned that his wife is starting to go deaf...

The old man goes to the doctor and says, "My wife can't hear very well anymore and I am getting worried. What should I do to help her?"

The doctor thinks for a minute and says, "First we need to understand how serious the problem is. Stand 25 feet away from her and ask her a question. If she doesn't respond, walk 5 ft closer and ask again. Repeat this until she can hear you and then let me know how far away you were standing."

The man is so concerned for his wife that he agrees to do what the doctor suggested. When he gets home, he sees his wife cooking in the kitchen. He stands 25 feet from his wife and says, "What's for dinner?"

The wife does not answer and he walks closer, "What's for dinner?"

The man does this 2 more times until he is standing only 5 feet from his wife. The man is now very worried and tries one last time, "What's for dinner?"

The wife looks over and yells at him, "I HAVE TOLD YOU 4 TIMES ALREADY, WE ARE HAVING LASAGNA!"
 

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Hmmmmm. How old are you and how many loud exhaust cars did you think were really cool sounding - especially with wide open throttle?

Maybe its not the exhaust?????? LOL

An old man is concerned that his wife is starting to go deaf...

The old man goes to the doctor and says, "My wife can't hear very well anymore and I am getting worried. What should I do to help her?"

The doctor thinks for a minute and says, "First we need to understand how serious the problem is. Stand 25 feet away from her and ask her a question. If she doesn't respond, walk 5 ft closer and ask again. Repeat this until she can hear you and then let me know how far away you were standing."

The man is so concerned for his wife that he agrees to do what the doctor suggested. When he gets home, he sees his wife cooking in the kitchen. He stands 25 feet from his wife and says, "What's for dinner?"

The wife does not answer and he walks closer, "What's for dinner?"

The man does this 2 more times until he is standing only 5 feet from his wife. The man is now very worried and tries one last time, "What's for dinner?"

The wife looks over and yells at him, "I HAVE TOLD YOU 4 TIMES ALREADY, WE ARE HAVING LASAGNA!"
:ROFLMAO:
 

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Okay... 1967, 400, 670 heads, Dougs Headers, 2.5 duals, Flowmaster 40's, no crossover.

My exhaust is embarrassing. It's a beautiful car so so it draws a ton of attention... and then I have ZERO oomph to back it up. Im on my 3rd set of mufflers, 3rd crossover, and now my last ditch effort was to swap the cam, which I did, and I got no where.

I don't want turn downs because I like the look of tail pipes exiting the rear, and I think that exhaust gas ahead of the axle isn't the best idea for me or the car.

I'm perplexed... My 70 vette with a 275 hp 350 and Turbo mufflers sounds like the hammers of Hell. My 67 GTO sounds like a 280z. Now to add insult to injury, it looks like I may have a stripped manifold bolt and it's leaking enough to blow out the gasket. If I have to remove the header to fix it, I would not put them back on.

Are the Ram Air manifolds available yet and can they be put on with the engine in?
Yes, RA manifolds are available and they can be installed with the engine in the car. It'll be harder to get the headers out than it will be to put them in.

When you say it has no "oomph" --- are you talking about how it sounds or that it doesn't have the power/performance it should?

BUT - I highly doubt that your exhaust is the source of the problem, if I understand you correctly that it's lacking power? Have you tried driving it "uncorked" (headers open) to see if that makes a difference? That's a whole lot easier than rebuilding your whole exhaust system, especially when you're not sure it's the cause of the problem.

Bear
my 70 has hooker headers 2 1/2 exhaust with flow masters sounds amazing may also be part of the solid lifter cam
 

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this summer I did a top end refresh, from a crower 60916 and 77 heads on a stroked 421, to a crower 60919 with kre d ports. Exhaust remained exactly the same, rare manifolds, 2.25 pipes and dynomax ultra flows. The sound changed a lot which I am chalking up to the heads and bigger valves. Oddly enough, not much lope, which I thought that cam was going to give me more lope. Suspect it’s the 461 ci that is moderating that cam for lope.
My point overall- other things beside exhaust can change the sound too.

 

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Here is a sound clip of mine. Yours sounds louder than mine which makes sense. Mine has a 461 with a Comp CE284H cam, 1.5 ratio rockers, factory cast manifolds (still waiting on the RARE manifolds to ship) and Pypes Race Pro mufflers (longer body 18").

 
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