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Discussion Starter #1
Got to meet Dave Feeney earlier today and see his MkIV. I thought my 15" wheels looked good until I saw those Goodyears! They look incredible.

It's the first time in a while that I've been up close to another FFR and hearing his confirms what I know about mine - my exhaust sound just isn't right.

His 347 is a low, threatening Rottweiler, come too close and I'll kill you sound with the perfect amount of lope on the idle.

In comparison, my 351 sounds an octave or more higher and the idle is more yappy Yorkie who wants to play. Both idling around the 850/900 range.

Differences? Well, other than the slight displacement difference, Dave has FFR stainless pipes and I have uncoated FFR raw steel pipes. He has a custom cam, my cam and engine is all stock. I have no specs, bought the engine/tran complete from an upgrading Backdraft and have no reason to believe it's not just all 'off the shelf' stuff.

Would a cam and exhaust setup change the tone of the exhaust that much? Mine's plenty loud enough, just too 'yappy'. :laugh2:
 

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FFCobra Craftsman
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Sound being so subjective it's hard to say exactly. Over the last couple of years there have been a few threads on quieting the FFR exhaust. I would read through them and any others you find. Try to find some common ground among all the different opinions. I know that I am quite satisfied w/ the spirals I have added to mine. You will see my thread somewhere in your search results.
 

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Discussion Starter #3
Craig, volume's not the issue, mine is plenty loud. I'm still a noob so I'll take it as loud as I can get it!

The issue is with the 'tone' of the exhaust, mine is too high. Completely agree, it's very subjective, but when hearing them side by side the difference is very obvious.
 

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Too Cheap to paint!
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Alot of the "tone" is generated by size, compression, and cam profile. The cam is the biggest factor.

My 331 (412 HP) has such a different tone than my old FMS 302 / 345 HP. Same block, heads, exhaust, carb, intake. The 331 has higher compression, custom roller cam, 27 extra cubes.
 
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I'll just double down on what Craig said. Getting the right tone is like searching for the lost ark. To be sure the state of the engine's development is an important factor, but after that the muffler takes over and can vary from eeeuwwww to wow. In my case I have a fairly stout Ford Racing 351 and went with the exhaust system that was all the rage at the time. When I fired it up for the first time, I cringed. Is that me???? "That sounds horrible" I thought. Eventually I had enough and replaced them with mufflers from Stainless Specialties. Huge improvement. Very deep, throbbing at idle. When I first started the car after the changeover my wife came running out to the garage yelling at me that I was shaking the whole house. Perfect! I was and still am happy.

What tipped me off to these was a buddy of mine with a Superformance came over after he switched to these from the standard Superformance mufflers and I just fell in love with them right there on the spot.

You need to verify the specs on your engine then listen to other cars with a similar setup and see if you like what you hear and go from there.

Frank
 

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I agree with Chepsk8. I monkeyed around a lot with my sidepipes and came up with only a small change in the overall noise level as well as a perceptible increase in torque but changing to a milder cam made most of the difference to the sound at idle. If you compare your friends cam and compression specs with your own, you might have a better idea where the difference lies.

What do you know about your current cam? Does it need to idle at 900 rpm? You can improve the sound quite a bit by pulling it down 100-150 rpm at idle, as long as the car remains drivable and doesn't stall easily. it's a cheap trick but might make you 'nastier'!? :surprise:

Sean
 

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Compression and overlap!!!! The comp gives you the angry pop and the overlap makes it want to come out and bite your face off?
 

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Discussion Starter #8
Unfortunately I know nothing about the cam in my setup - all I assume is that it's all very stock. Going back to the video that was posted by the seller, it sounds about the same on the 'donor' Backdraft as on mine, so that takes the exhaust out of the equation.

Sean - I agree that the idle does feel high, something I mentioned to Dave. I'll try that certainly.

Again, the volume of the exhaust isn't the issue, it's the 'nastiness' that Sean hints at. I want more muzzled Rottweiler and less Yorkie that wants to hump your leg.
 

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Master of my Build
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....................... Yorkie that wants to hump your leg.

Would love to hear a video of of your exhaust based on your description.>:)
 

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Discussion Starter #11
These are the videos that were posted by the seller while still in the Backdraft. I think it's fair to say the sound is a little different with the raw steel FFR pipes, but the underlying 'tone' is about right, as well as the idle speed.

Compared to Dave's 347, it's no contest which sounds better, subjective or not!
 

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Open the exhaust valve early for long exhaust duration. Grind it with tight lobe separation this creates lots of overlap for Rump Rump.

Two ways to get it in a street engine. Thunder style cams & custom ECU tune in the COYOTE.

Rolling Thunder Edelbrock, Thumper Competition Cams.
 

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Discussion Starter #13
Adjusted the idle to 600 - sounds better, but certainly not 'there'.

I'll also add that I've not had the carb tuned nor the timing checked since putting the engine in, so quite possible the timing is out which won't help. Need to get that done.

I'll spend a long time looking for where to stick a custom ECU, so it would appear that a custom cam is the audience favourite.
 

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IMO cam will make the biggest difference at idle.

The heads will make a big difference above idle.

Mine purrs like a kitten at idle. By 2200 it gets mean sounding. Stock 5.0 cam with aluminum heads. I debate changing the cam, but love the drivability.
 

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This is the first start (well technically the second start about an hour later) of my DART 347 with AFR heads and a COMP CAM custom billet cam. Jim at Fordstrokers spec'd the cam to give me the sound/lope I wanted to but also be streetable. Just turned 3000 miles this past week. Runs great. Specs from the cam card: Intake Duration @.050": 224, Exhaust Duration @ .050": 232, Intake installed at Centerline: 106, Lobe Separation Angle: 110, Intake Lobe Lift: .348, Exhaust Lobe Lift: .354, Gross intake valve lift: .556, Gross exhaust valve lift: .566. It's idling here at about 800 rpm.

Everyone always comments how good it sounds. I have to agree. The video gives a little bit of an idea. As best as the sound from the little Canon pocket camera can provide. Those are GAS-N pipes, which are a little deeper/mellower sounding than the FF pipes in my experience.

 

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Discussion Starter #18
I'm going to see if I can take her into a local shop tomorrow to be tuned and have the timing checked. I'll also attempt a video and do my best to capture the sound.

Ed - as good as yours sounds, and I know I'm listening to what your camera was able to capture so not a fair comparison, but Dave's wins over yours to my ear! His is a much deeper tone - more of a 'wump, wump, wump' kind of sound. ;-)
 

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Discussion Starter #19

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Ed - as good as yours sounds, and I know I'm listening to what your camera was able to capture so not a fair comparison, but Dave's wins over yours to my ear! His is a much deeper tone - more of a 'wump, wump, wump' kind of sound. ;-)
Wasn't trying to have a contest... Trying to give you an example of a sound with the actual cam specs that went along with it.
 
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