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.......... Are the mufflers and resonators the same between the Fleetwood and the wagons, or no?

I had the mufflers on my 94 Fleetwood deleted by a shop. I left the OEM resonators and cats intact. The car was obnoxiously loud. As a teenager, I loved it, but people always thought it had glasspacks on it.
Zero diff. between D- and B-bodies, except ~6" longer between cats and muff inlets. I've put a cheap Jegs/Summit H- kit on both of mine to take up the difference, and found the longest mufflers possible to take advantage of the room. My current hack-up is quite tame by any taste, but still want to cut in some Jones resonators in during a break in the action to increase the 'sophisticated refined deboner quiet power' tone. ;)

Edit: Apologies, didn't realiz responding to the bottom of first page. Grrrr:: And for reference to my hack-up, my sig could use the added detail that I used the old front 1/2 of a 2 1/4" s.s. SLP catback that was on my Impala SS, and feeding into nice big 2 1/2" and long Dynomax muffs and out to 2 1/2" Heartthrob OTAs and tails. Pretty much the opposite of performance scavenging, but I'm not timing my 1/4-miles and the sound pretty much gets lost in space. The resonators should do even more, and with theoretically nil to no restriction. Highly scientific I assure myself.
 

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My understanding:
H-pipe is usually for low RpM power, X-pipe is usually for high RpM power, though there are of course exceptions.
Not sure a Fleetwood V4P NEEDS an X-pipe, but it only hurts when you have to remove the entire exhaust to work on something under the car - otherwise, it's pretty kewl.
That's been a big +1 with everything I've ever read with actual measured results re: the X- v. H- socratic debating. As each consistently show both add like only 1 or 3 hp, then I think my tie-breaker being the H- is half to third the cost of an X- takes the cake. I'll take 'cheap' + .5 ft./lbs. more torque offline any day.

Perhaps picking nits, but there's a vid testing H- v. X-, but the cx-over on the H- is like 2' compared to the X-'es zero inches. Hmmmm. On my kits I retain oem exhaust at closest point ~2 1/2" ?
 
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Yah same here on that one in Post 17. I sent word to Gerry.
 
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1995 Cadillac Fleetwood Brougham
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I found an x-pipe at the yard today in the trunk of the Caprice, but it looked like 2.25" so I left it.
 

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Discussion Starter · #28 ·
Unfortunately, not all of the necessary parts are still available to build the Frankenstein setup.

Jegs sells a catback for our cars for about $350 or so. If you want to spend more, you can buy something from Pypes or Magnaflow.

You also have the option of getting a local shop to bend up some pipe for you.
Thanx for that info yea i did some google searches was lookin at Jegs but it said it didnt fit the car.
Uh... no.

At one point in time, there was an actual part list that came to an exact dollar total. Don't make me search.
youre right i have the thread saved
 

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Unless things changed, both Jegs and Summit sell the same Heartthrobs catback. The OTAs can get to be either a tough or 'no fit' depending on if/what rear stab bar is installed.
 
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Discussion Starter · #33 ·
Unless things changed, both Jegs and Summit sell the same Heartthrobs catback. The OTAs can get to be either a tough or 'no fit' depending on if/what rear stab bar is installed.
Hope im replying correctly dont wanna piss anybody off lol but thanx for the info yea i saw the Jegs setup and read on a couple threads about the OTA issues. Appreciate the help.
 

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Don't be afraid to go to 2.25" after the mufflers if you want a good sounding exhaust but also want to keep the drone down. I'm sure people are doing to give me a tisk-tisk-tisk and smh, but most people don't think about exhaust velocity and how it affects sound. There are many ways to deal with drone. Some complex methods (tuned J-Pipe), some muffler placement methods (resonators), and some methods using basic thermal/fluids dynamic flow engineering.

In summary, on internal combustion engines (that generate pulses in the exhaust stream) as exhaust velocity increases, pulse reflections and resonance amplifications decrease. What happens to exhaust as it leaves the engine and moves further from the headers? The exhaust cools. And what happens when gasses cool (rapidly as in an exhaust system)? The gasses need less volume. What does this mean? Well it means that you can keep the same exhaust velocity and flow with a smaller pipe and kill off the pulse resonance and reflections at the same time.

Years ago, me and a friend embarked on a mission to kill drone on his Caprice. Trying to learn from mistakes I made on mine with the 2.5" ATR system (no longer available). We ended up with 2.5" from the headers to the X-pipe, then to the mufflers (I think his were Clear Image mufflers, but that was a long time ago). This is where 2.5" counts because the gasses are hotter but in the process of cooling.

Then we used 2.25" OTA, straight out under the bumper. No resonators. Zero drone. Really nice rumble at idle. The 2.25" reduction at the mufflers and over the axle and out the back was the trick due to the increased exhaust velocity. With a pure 2.5" system, including my own Caprice with no resonators, the drone was unacceptable. I tuned out some of my drone with straight pipes out under the bumper (turndowns make it worse). But I was so happy with his results, I planned to delete my 2.5" ATR resonators and replace the OTA pipe with a 2.25" system like his. The problem is that my ATR system is bulletproof. 150K miles later, I haven't touched it in 20 years. I just live with the drone.
 

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A PERFECTLY mandrel-curved 2.25" cat-back exhaust system would not be restrictive of up to 457 horse.
So sayeth David Vizard. Emphasis on no restrictions.
A kinked or crimped 2.25" pipe is at least as bad as a mandrel-curved 2.00" pipe.

2.50" pipe feels like a safeguard against restrictive kinks & crimps. Drone is the side effect of the compromise.
 
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Funny seeing my 2013 post in this thread (# 29), but I still have that set up. I did replace the DynoMax OTA (PS) pipe with another one because it rusted out at the bend coming right out of the muffler. Probably could have had a muffler shop fix it but just bought another 2 1/2" one at Autozone for around $30. The Dynomax OTA pipes are generally NA but do come up occasionally. I bought the DS when it did at AZ

The stock SS exhaust was 2 1/4 stainless, including CATS. My replacement CATS are 2 1/2" so my entire exhaust is 2 1/2

My "Frankenstein" set up originally was a full DynoMax CAT back I put on in 97....but as mods evolved it became what it is now (post 29)

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A PERFECTLY mandrel-curved 2.25" cat-back exhaust system would not be restrictive of up to 457 horse.
So sayeth David Vizard. Emphasis on no restrictions.
A kinked or crimped 2.25" pipe is at least as bad as a mandrel-curved 2.00" pipe.

2.50" pipe feels like a safeguard against restrictive kinks & crimps. Drone is the side effect of the compromise.
+1. And the stock exhaust our cars have a nasty restriction right after the cats under the floor pan. Not ideal. And not a good comparison to a high quality 2.25" system.

Generalizing a restriction is one thing. And easy to quantify for explanation. But understanding where we can get away with a smaller pipe (restriction) is another.

It really does depend on where the restriction is. Close to the engine, where the gasses are hottest and need most volume, yes, you want free flowing. And this is why a short exhaust on a race car performs better. Once we get through mufflers and OTA on our big cars, we enter the area of significant diminishing returns with a 2.5" system. My point is that if you can find good/cheaper 2.25" when assembling parts, AFTER THE MUFFLER, go for it. Won't hurt, even if badly bent, the flow in the system won't see a difference in restriction that far back between 2.5" and 2.25". And you benefit from less or no drone on the street. Win/win.
 

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Discussion Starter · #39 ·
Funny seeing my 2013 post in this thread (# 29), but I still have that set up. I did replace the DynoMax OTA (PS) pipe with another one because it rusted out at the bend coming right out of the muffler. Probably could have had a muffler shop fix it but just bought another 2 1/2" one at Autozone for around $30. The Dynomax OTA pipes are generally NA but do come up occasionally. I bought the DS when it did at AZ

The stock SS exhaust was 2 1/4 stainless, including CATS. My replacement CATS are 2 1/2" so my entire exhaust is 2 1/2

My "Frankenstein" set up originally was a full DynoMax CAT back I put on in 97....but as mods evolved it became what it is now (post 29)

View attachment 200325
View attachment 200326 View attachment 200327
Yeah i saved that old post for a reference, great pics too.
 

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You likely came across my setup in your search, but it's loud and i like it.
200329


and vid of the install

-ALF out.....
 
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