SNEAK PEAK - sidepipe upgrade

[canuck1]

I've been playing around with modifying my sidepipes for a while now. It started off with just wanting to quiet them down (a little). I bought a set of Breeze Quietpipes to get a noise level baseline. I determined that they are TOO quiet for my liking and not appropriate for my engine's needs (too restrictive). I set the Quietpipes aside and decided I would simply get a 'better' muffler for my FFR sidepipes but also began collecting a lot of information from all the experts here about improving exhaust flow as well. So, what started out as a simple muffler replacement job has gone down an interesting road, but I LIKE experimenting!!!

Here are a few quick iPhone photos to show where I'm headed. Keep in mind this is still mostly bare steel and unfinished. Welds are still a little rough but it'll all get tidied up after final assembly.

If you've ever taken the time to look closely at the FFR sidepipe you've probably noticed the divot in the center of the flange which no amount of silicone would seal. This internal exhaust leak between primary tubes is the source of a great deal of turbulence and flow restriction. I had the flange surface welded in the center and then ground flat just like it is on the headers they attach to.

Starting point, header/sidepipe flange:




The FFR collector (lower in the pic below) is a severe bottleneck when you consider the abrupt transition from the ample primary tubes in to the collector. I had the old unit cut off and welded on an off-the-shelf formed collector from Hooker which makes a much smoother transition.

Next step, improve collector:



Aside from the abrupt transition provided by the FFR collector, there is no transition cone between the 4 tube's junction to aid in reducing flow turbulence as the exhaust finds it's way through the collector and in to the muffler. I had a pre-fabbed transition cone added and I'm happy with how it looks!

Stock FFR collector looking from muffler end towards primary tubes. Note lack of transition cone (credit - Classic Chambered Exhaust):



The arrow points the way out. Transition cone installed:



I know I'll have people who don't agree with the muffler style I've chosen but I did quite a bit of research and settled on longer, Magnaflow brand glasspacks which use a non-fiberglass type of thermal insulation and a straight through, perforated core rather than the louvered core the FFR muffler uses. I'll post a core pic later but this one demonstrates the difference in length.

The muffler (size DOES matter):



I'll fit the primary tube/collector section on my car, align muffler and tack in place, followed by (shortened) tip section. Then back to TIG welder for final welding and clean up. Hoping to have them coated soon afterwards, but may live with paint for the summer if there are any delays.

Let me know what you think???

Sean

[2FAST4U]

Very nice!! Looking forward to hearing the sound

[dallas_]

That is very interesting. Please keep us posted.

[Howff]

Nice! Keep pics comming.

[ROADRACER83]

You read my mind. I was going to do something very similar to mine to clean up the transition to the side pipes and go to a different muffler. You did a nice job and used good sense to do this upgrade. Please forgive me for blatantly stealing your ideas and copying your pictures into my FFR great ideas folder.

Ron

[canuck1]

I collected a few more pics so you can all get an idea just how crazy I am!

I borrowed this from Classic Chambered Exhaust's website because I had such a hard time getting a shot of my own (FFR) muffler core. I measured the flowpath at +/- 2 1/8" between the spiral louvers.

Standard FFR muffler core. Note the spiral louvers which are oriented facing towards the rear:



Here's another for comparison (I borrowed this pic from forum member Bob Cowan).

Classic Chambered Exhaust 3" compared to FFR 2 1/8" spiral louvered core muffler:



Bob Cowan installed a longer but also larger flow path spiral louvered core muffler and got good performance and sound results. I am approaching it a little differently, also with a longer, but perforated (not louvered) core glasspack and a relatively smaller flow path.

My theory is that, with the same 4" outer body diameter, the 2 1/4" flow path Magnaflow muffler (below) should have more packing than a bigger flow path muffler of the same outer diameter? Maybe quiet enough (given the new muffler's length) with less turbulent exhaust flow?

Magnaflow perforated core glasspack:



I don't know (obviously) whether my goal of moderately reduced sound is realistic or not, but I'm at least fairly certain I'll pick up a few hp in the process!?

Sean

[CraigS]

Can't wait to hear how you like your setup.I have recently installed new FFR side pipes(w/ a little additional length and a turndown angled down at 45 deg) in place of my 19000 mile worn out FFRs.It's definatley less noise but, of course, no performance change. I'd like to get another similiar step reduction in noise and help or at least not hinder performance. What is your thinking on your packing lifespan vs fiberglass which we know will burn out?

[GWL]

Great work, keep it up.

George

[canuck1]

Originally Posted by ROADRACER83

You read my mind. I was going to do something very similar to mine to clean up the transition to the side pipes and go to a different muffler. You did a nice job and used good sense to do this upgrade. Please forgive me for blatantly stealing your ideas and copying your pictures into my FFR great ideas folder.

Ron

No problem at all Ron! I am honored.

Originally Posted by CraigS

Can't wait to hear how you like your setup.I have recently installed new FFR side pipes(w/ a little additional length and a turndown angled down at 45 deg) in place of my 19000 mile worn out FFRs.It's definatley less noise but, of course, no performance change. I'd like to get another similiar step reduction in noise and help or at least not hinder performance. What is your thinking on your packing lifespan vs fiberglass which we know will burn out?

All manufacturers seem to have their own theories and data on why their product is best etc. but I honestly have no idea whether the Magnaflow's will last as long as any other glasspack or not. They claim the thermal insulation is more durable than traditional fiberglass packing They also claim that the straight through design promotes a longer wear life vs. louvered cores but won't go so far as to tell you how many miles you should expect to get. ALL glasspacks burn out as far as I'm concerned and should be viewed as a wear item. While they are obviously longer lasting than glasspacks, I just haven't liked the tone of the sound I've heard from some of the steel muffler/insert options (Car Chemistry, Lobacks, 'turbo' mufflers or the like).

P.S. My total parts expense in this project is as follows:

- Hooker collectors (Summit) $50/pair
- stainless steel transition cones (Cone Engineering) $40/pair
- Magnaflow 26" long glasspacks (local shop) $80/pair
- grand total $170 + welding costs, shipping and (later) recoating

I'm lucky enough to have some good welders who work for me.

Sean

[KC Wildcat]

Wow, that is a very affordable retrofit!

[Dan Babb]

Adyno pull with your pipes and the stock ffr pipes would be cool to see.

Nice work.

[canuck1]

Here's a couple mock-up photos to give you an idea of what it will look like as well as how it fits for overall length. Keep in mind I went from a 22" long muffler to a 26" long muffler and I haven't shortened the tip at all yet:





I know many have suggested turning the tip slightly downward helped reduce sound, I'm yet to be convinced it's worth it enough to make me give up the 'look' that goes with the large oval tip opening facing outward.

My original FFR sidepipe for comparison:



With heat shields installed:



My heat shields would still just cover the new muffler body. They are 27" long and the muffler is 26".

Sean

[jlkendri]

i ended up using the ffr sidepipes but cut out the glasspack and welded in an auger style race muffler. Looks like glasspacks from the outside. there is nothing in there to wear out, all metal. I have heard the glasspacks get louder with age since they start getting packed with carbon. Sorry but i don't remember the manuf. Might be another option to look into.

[canuck1]

Originally Posted by jlkendri

i ended up using the ffr sidepipes but cut out the glasspack and welded in an auger style race muffler. Looks like glasspacks from the outside. there is nothing in there to wear out, all metal. I have heard the glasspacks get louder with age since they start getting packed with carbon. Sorry but i don't remember the manuf. Might be another option to look into.

I've looked at a couple different auger type insert mufflers (similar to the inserts Gordon Levy uses in his header/sidepipe packages). It's a great idea, but I actually prefer the tone of glasspacks. The few metal insert mufflers I've heard all seem to have a bit of a hollow, tinny sound that goes along with the lower noise level.

Yes, ALL glass packs do wear out, but I figure in the 4 years or so of driving miles I put on them will probably mean I want to re-coat them anyways. With some luck the glasspacks will last until I'm ready to touch-up or recoat the pipes. The glasspacks themselves are actually quite inexpensive.

Sean

[dv/dt]

Hi Sean,
Looks great so far! Just make sure the the side mount is adequately mounted to the pipes. On my DNA's the mount on one side picked up the internal angle iron baffles (they spiral down the pipe) and the welds have held well. On the other side I was not quite as lucky and the mount only picked up the sheet metal of the pipe. It eventually ripped a hole in the side of the pipe. The repair (holding so far) was to weld on a larger, thicker pad of SS and weld the mount to that. You may want to consider something similar for yours.

All the best, Rod

[Ray]

"I know many have suggested turning the tip slightly downward helped reduce sound, I'm yet to be convinced it's worth it enough to make me give up the 'look' that goes with the large oval tip opening facing outward."

I've thought of rotating them a bit also. Not much, maybe 15-degrees or so.

Ray

[Big Blocker]

Ray,

When I rebuilt my sidepipes a year ago or two, I angled my tips down by 15° . . . the Db meter says I knocked 2 Db off my left ear. I will admit that I also replaced my FFR mufflers with a different model that has a larger internal baffle tube, 3" compared to the original 2-1/4". Not absolutely sure the newer, larger internal pipe (which should be louder) isn't contributing to the new sound level, but my ears say yes. I like to think the 15° down allows the new sound to aim down-n-out, instead of just out, where my ears can pick it up more.

I'll be at HB again this year, you're more then welcome to "see" the look.

Doc

[canuck1]

Originally Posted by dv/dt

Hi Sean,
Looks great so far! Just make sure the the side mount is adequately mounted to the pipes. On my DNA's the mount on one side picked up the internal angle iron baffles (they spiral down the pipe) and the welds have held well. On the other side I was not quite as lucky and the mount only picked up the sheet metal of the pipe. It eventually ripped a hole in the side of the pipe. The repair (holding so far) was to weld on a larger, thicker pad of SS and weld the mount to that. You may want to consider something similar for yours.

All the best, Rod

Thanks Rod,

Because I'm going to be putting my heat shields back on, I've thought about not welding any mid-pipe support on. Instead, I think (?) I can use a 4" t-bolt clamp combined with my factory rubber-supported hangers to do the job (that's how the heat shield is clamped to the muffler at each end). I'll have to fab some kind of simple bracket between the clamp's bolt and the frame hanger, but it will all be hidden behind the heat shield. Worth a try.

Originally Posted by Ray

I've thought of rotating them a bit also. Not much, maybe 15-degrees or so.
Ray

I'll definitely play with how a small tip rotation looks before tacking anything together.

Sean

[LuisO]

Sean that is very nice man...looks like a great project for me..l hate the loud clackety sound of FFR side pipes.

You mind posting part number for hooker and magnaflow? also the shields, who are they from?

Thanks.

[emac]

Great fabricating. Did you consider car chemistry inserts? My car isnt finished but I was thinking of something to quiet it down and came across this thread.

Silencers in J-pipes

[canuck1]

Originally Posted by LuisO

Sean that is very nice man...looks like a great project for me..l hate the loud clackety sound of FFR side pipes.

You mind posting part number for hooker and magnaflow? also the shields, who are they from?

Thanks.

The Hooker header collectors came from Summit:

http://www.summitracing.com/parts/HOK-11552HKR/

(keep in mind they were shortened and tapered in a little to match the input funnel on the muffler end)

The transition cone or 'merge bullets' came from Cone Engineering (you can actually order a pretty nice merge collector kit from these guys too):

Exhaust Collector Components, Stainless Steel Collector Components, Turbo Stars & Bullet Components

The Magnaflow mufflers are part number 18146 (with the 2.5" inlet neck cut off and funnelled to match collector end):

MagnaFlow Exhaust Products - For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles

I haven't done a thing yet though other than putting some pieces together. I'm fairly confident it will be better flowing than the FFR sidepipes and hopefully produce a lower, mellower tone, but I'll believe that when I hear them.

My heat shields are from forum member Drummermike.

Originally Posted by emac

Great fabricating. Did you consider car chemistry inserts? My car isnt finished but I was thinking of something to quiet it down and came across this thread.

Silencers in J-pipes

I can hardly take credit for the fab work. I don't have those welding skills. I am lucky enough to be able to keep a few welders busy year round at work who like the odd 'special' project .
I am using 4 into 4 headers, so I don't have the option of a J-pipe insert.

Sean

[CraigS]

Don't worry about a bracket. I have had no hanger on my FFR pipes for 20,000 miles w/o problem. These things are so strong that you can jack up the car by the pipes. I discovered this when I was trying to adjust the height of my pipes years ago. I jacked the low side up till both wheels were off the ground and made about 1/4 inch change. I jumped up and down on the high pipe and made even less of a change.

[canuck1]

Originally Posted by CraigS

Don't worry about a bracket. I have had no hanger on my FFR pipes for 20,000 miles w/o problem. These things are so strong that you can jack up the car by the pipes. I discovered this when I was trying to adjust the height of my pipes years ago. I jacked the low side up till both wheels were off the ground and made about 1/4 inch change. I jumped up and down on the high pipe and made even less of a change.

But Craig, I've seen your picture and you could jump up and down all you want, it wouldn't make any difference !



To be honest, I know I've added both length and weight to the basic FFR sidepipe setup and the welders who put it together both suggested that I DO incorporate some kind of support. I'll respect their suggestion, as the last thing I'd want to do is bring it back to ask them to repair a crack if I didn't!

Sean

[Big Blocker]

CraigS,
Consider yourself one of the lucky ones . . . you are one in five thousand.

To everyone else, you need to support the sidepipe about half-way down the muffler area, just where FFR provides (suggests) a hanger mount.

True, the pipes are extreamly robust and will take a real beating but over time, heat cycles and the constant bouncng up and down during even normal driving will take its toll at the header flange at the heads. That is where the greatest amount of "twisting" happens. First sign is small cracks at the flange welds and that "always popular" ticking noise everyone asks about on this forum.

Do yourself a favor up front, install a hanger.

Just my 2¢

Doc

[canuck1]

UPDATE!

I apologize for taking so long getting this project done. Work's been busy and we are getting ready to move in to a new house. Doesn't leave me much time to spend in the garage.

I discovered (not surprisingly) that modifying my sidepipes wouldn't fix the fact that my passenger side pipe has always required a spacer to get it out away from the body. My problem is right at the inside radius of the primary pipes as the sidepipes exit the body cutout. They actually touch the side of the body just aft of the cutout. I have always run a 3/8" spacer there to provide clearance. I just thought I would point out a difference between the type of spacer I have been using and the wedge/spacer most commonly available from forum vendors:



The one on the right is the standard spacer/wedge you can buy from various forum vendors to help with sidepipe alignment problems. Notice how the entire center section is open, which allows gases from the 4 primary pipes to mix and create turbulence which amounts to a flow restriction and lost hp.

The one on the left (which looks kind of like a sidepipe gasket) is actually a 3/8" thick steel spacer). This 4 hole spacer (I didn't need a wedge to correct alignment) keeps the primary tube gases separate until they hit the collector where they have room to expand and are directed into the muffler opening. A 4 hole spacer like this can easily be cut on a waterjet (using an sidepipe gasket as template) for around $30 (cheaper if you make more). You will get the most benefit if you also fill in the center hole/divot in the middle of the FFR sidepipe flange (as I did as one of the first steps in this upgrade). This divot also allows for exhaust gas mixing and flow-restricting turbulence.

Here's my welder Kevin squeezing in to my garage to tack the mufflers on to the new collector section (remember I said I was MOVING... garage is piled with junk to go to the dump right now ):



Yes, I did remember to disconnect my battery and ECM! The car is actually on 4 jackstands with wheel ramps as backup only.
We levelled the sidepipes, keeping them nice and straight in line with the adjacent body sides then Kevin tacked them in 3 places:




A peak at installed mufflers before tips fitted:




I then used an angle finder to orient the exhaust openings (I settled on rotating them 20 degrees down) and marked each muffler and tip with a felt pen before removing the collectors/mufflers for finish welding.

New sidepipes and mufflers! You can still see my felt pen lines on the passenger side pipe. No hanger mount welded on. I have another solution for that issue I'll post about later. I cut 2" off the tips (12" down to 10"), well, just because I thought it looked better!?



If I'm lucky I'll get them on tonight!? Won't have a chance to start it until the weekend though (still have my power steering rack off). Hope a few new pics will do for now!? I can't believe how many people have contacted me asking what's taking so long. Doh!!

Sean

[thewallet]

Sean, just sent you a PM.

Wade

[thebicman]

Looking at your pipes and the collector. How hard was it to weld them together? Four round pipes into a squarish opening, without leaks.

[canuck1]

The input end of the collector comes formed to fit around the primaries. If you're asking me how the center gets welded, well I have no answer. I asked the question (curious minds want to know) and the welder just smiled and said... 'secret'!
I still don't know .

He did say "make sure you test them before you coat them!"

Sean



Sent from my Autoguide iPhone app

[Cobra3657]

Great project! Always cool to see people breaking out welders and sheet metal saws on these things.

You may have seen it, but i did my own custom sidepipes a couple years back. Here's a link to the thread:

Custom Sidepipes - A Different Approach

I used a hybrid, rebuildable glasspack with a small baffled section made by Burns Stainless, 5.5" outer diameter and a 3" straight-through non-louvered core. It's all stainless and I did the TIG'ing myself. It was a really fun project. Like you, my original goal was to improve the exhaust a little and quiet it down a touch. I was not successful with the latter, but I do really like how the pipes turned out. All the details are in the thread, but I was able to draw two big conclusions from the project:

1) Quiet = restrictive. In my experience there's just no way to quiet down the pipes without adding restriction. The pipes I ended up with are about as loud as the standard ones, but much deeper-sounding and less raspy. I think if I decide to try to quiet it down any more, I'll just add some catalytic converters.
2) Glasspacks are actually pretty darn good mufflers, especially when they can be rebuilt. Any baffled design that doesn't use some form of packing is likely to be either much more restrictive, or have a very high-pitched raspy sound, or both.

[Rare Iron Eric]

Well Sean - how did they turn out??? Curious to see if the smooth perf core mufflers offered an acceptable noise level/tone. They should be a little louder than mine.

-Eric