Hi all, I just installed thorly 376Y1 tri-y headers after reading how well they fit (and they fit quite well). Also decided to go with the Magnaflow 2.5" dual exhaust system (15896) primarily for the stainless material and great price. I had thought (?) that overall fitment was pretty good on the magnaflow systems, but I'm running into some issues...

1) At the front of the X-pipe, the magnaflow system has a slight bend up or down (depending on how the X-pipe is installed). Looks like the pipe should bend down, but with this puts the pipe a bit too low for the thorleys. I end up having to install an awkward bend down then back up to mate up with the headers. (I suspect with "normal" headers that are 1.5-2" lower, the pipes would match up well). Other option is to install the X-pipe with the bend "up" which is a much straighter shot to the headers, but then the lowest part of the car is exactly at the "X" on the X-pipe. Neither seems quite right...

2) I cannot seem to get the tailpipes to come straight out the back. Seems like the bends are off and both tips angle towards the center of the car a good amount. This just looks silly (and shouldn't be specific to the thorleys...). The CHP install here: (http://www.chevyhiperformance.com/tech/engines_drivetrain/exhaust/0607ch_1969_camaro_muffler_installation/)
actually looks like it has a bit of the same issue.

Any thoughts?

I will be looking forward to the input on this as this is the exact combo I plan on installing.

Maybe I'll sell you my magnaflow exhaust cheap :)

Found this while searching:
http://www.camaros.net/forums/showthread.php?t=67834

Looking like I need to contact Magnaflow and complain, and have them tell me I'm screwed. Then either modify the Magnaflow to fit or sell it at a loss and get something else (I'm tending towards the latter and using Flowmaster american thunder with Borla mufflers). Unhappy camper.

FWIW, it looks like the Magnaflow tailpipes are indeed bent to "stock" specifications for 67/68, but it would need an offset in, offset out muffler to make this work. Supplied mufflers are ofset in, center out, which makes the pipe bend funny at the exit...

Well, ended up getting rid of the Magnaflow and picking up the Flowmaster 2.5" American Thunder system (17139) and using Borla Mufflers (2.5" offset in, center out 40653). Fit MUCH better than the Magnaflow system for my car (69 coupe, 307, ST10 manual, thorley 376Y1). I still need to fine tune things a bit and get the system welded up, but so far, so good. Sounds good with the Borlas (quiet until you get on it, then sounds nice). Clearance between the head-pipes right after the Thorleys and the trans crossmember is a little tight, but works. I also had to tweak the H-pipe (widen the back by tugging on it a bit) and I'm gonna have to adjust the hangers a bit, but nothing hits or rubs :)

Overall, you can barely see the system below the subframe and everything tucks up really tight. Slash cut stainless tips come out straight with good clearance between the leafs and quarter. I do wish it was stainless instead of aluminized, but seeing as my last system (a recycled no-name dual I got free used off of an 81 Trans Am project car) lasted 15 years with no issues, I'm sure I'll be fine.

Based on this experience, I'd reccomend the Flowmaster system over the Magnaflow for those running the thorleys....

Any chance you could post a sound clip of your Borlas? I have the same exact setup as yours except I have Dynomax Ultra Flos. I am thinking of trying a set of Borlas and would like to see if I can get a sense of the difference in sound (either volume or quality).

Thanks,
Marc

I'll see what I can do if it ever stops raining here, but it'll end up being a sound dump on my laptop probably, which isn't likely to pick up low frequencies very well... I'm also still breaking in the re-ring job, so high revs and high load are out for now.

Magnaflow makes the best systems out there period. They have by far the best mufflers and they use the best possible material. The issue is they can't make a system to cover every single aftermarket header. The systems were designed to be universal; it will work with factory exhaust manifolds and headers with some modification. There is even a foot note on Magnaflows website http://www.magnaflow.com/02product/shopexd.asp?zone=American&id=890.
Magnaflow does make center to center, off set to center or anything you would need to build a complete system. The main differance between Magnaflow and Borla is the packing material; Borla uses fiberglass where Magnaflow uses stainless packing material. What this means is you will have a consistant sound over a longer period of time with the Magnaflows where as the Borla keeps getting louder. Don't get me wrong Borla and Magnaflow are the 2 best choices for mufflers. That's my 2 cents.

This Is what I run on almost everything I own, they dont make a direct kit for our cars that I know of, I am still building my 67 so I dont have a clip, these mufflers sound better that any muffler I have heard, ie. magnaflow, flowmaster, great rumble and tone, great sound when you acclerate, and smooths out mellow tone and highway speeds, just my .02.

Henry

I just relised that I did not tell you what kind of exaust I run, well this is what I have and Love.....

http://www.aeroexhaust.com/

Henry

I run the flow master 17104 kit with the 376-y , for the same fitment issues. Tucks up very well with 2.5 pipes and straight out back.

OK, here are a few sound clips I grabbed with my laptop from work. Sound quality could be better (doesn't capture the bass as well as I'd like) but not too bad. I still have a bit of an exhaust leak that I'll clear up when I weld the system up. Also note how quiet the exhaust is while "cruising" along (40-45mph) -- you hear a lot more expansion joints and air than exhaust...

Start & Idle (some revving) from behind the car (I think I had the mic the wrong direction, this doesn't sound the same to me) {2132 kB}
http://putstuff.putfile.com/87264/1732417

Idle, then accel/drive (from pass seat, probably more what folks would be looking for) {1508kB}
http://putstuff.putfile.com/87265/8032563

Generic Drive 1 from pass seat {2128 kB}
http://putstuff.putfile.com/87262/6621301

Generic Drive 2 from pass seat {2213 kB}
http://putstuff.putfile.com/87266/5977821

File hosting care of PutStuff.com
http://www.PutStuff.com/

I love my Magnaflow Stainless mufflers. No obnoxious resonating like chambered mufflers. They are behind Dynatech ceramic headers with ball joint 4 bolt-flange cone reducers. Tail pipes exit like 69 Z28. Wouldn't have it any other way. I'm willing to listen if someone else knows better.

From what I have read, I believe this statement is not quite right. .The main differance between Magnaflow and Borla is the packing material; Borla uses fiberglass where Magnaflow uses stainless packing material.

From each maunfactures web site.

The internal MagnaFlow muffler is designed of stainless steel perforated core, stainless steel wool, and an acoustical absorbent material -- superior to fiberglass (which many other manufacturers use). No baffles, chambers, or louvers. No restrictions at all, just straight-through, wide-open performance with a smooth, deep tone, and each MagnaFlow stainless muffler has a highly polished mirror finish for a show car look.

BORLA mufflers, on the other hand, contain T-304 stainless steel perforated pipe wrapped with several layers of stainless steel sound absorbing material and a blanket of ceramic sound absorbing, high temperature material. The stainless steel inner construction, which is impervious to all corrosive acids, protects the ceramic packing from breaking down and getting blown out, so a BORLA muffler never needs replacing. In addition, a BORLA muffler is the most effective sound-absorbing device for the size, and it is guaranteed for one million miles.

TMessick sorry to hear you dumped the Magnaflow system. I just installed the 2.5" stainless Magnaflow system on my 68 and also had the slightly awkward downward bend issue with mine just off the header but feel I still have plenty of clearance and as for the rest of the fit and clearance of the system its fantastic. Yes the tails dump down and turn in slightly center but I think thats cool ( IMO ). I'm happy with the stainless mandrel bent pipes and the sound is very satisfying to me with an awesome rumble at idle , not to loud going through the gears unless I get on it.

I also preferred to have an X-pipe instead of an H-pipe judging from what I have read on this forum on the performance benefits the X had over the H. But if you are happy with your new system good for you bud , I'm just expressing my opinion on my system.

ANYBODY here, have experience with MAGNAFLOW 15895 Crossflow system (67-69 Camaro)

Please communicate CamarosRus@aol.com

I'm (STILL) in the process of installing the Crossflow 15895 MAGNAFLOW system. Cant believe I'm the only one HERE to ever have done so, but.................

I have system undercar supported by wood and wire.......I dont like cosmetics or security of supplied round rod hangar. I want to come up with SOMETHING ala the 1970 Camaro, whereas there is a hangar directly at outlet of muffler where tailpipe starts, AND from rear frame holding up tailpipe.

I still plan on modifying MAGNAFLOW tailpipe so as it come out back of my 69 Camaro (like OEM) and not turned down like th 67/68

If anybody has GOOD pictures, ideas, PLEASE write...........

CamarosRus@aol.com

Thanks, Chuck