This is just for everyone interested that enjoys the planning stages and is curious for ideas about true duals. I have revised this thread 3/15/13 starting at this first post. So far via search this is what I've come up with for ideas. This will be mounted to existing Hooker Long Tubes and I have BMR boxed SFC's. Offer up suggestions or criticism of any kind if you like:

- Summit or Jegs Universal X-pipe assembly (which is better)?????????
- Autozone exhaust hanger(s)
- Use stainless steel band clamps from Summit or Jegs
- Miscellaneous 2.5" Mandrel J and U bends (aluminized) - Walker/Dynomax
- Use aluminum tape with the band clamps to prevent leaks (welding optional for later)

- So far the muffler choices could be any of these three:

- Magnaflow 4 x 9 (muscle car like, well liked, quiet until you step on it)
- Magnaflow True X Muffler (X-pipe within muffler, nice fit in stock location)
- Borla Pro XS (I'm leaning toward this one or even the Borla "Turbo" which is the same thing but a little longer and quieter. These mufflers are highly rated and test with the best of them...quiet all around but nice tone and polished stainless, very high flow)

I may go over the axle on the passenger side with both 2.5" pipes to ease the installation (inline fuel pump and other things in the way on the driver side). I may use the Magnaflow True X in the stock location or two smaller mufflers there. Or I may use one muffler in the stock location and another in the spare tire/jack space after hammering it out of the way. I will likely use a 90* mandrel bend on the driver-side of the X-pipe at the end and relocate the 45* leg (included with the X-pipe) onto the end of the 90* bend so it can run parallel with the passenger leg of the X-pipe. This could ease the start of going over the axle on the passenger side.

I am also considering going under the axle just to make things much simpler. 3-bolt flanges after the X-pipe would connect to pipes under the axle and they'd go straight back to mufflers and tips kind of like a conventional dual exhaust (instead of bending all over the place). I feel like over the axle is best but under the axle would be much easier for me to do (don't have a pipe bender) and probably acceptable since this isn't my daily driver and my wheel/tire height is 26.2" (slightly more clearance under the 12-bolt). The 3-bolt flange would allow the rear exhaust assembly to be removed for suspension / rear-end service.

I would only have the system welded after I have made all adjustments as I find what needs to be done as I drive it. I may never bother with welding if the band clamps and Copper Gasket spray / fiberglass cloth (or aluminum tape) keep leaks at bay.

Any suggestions / criticism is welcome, thank you.

 

sorry, i am not a lot of help on true dual design or muffler sound options but unless you are really good with a sawzall, i suggest a good hacksaw with buck bros blades as you will get much squarer cuts.

Also forming your own bends is going to require quite a bit of tooling (probably want mendrel formed bends, e.g.), don't have any personal experience with these guys, http://www.coneeng.com/index.html, but seem to have a very thorough and well thought out inventory for do-it-yourself exhaust.

Lastly, search the exhaust forum for true duals as I recall a couple threads with a lot of pictures.

 

Just learned something new from a very informative link, first I'll paste what I learned (about aluminum tape) and then the link:

"What clamps should I use?
Invest in some good band clamps; they can be found from message board sponsors and auto parts stores. U-bolt clamps are junk! Another option is to use flanges. If you're using clamps and still have exhaust leaks, try some aluminum tape from Lowe's or Home Depot. Wrap the tape around the collector (at the header or Y-pipe) for a thicker area for the clamp to seal up to."

....maybe I won't need to weld anything after all.... here's the link, even though it's called "LS1 Sounds" there is a lot of good info and some LT1 vids there too:

http://www.ls1sounds.com/

.

 

I've been telling everyone to use band clamps for years now. They might not always seal 100% the first time but always being able to adjust things or take them apart should you need to is well worth it.

 

No doubt. Do you think they can seal 100% if enough aluminum tape (or other) is used? I know there are other products like JB Weld and what not that may also be useful, not sure though.

 

The thing I'm really struggling with the most at this point is muffler choice. I think I have it narrowed down to the following:

- Borla XS (videos of them all sound very different, can't pick up a consistent tone; tests show them to flow very well and also be relatively quiet, they're stainless and a bit bigger/heavier and expensive ....too quiet? ...weird souding?... not sure yet.

- Magnaflow 4x9 (great compromise that's similar to the Borla XS but louder at WOT ...videos confirm it has a decent sound, users seem to be very happy.

- Magnaflow Tru-X (fits in stock location nicely, one member in here used it and likes it a lot, video confirms a pretty nice sound IMO, I would say this flows really well and may even bump up torque due to the X ....lots of obvious advantages to this but for some reason I'm weary of it????

Thoughts or vids with any of these mufflers are appreciated, thanks.

 

I can't seem to find any answers or get any consistency about band clamps. People say they're great, other people say they leak. People say to look into getting them with the nuts built in ...I can't seem to find anything like that for sure. Do these have nuts built in? :

http://www.summitracing.com/parts/SUM-692250

http://www.summitracing.com/parts/SUM-693250

I do understand the difference between butt joint and lap joint. People say to use exhaust tape with them. Others say no ....use high temp RTV. Then people say use loctite ....arghhh. To me aluminum tape seems to be the best option? ...or exh tape? ...what's the difference? ...is there a difference? lol this TRUE DUAL PLANNING stuff's driving me nuts .....TOO MANY VARIABLES!

It seems the best method is to use as many slip-fit lap-joints as possible if you want a weld-free yet leak-free exhaust. The tape and high temp RTV may help with this.

 

In response to your last question about the band clamps- I just put them on as the pipe sat. With my exhaust set-up you can't hear any leaks, but its so loud you wouldn't hear them if there was anyway. I would assume if you used some aluminum tape on the joint then put the band clamp over it would help seal- but I wouldn't do much more than 2 layers or so- they fit pretty tight as it is.

The ones you linked to are probably good clamps, and don't appear as though they have the nuts built-in. I don't see much benefit either way except with built-in nuts its one less wrench you will need, but it will put all the stress on the clamp itself when you are tightening it up, but probably won't be an issue.

As far as your tips- I suppose you could oval the 2.5" pipe and cut back the 2.25" section of the tip to where it widens out so you won't have to run a reducer first, if that makes sense.

 

Walker/Dynomax has huge inventory of mandrel bent pipes available at Summit. Seems that the best idea is to use several U bends and cut them up to the angles/lengths you need.

My muffler choice is still down to these three:

-Borla Pro XS (or slightly larger "turbo")
-Magnaflow 4x9
-Magnaflow Tru X

I will be using some nice stainless SLP dual/dual tips I bought off of a member in here since they fit the bumper profile and smooth out the exhaust note some.

 

Well, this project got putt off in lieu of other things more important so I'm bringing this back from the dead and I've revised it from the first post. I'm back on to at least buying more parts. I already have the SLP stainless dual/dual tips and I'm about to order an X-pipe because I could use the U-bolt clamps included with it to space my sway bar down to clear my 12-bolt (I'll be using band clamps exclusively for the exhaust system).

Anyone have an opinion on Jegs vs Summit X-pipe assembly?

Also still not 100% decided on the three to four different muffler choices but I'm thinking the biggest / quietest I can fit is ideal, so probably Borla "Turbo" muffler or slightly smaller Pro-XS.

 

I was reading what you were saying about sealing up the band clamps and I think I can offer a better idea than the aluminum tape. Take a look at felpro pt# 2499. Its a 12" by 28" sheet of exhaust paper for making exhaust gaskets. When I put on my magnaflow catback, I had a problem sealing up the front connection with the lap joint clamp, because magnaflow had reduced the size of the pipe to slip into the one in front. I cut a strip of the 2499 paper and wraped it around the pipe and then clamped it. Havent had any leaks yet and its been a year.

Just thought it would be another option to look at instead of the tape.

Let us know how it all turns out!


As far as the mufflers go, I always leaned toward flowmasters, until I heard the mangaflow and I fell in love with the sound. Not too loud for crusing, but nice and throaty when you get on it. One thing Ive noticed with my magnaflow, is that at first it will be pretty quiet. Then as the fiberglass packing in the mufflers goes through a couple of heat cycles and "breaks in", it will get louder, but not to loud.

Hope this helps!

 

Thanks for the input on the felpro pt# 2499, sounds like a good option! Hey folks, interested in making an over the axle setup easier? ...check this upper panhard bar relocation kit out, very good price at $90.00 (less than half as much as BMR's version):

Panhard Rod Relocation Kit - Founders Performance LLC

I think I'll use that and go over the axle even though it's more trouble ....argghh.

Well for those reading this, I am getting ready to buy an X-pipe and will either go with Jegs or Summit. Can anyone recommend one over the other or are they pretty much exactly the same (if anyone knows)?