Thinking about some exhaust system changes.

[Kern Dog]

I've ran 2 1/2" pipes for years. Now I'm thinking of UPsizing to a 3" intermediate section with an X pipe.
The Charger has a 10.07 to 1 493, ported edelbrock RPM heads, a Lunati solid flat tappet 316/326 cam and TTI 2" headers with 3.5" collectors. I added an H pipe last month. I've read tidbits that show the advantages of an X pipe system over an H type. I am going to piece together a system and have the muffler guy bend the 3" pipes and weld it up. Looking for X pipe sections, this was the cheapest one I found:

http://www.summitracing.com/parts/jex-xp6/overview/

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This type seems like a smoother design but I wonder if the extra cost gives better or different results:


http://www.autoanything.com/exhausts-mufflers/69A2672A0A0.aspx

 

[sleepar]

Have the muffler guy make the X pipe as well... I would try reducing the 3" pipe to 2 1/2 for about 6" at the tip in the shape of a 30-06 rifle cartridge if you're into maximizing of gaseous exhaustion.

 

[Kern Dog]

I would try reducing the 3" pipe to 2 1/2 for about 6" at the tip in the shape of a 30-06 rifle cartridge if you're into maximizing of gaseous exhaustion.

???????

 

[Meep-Meep]

Going to a 3" system on your plus size motor might not be a bad idea. I run a TTI 3" with noisemasters on my green Bel (440) and I think it does just fine. No X pipe but it does have the balance tube (H pipe). It seems to do well enough that I don't bother uncorking it at the track.

 

[Supershafts]

Not sure what power you're making, but figuring you're in the 550 area id say 3" merged into a single 3.75

 

[Kern Dog]

I ordered a 3" Magnaflow "Tru-X" pipe kit and a pair of the Dynomax Welded Ultra Flo mufflers. I mocked up the kit. It looks like I'll have to place the X below the end of the Gear Vendors unit to get the best clearance and fit. I doubt it would be a good idea to place the X directly below the Gv since the heat could cook the thin fluid inside.

 

[Supershafts]

There should be room at the extension, in my GT i had it under the extension

 

[Cranky]

Not sure what power you're making, but figuring you're in the 550 area id say 3" merged into a single 3.75

I think that's a good idea. I've had two vehicles with a single large pipe and it seems to work well.

 

[Kern Dog]

there should be room at the extension, in my gt i had it under the extension

GT ? As in Magnum GT ?
I do have room in front of the GV unit. I have to look and see if the pipe sections I have are long enough to go from the X to the mufflers. If not, I'm stuck with placing the X under the front yoke of the driveshaft.

The pipes are stainless steel. I've never welded stainless before. Today I bought a spool of stainless MIG wire. The man said I'd be better off using Helium gas instead of the Argon mix I have now. I'm not getting a helium tank for this one job. he said the welds may not get hot enough but he has seen it done.

 

[cdr]

the welding will be just fine.

 

[Kern Dog]

the welding will be just fine.

You are right about that.
I found that with the SS wire, the gas mix is fine. The welds I did from overhead laid flat. Its the sideways and upside down welds that suck ***. I cant get the same results as i do from overhead. The weld wants to "drip" out. I called a buddy that suggested to increase the wire speed and weld in pulses when doing sideways and upside down stuff. I'll have to try that tomorrow.
The center section was tacked in several spots before removing it to weld out of the car. I'm on jackstands with limited space to work and move so welding away from the car is much easier. I hope to have it done tomorrow.

 

[62 Dart Convertible]

I'm on jackstands with limited space to work and move so welding away from the car is much easier. I hope to have it done tomorrow.

I'm not envying you Greg, on your back tacking up an exhaust sucks - I've known that 1st hand

 

[Supershafts]

Make the welds you need to out from under the car and then make connection points where needed, like weld the X to the 45's and then make flanges to bolt to the header flange, and then to the muffler.

You won't have burns all over your body that way, or you can use band clamps to keep it lighter

 

[Kern Dog]

I finished up today. The pipes start at the header collector 3 bolt flange and end at the mufflers with a slip fit and band clamps. This will make it easier to remove the center section if for transmission removal if needed.
Man Stainless Steel is hard! I took a grinder to knock down some of the welds and I made more noise than I did any progress. It is all welded though, bolted in place and leak free. There aren't even any rattles!
At idle it is quieter but still sounds good. the sharp & raspy tones of the Flowwmasters are gone. It now sounds more like an even growl. At 60-70 mph it is so quiet, the axle whine makes more noise than the engine. The car never had a drone noise with the FM mufflers but it was just louder than I liked. Under power the car sounds great. The Air/Fuel ratio is about the same or richer than before. I expected it to lean out. Power seems about the same but I didn't drive it a whole lot.
Thanks for the suggestions guys, Greg