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Discussion Starter #1 (Edited)
Ok, I am at an impasse right now trying to figure out a balance for power and sound.
I will be installing my SRT8 shorty headers this week with the flow master midpipes w/cats. I am keeping the twin 3" tube setup.
So... Use a 3" twin inlet muffler with twin 3" outlets, the a second (optional) muffler for a resonator before I exit out back. Similar to the gibson srt WK setup, just not exiting middle bumper.

I was wondering if the 44 from flowmaster would be too loud for neighbors and go with the 50 instead. I want the added power but I do not want a commander as loud as a Harley.

Dave
 

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Discussion Starter #2
Update: I am going with a Lawson Industries 3" dual in and out 14x22". I am heading down to the exhaust shop tomorrow to coordinate some mods work to the midpipes. The magnaflow midpipes need to have the mounting flange "clocked" a bit to match up with the SRT8 headers. I have two flanges that meet up in a perfect X pattern...ugh.
Pictures coming and a before/after sound clip to add to the exaust sounds thread if anyone wants to do this setup.
Srt8 headers $150
Magnaflow midpipes $400 with cats
Lawson muffler $45 (got a discount)
Pipe work (unkown yet)
 

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Discussion Starter #3
Well, this weekend was a complete poop for installation. The shop I was going to use just didn't give me a warm and fuzzy when it came to getting the job done. I am a big fan of talking with a shop before I contract them to do any work to get a feel for what I am giving my good money for.
First off, they ask why I am even doing an exhaust for a SUV (why bother? was his second question). Then they proceed to offer the flow master 10 series as the most likely best product for my truck (they assume I must have cut my mullet for a job interview and enjoy having the loudest vehicle on the planet).
SO I play along and ask him what kind of lead time he would need to set up a install... None, just drive in when I need it (how likely will he not be busy the day I need it?)
Since I will be installing new headers (he cannot do it), I ask if he has a tow service he works with to transport to his shop modify the mid pipes for install and complete the system... He told me to drive it with open headers, proceeds to tell me how many open pipe systems he recently installed on mustangs and challengers that should be legal.
Could be legal, but I will not even try that option... I like my neighbors and not rocking the town.

I am buying a new welder to modify the pipes myself next weekend. I figure I suck at welding, but I should be able to tack them in place so I can have one of my weld guys at work clean it up.
I try not to use my employees at work to do my work since it is really frowned upon, but I think this one time may be ok.

Dave
 

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Discussion Starter #4
Went back and edited the title to this thread to make more sense and easier to find once I am done.

I have found only one other thread for doing this, but it was about modding the WK 5.7 for the shorty's. The thread I found is awesome and has good pictures for the header install. I am going to ad to it, and any adjustments, for the XK.
The link:
http://www.jeepsunlimited.com/forums/showthread.php?527426-SRT8-Exhaust-Manifolds-on-a-5-7L

I will try to ease removal of the 5.7 log headers by removing the wheel wells, after comment from original poster that indicated it would make things easier, and post some pics on the difference easier vs harder etc...

Then I will continue the install thread with the 3" mid-pipe from magnaflow all the way back to the tail pipe. I am hoping to have a dual 3" into the 22" muffler and exit with twin 2.5" pipes following the OE exhaust path.
3" twin pipes are too big to go all the way back, but 2.5 might just fit with some creative bending/welding.

Dave
 

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Discussion Starter #5
Part one completed! Removed old logs from the motor. What a pain in the butt, 3 busted bolts. At least on the broken bolts it was just the head and much of them remain. I am going to douse them with go ol' PB blaster overnight.


 

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Thanks for sharing, this is an interesting project. Hope you post a video, I'm dying to hear how it sounds. Good luck with the rest of the build!
 

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Discussion Starter #7
Ok, passenger side on now...

Talk about holy cow!! I had to beat the manifold flat on one of the header pipes to fit against the frame. That took over an hour of super hammer

Picture to come, letting phone recharge.

Right now I have removed the front drive shaft to get room to attempt the drivers side. I am already fearing the steering shaft. I may have to try and modify the mount, but first I need to figure out how to slide the header in first.

Dave
 

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Discussion Starter #8


 

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Discussion Starter #9
Well I have met with faiure with these headers. 6.4L headers will not fit :(

Passenger side can be done, but the driver side must be installed with the motor out of the vehicle and even then you must modify the steering mount by 1" into the fender away from header.

That really sucks!

I have to run out to the dealership now and get some oem studs so this vehicle can make the exhaust pipes tomorrow maybe and drive Monday.

The only SRT8 headers I know tat might work are the 6.1L 2006-2011 style shown in the earlier thread link.
I need to try and buy some of those and try again later. Must get the grocery getting working again!

Dave
 

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Discussion Starter #10
Yup, the new WK have a high flow cast header on th SRT8. I am going to ebay these adtry again next month. I am still going to put on the 3" magnaflow midpipes now to pre stage my system for the headers :)

Dave
 

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Discussion Starter #12
Wasn't the hammering for clearence really. The chief issue was the mounting location of the starter, it was in the way. On the passenger side you cut off the useless flange on the tranny for room. I never bothered to look at that when I switched sides.
So, I will try again with either the new cast SRT8 header or the older shorty that was used in the WK write up in the link.

$155 on ebay for new ones of each :)

Just going to sell the 6.4's on ebay and try to get some cash back.

Dave
 

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Discussion Starter #13
Well, pictures coming later this afternoon for the whole setup. The magnaflow midpipe with cats kit did not fit either, the crossover pipe input was too wide causing the pipes from the cats to not fit the stock location over the tranny crossmember.
End result, $1290 for a custom 3" kit from the headers back. High flow cats, bung harware, reduction collector from three down to the stock header, super 44 muffler dual 3" in single 3" out with dual square tip exit just under bumper.

Could I have made it all work, most likely... Would it have been worth the effort and time, no.
Now the new pipe system will fit the 6.1L SRT8 WK exhaust, that will be for the next 4 day weekend I have off.

Ha! Murphy's Law, as I write this the pipe guy just showed me that two 3" pipes will not fit through the crossmember (without getting some rub). So change to a single in single out muffler. C'Est La vie.

Dave
 

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Discussion Starter #14
So I got a great deal on headers, I now own a set of shorty 6.1 and the 2014 SRT cast headers for $200. This this will continue for install pictures of each header for refrence. I am taking them to a shop I know in Fort Worth that will flow check them so I can decide on the best one based on flow.

Dave
 

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Discussion Starter #16
Well, oddly enough the Wife wanted to 10 series muffler... So, I have air breathing monster now :) pictures and sound byte coming in an hour or so after the tail pipe is finished.

Who would have guessed my Wife being the muscle motor lover?!

Dave
 

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Discussion Starter #17

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Wow

As soon as the guy asked why bother, just drive away.lol

Would love to hear how that joker sounds when it's done. I want to add some sound to mine at some point, but DO NOT want the overwhelming drone on long trips. My expedition had a single 40 series: 7 hours of that, and you can't hear yourself for about 30 minutes.
 

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Discussion Starter #19
I took it for a ride down the local highway and I really didn't notice it at all. at 2000 rpm or less it is not there at all. Granted the Commander has a lot of insulation to begin with, like a mini tank. I also have the MDS tuned out of the PCM via my Diablo tune.
If I squish the pedal though, you know I am there.

Dave
 

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so what exactly do the 6.1L headers do? increased performance/louder?
 
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