RubiCAT Gettin EVO'd UP!!

MTG said:
I believe its because they need to keep both sides of the exhaust equal length in the 2012.

Exactly right. By keeping both sides equal length, Chrysler has created a scavenging effect due to exhaust pulses. When an exhaust pulse reaches the y pipe, due to the firing order there are no other pulses there to cause interference. The pulse travels by the other leg and the velocity of the flow passing over the other leg causes a vacuum in that leg, in effect pulling the other exhaust pulse (from a later "firing" of a different cylinder) out of the other pipe. Just like an X pipe in performance cars like the corvette.

Improves torque and horsepower :)

Reason I know this is that I work on the exhaust system development of a "future" vehicle running the pentastar and a very similar equal length ypipe.
 
The JK bugle removed from RubiCAT...
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Off Road Evolution was able to save the bugle and make it work with their long arm kit by flipping it around.
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You can see that it will clear the EVO Long arm at full stock bump.
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ok, so it is modified... well sort of.
 
what MTG said, impostr knows his stuff. you really want to keep the lengths of the pipes equal from the headers to the y-pipe to help maintain optimal performance.
 
Oh, almost forgot to post this up. After reinstalling our exhaust, we decided to leave just the resonator in and keep the muffler off - I wonder how it will sound?

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in spite of what some may try to suggest, i don't like tom wood shafts because he chooses to use cheap u-joints that are made in china and i have seen them fail prematurely and for no good reason time and time again. granted, this is just what i have seen and so you can take that with a grain of salt. of course, you can pay to have them upgraded with a set of spicer or neapco u-joints but, that makes them more expensive. regarding coast, i have run them in the past and they are really good drive shaft that come from the factory with spicer u-joints. i would recommend them to anyone. as far as why we decided to go with je reel, they are local to us and build their shafts using high quality made in the usa neapco u-joints. i have run their shafts in the past, have good experiences with them and would highly recommend them as well.

Thanks, for the info! As I suspected, you had a good and logical reason for choosing what you did. Looks like a set of JE Reels will be going on my JKU.
Thanks again,
Bill
 
For those of you who are intersted, we just got done reinstalling our exhaust system on our 2012 Jeep JK Wrangler and, just to hear what it would sound like, we purposefully left off the factory muffler. Please note that the 2012's do come with a resonator and that has been left in place.

 
Pretty smooth sound. That ypipe gets rid of most half order noise (which is the source of the throaty "v8" tone).

This motor reminds me a lot of Nissans 3.5l it 3.7l motors in the 350Z/370Z (they have similar equal length pipes, but since packaging is better, they dont have a bugle pipe). Smooth, powerful sound.
 
Yeah I have seen ALL the videos...Are you Running 5.38's? I did test drive one a couple years ago at a local dealership that was lifted with 37's i think and it seemed to have plenty of power. This coming from the guy that was running 33's with 3.05 gears...lol...Not any more, but I didn't think it was as bad as others in the area had said. Maybe the got a lemon. The local "4x4" shop owner had an 07 with 35's, super charged, 5.38 gears and he said it was his worst investment. I try not to let people like that sway my decisions. Would you recommend an Automatic or 6spd.?

in the recent videos, we are running 5.38's in our dynatrac pro rock 60's. in a dana 44, i personally wouldn't run anything higher than a 5.13 as the pinion on a 5.38 gets to be really really small. as far as superchargers go, everyone i know who went that route has experienced nothing but problems and i wouldn't recommend it for how little you get out of one.

regarding transmissions, i love manuals and have wheeled them my whole life but, wheeling an auto is so much easier. i would recommend that you go that route.



skip the long arms, get only the suspension components you absolutely need and skip all the other extras like bumpers, etc.





what robar said :yup:

I would 100% agree with Eddie regarding superchargers, 94YJBeaver I went with the RIPP Stg 2 it does add noticeable power but as Eddie might remember I had quite a bit of trouble in Colorado last year with the RIPP. If power is a real issue, I would suggest and I am currently saving my pennies (Loonies I’m Canadian. lol) for a Hemi conversion.
PS I have 513 in myt Dana 44 but I have order 538 with my Dyantrac Pro Rock 60.
Good luck.
 
For those of you who are intersted, we just got done reinstalling our exhaust system on our 2012 Jeep JK Wrangler and, just to hear what it would sound like, we purposefully left off the factory muffler. Please note that the 2012's do come with a resonator and that has been left in place.


well, what are you going to run?
 
Thanks for the heads up...All this info is very helpful...


I would 100% agree with Eddie regarding superchargers, 94YJBeaver I went with the RIPP Stg 2 it does add noticeable power but as Eddie might remember I had quite a bit of trouble in Colorado last year with the RIPP. If power is a real issue, I would suggest and I am currently saving my pennies (Loonies I’m Canadian. lol) for a Hemi conversion.
PS I have 513 in myt Dana 44 but I have order 538 with my Dyantrac Pro Rock 60.
Good luck.
 
Sounds Ferrari ish at high rev. Might have to do that to mine for a bit until I get my muffler just so I can hear the engine to shift, These 2012's are so quiet...
 
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