DynoMax 2012-Up JK Evolution Competition Exhaust System Installation Write-Up

tae73

Member
For those that installed this on the 2 door 12+ models, what did you do for the last hanger at the turn down?
 

trailless

Caught the Bug
I have a question.

I'm noticing worse gas mileage since I've installed the exhaust. I would average about 17 mpg city and highway. The first week I averaged 14.5mpg city and highway. Any ideas? I thought I would at the least gain some gas mileage. :thinking:

PS, when I was testing the mileage I drove like I would normally. Not hard on the accelerator.
 

RJEEPO

New member
I have a question.

I'm noticing worse gas mileage since I've installed the exhaust. I would average about 17 mpg city and highway. The first week I averaged 14.5mpg city and highway. Any ideas? I thought I would at the least gain some gas mileage. :thinking:

PS, when I was testing the mileage I drove like I would normally. Not hard on the accelerator.

any updates trailless? I just installed the Borla full system so curious about this and will update so we can compare stats. If I can keep my foot out of it :brows: I stomped it going uphill and my mileage readout dropped immediately lol!
 

trailless

Caught the Bug
So I have mixed feelings. The sound above 2000 rpm is great, even when cruising. Stomp on it and it sounds even better. But anything below 2000rpm and there is a persistent and rather annoying drone. I hardly notice it with the doors on, top up and the radio playing. However, with the doors off, at certain points the drone is almost unbearable. Its embarrassing when I have other passengers...

The exhaust also causes a vibration in the cab. Its not bad and most times I don't even notice it. However, its still there. But for $149 after the rebate, I'm satisfied.

Sent from my SCH-I545 using WAYALIFE mobile app
 

RJEEPO

New member
So I have mixed feelings. The sound above 2000 rpm is great, even when cruising. Stomp on it and it sounds even better. But anything below 2000rpm and there is a persistent and rather annoying drone. I hardly notice it with the doors on, top up and the radio playing. However, with the doors off, at certain points the drone is almost unbearable. Its embarrassing when I have other passengers...

The exhaust also causes a vibration in the cab. Its not bad and most times I don't even notice it. However, its still there. But for $149 after the rebate, I'm satisfied.

Sent from my SCH-I545 using WAYALIFE mobile app

cool, thanks. how about the mpg hit, did it improve?

re: drone, I'm kinda' the lone weirdo I like it when exhausts hit their resonant note. it's physics! heck, when we were "kids" we'd run our cars open headers no mufflers at all. TALK ABOUT FINDING THE RESONANT POINT LIKE THAT. WHAT? CAN'T HEAR YOU. YEAH SOUNDS GREAT! LOL

when the cabin does it because of cracked open windows now that I hate.
 
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trailless

Caught the Bug
Mileage went back up to 16.5mpg. I was averaging 17 stock. Currently im running the exhaust, evo bumper/stinger and skids. I can't say how much the extra weight hurt mpg and how much the exhaust improved mpg, of any.

Sent from my SCH-I545 using WAYALIFE mobile app
 

lmaya

Member
Does anybody know what the length of the actual muffler that comes with this kit is?:thinking:
Thanks

The muffler itself is about 20" in total length (see pic attached.)
dynoRuler.jpg

I would also note that for the install, I did have to mod the evap bracket but instead of grinding it i just used a pair of Tin Snips to cu two slits and then used a hammer to flatten them down (touch up with paint to prevent rust).
Evapmod.jpg
 

Dean454

New member
I just ordered these for my wife's 13 jk and my 13 jk, cannot wait to hear how they sound. Thanks for the how to photos WOL.
 

RamP

Member
Has anyone installed one with an Evap skid plate in place? I have a Poison Spyder skid and really like the exhaust.
 
I just ordered these for my wife's 13 jk and my 13 jk, cannot wait to hear how they sound. Thanks for the how to photos WOL.

Post up sound clips once you get them installed. I know Wayalife posted some but moar is always better. I've got a '13 JKU and will likely be getting this set up once I smash my huge stock muffler another time or two. :thumb:
 

Dean454

New member
Post up sound clips once you get them installed. I know Wayalife posted some but moar is always better. I've got a '13 JKU and will likely be getting this set up once I smash my huge stock muffler another time or two. :thumb:

I will. I will post clips on my wife's manual tranny and my automatic. They are supposed to be here Friday.
 

cozdude

Guy with a Red 2-Door
Has anyone installed one with an Evap skid plate in place? I have a Poison Spyder skid and really like the exhaust.

in the original write up the factory skid is left installed so yes you can leave it in place
 

JKWrang

New member
in the original write up the factory skid is left installed so yes you can leave it in place

I did too. As a matter of fact, i removed the one mounting bolt and out my exhaust hanger UNDER the skid and didnt have to cut/grind anything.
 

RamP

Member
I did too. As a matter of fact, i removed the one mounting bolt and out my exhaust hanger UNDER the skid and didnt have to cut/grind anything.


That's perfect. I was worried about the tab that sticks out too. But it looks like it's a non issue.
Thanks
 
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