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Discussion Starter #1
Just installed a used set of Solo’s I bought from a guy in SC. Install was a breeze, total working time was maybe around 30min. Didn’t use a jack, ramps, or a lift. Easy enough to do on the ground with basic hand tools.

Before I purchased these I did a lot of research into how they sounded. Decided I liked the Solo Axle Backs over any other brand so I grabbed a set.

Overall satisfied with the sound, might need to adjust the J pipes over time, but for now I’m noticing little to no drone and minimal vibration in the cabin.

The only complaint I have is I’m now getting a bang or I guess I’d say a pop, when accelerating from 49mph to 50mph. Literally only at that single mph increase do I hear it. It almost feels as if I’m getting pressure against the accelerator pedal as I’m driving it.

Any thoughts on this? I’m thinking maybe back pressure in the J pipes, or could be something that was always there, but now is just more noticeable. I plan to put in an X pipe in place of the mid muffler later on. Leaving the resonators in however.

Thanks Team!

P.S. Also noticed my GT won’t let me rev past 4K rpm’s when in neutral. Is this normal? Thanks


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Nice pick on the Solo. It has been our most popular system for the G8 by far. IS the popping come at light throttle or is this on hard acceleration? Does the car have any other mods?
 

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Discussion Starter #3
It seems to be under light acceleration, I’ll be driving it more today, so I can do some more testing. The Axle Backs are the only mod I’ve done so far.


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I have the Solo Catback Mach Balanced, still on OEM tune and no popping sound. I am guessing, is an Axelback, so you still have the OEM Resonators and Muffler? I am sure but I think there is no T or X crosstube either.
 

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Discussion Starter #5
Yes I still have the mid muffler and stock resonators. I was reading that Solo designed this system for a 2008 model, and that in late 2009 the exhaust design was changed in some way and could possibly cause changes in the way Solo’s product performs.

Not sure if that’s true, or if it is, to what extent the changes would affect their products.


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Car has rev-limiter in neutral and is completely natural.

For the late 2009 exhaust change, they added an extra set of pup-cats and reduced the mid-muffler to a smaller size, it will be very easy to tell which you have by looking for an extra set of cats or by vin (last 6 digits start with 3). The factory mid muffler for the 08-09.1 cars have a balancing section in the middle of the muffler also which was not done on the 09.5 muffler.

My experience with solo axle-back and a 09.5 mid section: i had to extend the J's to as long as they could go to get the low rpm's to a tolerable level. This was the only way to get the little drone it had from 1200-1400 rpms down.

In regards to the popping you are having, this axle-back will pop on decel, but i have not heard of them popping when accelerating. How are you testing the popping between 49-50? Are you repeatedly decelerating and accelerating around 49-50 making the rpms go up and down? This fluctuation will cause the exhaust to pop similar to how it does on decel.
 

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I'm guessing you're getting the pop after being off the throttle, then getting back on it. Transition point. Mine does the same thing, and it's more pronounced at certain speeds. I believe it's caused by DFCO (deceleration fuel cut off).

Also, as mentioned. 2008 and 2009 have the same exhaust. 2009.5 is the different one.
 

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Discussion Starter #8
Ok so I don’t have a 09.5, just checked my VIN. So that gets rid of one possible issue I suppose. Did a little cruising this morning and the popping (which happened when accelerating past 49mph) seems to be leveling out. Yesterday the first 30 minutes of driving it was very pronounced.

Glad to learn about the rev limiter in neutral as well. Thank you.

At lower RPMs there is some heavy resonance, or vibration at the back end of the vehicle. It’s not quite a drone. I think in part it’s normal, and my ears just aren’t used to it quite yet. The Solo’s don’t have tips on them yet, the seller used them on his new setup, so they are about 8-10 inches short.

Could that fact cause more of a vibration, or a resonance?

Thanks again Team
 

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Given that the instructions for the J-pipes say to move them in 0.5 to 1 inch increments... I'm gonna go ahead and say yes, having the tips missing could certainly make a difference.
 

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Discussion Starter #10
Well having had the Solo’s for about a month now, I’ve come to the reluctant verdict that this isn’t quite the sound I’m looking for.

Just posted in the WTB section, but I think now I’m going to do a full cat back swap rather than just the Axle Backs. Looking for a Corsa system to be specific.


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Just put a Corsa system on my GXP, removed the Solo axle backs. Little bit milder but pops are still there. Corsa will be expensive. You might want to try a Solo cat back with a couple resonators. Is your AFM off?
 

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Discussion Starter #13
Just put a Corsa system on my GXP, removed the Solo axle backs. Little bit milder but pops are still there. Corsa will be expensive. You might want to try a Solo cat back with a couple resonators. Is your AFM off?


No it’s not tuned out, and I haven’t tried turning it off in engineer mode. If I can find a deal on a Corsa set-up I’d be looking into doing more work as well, I.e. Tune, DoD delete, otrcai etc.


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Not bashing the Corsa in anyway, it's clearly a great exhaust, but a ~$200 Cortex to give you a bit more power, trans tune, and turn off DOD might be worth looking into before shelling out the cash for Corsa.
 

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Not bashing the Corsa in anyway, it's clearly a great exhaust, but a ~$200 Cortex to give you a bit more power, trans tune, and turn off DOD might be worth looking into before shelling out the cash for Corsa.

A Cortex does all of that? Meaning tuning the TCM and tuning out DOD?


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A Cortex does all of that? Meaning tuning the TCM and tuning out DOD?


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Yep.

Engine: There are "factory tunes" for 87, 91, and 93, or in my case I paid the $2.99 for the Roto-Fab specific tunes. There are tunes for VCM, Vararam, etc
Trans: You can change a number of things. I load the canned tune with most options set to stock, then use the +25% shift firmness. Beyond that is a bit much for just driving around. Honestly, the trans tune is the best part. Really changes the way the car drives.
DOD: Yep, turn it off.
 

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Discussion Starter #17
Yep.



Engine: There are "factory tunes" for 87, 91, and 93, or in my case I paid the $2.99 for the Roto-Fab specific tunes. There are tunes for VCM, Vararam, etc

Trans: You can change a number of things. I load the canned tune with most options set to stock, then use the +25% shift firmness. Beyond that is a bit much for just driving around. Honestly, the trans tune is the best part. Really changes the way the car drives.

DOD: Yep, turn it off.


That’s something I’ve never even thought of using before, that’s pretty cool. I’ve got a buddy with a Focus ST who has a Cobb tuner that’s similar to this. I had no clue something like it was available for the G8.

I was thinking of doing a tune through Livernois or PCM of NC whenever I did things like an intake or headers and what not. Does the cortex support mods like headers? Or is it geared more towards simpler bolt-ons?


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That’s something I’ve never even thought of using before, that’s pretty cool. I’ve got a buddy with a Focus ST who has a Cobb tuner that’s similar to this. I had no clue something like it was available for the G8.

I was thinking of doing a tune through Livernois or PCM of NC whenever I did things like an intake or headers and what not. Does the cortex support mods like headers? Or is it geared more towards simpler bolt-ons?
The Cobb Accessports do A LOT more than a Cortex. I wish we had something like that, but then again, for the price of one of those, you can get a custom dyno/street tune.

Cortex is mostly simple stuff. Headers will be more than it can do. There are a few videos on youtube about the cortex on the G8.
 

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I have j pipes with x pipe and I have like a delayed burst of fart at 2K rpm. I think its the sound of the pressure bouncing off the end caps and re circulation back through the J and out the tips.

So, I NEVER adjusted mine. What does pulling them towards rear end do vs towards front of car?

I mean any louder one way or other? Or just change in tone? I have LTH, HFCs and nothing else in between except the x.
 

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I have j pipes with x pipe and I have like a delayed burst of fart at 2K rpm. I think its the sound of the pressure bouncing off the end caps and re circulation back through the J and out the tips.

So, I NEVER adjusted mine. What does pulling them towards rear end do vs towards front of car?

I mean any louder one way or other? Or just change in tone? I have LTH, HFCs and nothing else in between except the x.
Adjusting the j pipes to get rid of drone, if you don't have any then no need to.

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