[angryBits]

DIY'd my Borla Atak Axle-Back on my ZL1 1LE today.

I bought this one: 11925CFBA

The whole job took me about 2 hours. The instructions were aimed at a Camaro SS which is not a complaint at Borla since "technically" they don't sell the axle-back for the ZL1. So a fair amount of the instructions didn't make sense. Oh well...

Installation was really easy. Cutting my OEM exhaust was a small leap of faith but worth it.

One minor hiccup for me was that one of the pipe openings that fits over the cut oem pipe was bent slightly (blame UPS?) and I had to bend it back with a hammer to get it to fit. It cost me 10 minutes.




My thoughts:

Build Quality of the Borla Exhaust is excellent, better than OEM in my opinion. You can tell a lot of thought and care was put into the design. All welds were tidy and shiny.

Weight. I have not yet weighed my OEM suitcase but I can tell it's a fair amount heavier. I'm going to guess I shaved 20lbs?

Looks. The Carbon Fiber tips with the black anodized aluminum insets are incredible. I love it, its just the look I was going for. Anyone wondering if they should spring for the extra $, the answer is yes.

Sound. Its LOUD. If you think you need to go all the way from the cats or even headers to get loud, nope. I did headers, hi-flo cats, mid-pipes and mufflers on my last ZL1, so I know loud. Just this axle-back "ATAK" is louder! The videos do not do it justice. Once you get on it, its so loud you can't help but look around to make sure people are dropping to the floor due to some kind of battle.

At idle, it's a very nice throaty rumble just like you want for your muscle car.

At mild-mid throttle its ANGRY but the cops probably won't pull you over.

At heavy throttle it's shocking. The cops will probably pull you over.

At WOT, well... I just got dizzy with love. It's good! Exactly what this car needed.

All the above is in track mode.
Stealth mode is quieter but IMO stealth with the ATAK is about the same volume (maybe a little lower) but angrier than track mode with the stock exhaust.

CONS:
Price ? $2k just to have NPP valves is asking a lot but I definitely do not regret my purchase. Worth every penny.

One design flaw, err weakness, err potential weakness? The secondary outlets that are connected to the electronic valves, they are not welded to the muffler, they connect via a clamp. There is nothing but tightness of that clamp keeping that second tailpipe from drooping to the floor. I tightened the clamps down with more torque than my torque wrench could measure, but I think it'd be better if there was some kind of brace.

[Stormtrooper1le]

Good luck If you track your car- I already had 2 tips come off on track. Borla stood up and sent me another exhaust no questions asked however 3 tips are now loose.

If this is a daily or occasional drag strip car you will be fine but for a track enthusiast I dont know if I can recommend it for function.

Sound and looks are killer though!

[angryBits]

Originally Posted by Stormtrooper1le

Good luck If you track your car- I already had 2 tips come off on track. Borla stood up and sent me another exhaust no questions asked however 3 tips are now loose.

If this is a daily or occasional drag strip car you will be fine but for a track enthusiast I dont know if I can recommend it for function.

Sound and looks are killer though!

Are you talking about the drooping second tailpipe? If so then this confirms my theory...

I think I'll need to come up with some fix. I have a welding machine, maybe I could do a quick spot weld just to hold it in place.

Bummer.

[gotswap]

For all the clamped bits, I think they recommend to put a tack weld on them? I really like the look of this one

[24v]

Those tips look nice on there.
What was in the instructions for an SS that didn't make sense for a ZL1?

[dbb143]

Put same thing but NPP delete on mine and absolutely love it (saved $500 for not getting the valves, fyi)

[SJFGTO]

Sounds great and I really love those tips. I think I’d use a weld instead of the clamps on those tail pipes. Cheap insurance and too nice a system to worry about dropping a tail pipe.

[staples87]

Originally Posted by Stormtrooper1le

Good luck If you track your car- I already had 2 tips come off on track. Borla stood up and sent me another exhaust no questions asked however 3 tips are now loose.

If this is a daily or occasional drag strip car you will be fine but for a track enthusiast I dont know if I can recommend it for function.

Sound and looks are killer though!

Not to thread jack. Thanks for the heads up on this. Did you notice it happening due to the nut backing out / failing on the clamp? Maybe Loctite could be used as an extra insurance and to maintain the Borla warranty?

[gotswap]

Curious, at that price point and the full system only being $600 more. Why not do the entire system?

[drfeelgood]

So one thing about the Borla exhaust system with NPP, their NPP valve has a tendency to fail. Plenty of threads on this. Mine failed, I sent them a video clip of the awful sound of a half opened valve, and they replaced it no questions asked for free.

That speaks to the customer service from Borla, but also to the fact that they KNOW this is an issue that they never quite got right.

The fact that that second pipe is held on via clamp (and not welded) is a good thing if you ever have to remove it for a failed valve. Chances are, unfortunately, you will

[jvandy50]

Looks good, sounds good

[angryBits]

Originally Posted by gotswap

Curious, at that price point and the full system only being $600 more. Why not do the entire system?

It's $900 more: 140727CFBA

Maybe you were looking at the non-NPP version?

But even at only $900 difference, it's still a good question.

I decided to get the axle back because I can always add the mid-pipes and all that later if I want. Borla will sell you the parts separately and the cost difference is marginal.

At this point the only advantage would be the weight savings which is actually pretty important to me but I don't think my neighbors can handle any louder.

[angryBits]

Originally Posted by drfeelgood

So one thing about the Borla exhaust system with NPP, their NPP valve has a tendency to fail. Plenty of threads on this. Mine failed, I sent them a video clip of the awful sound of a half opened valve, and they replaced it no questions asked for free.

That speaks to the customer service from Borla, but also to the fact that they KNOW this is an issue that they never quite got right.

The fact that that second pipe is held on via clamp (and not welded) is a good thing if you ever have to remove it for a failed valve. Chances are, unfortunately, you will

Are you referring to the AFM valves mentioned in this thread?

The ZL1 doesn't have AFM, thats an SS thing.

[gotswap]

Originally Posted by angryBits

It's $900 more: 140727CFBA

Maybe you were looking at the non-NPP version?

But even at only $900 difference, it's still a good question.

I decided to get the axle back because I can always add the mid-pipes and all that later if I want. Borla will sell you the parts separately and the cost difference is marginal.

At this point the only advantage would be the weight savings which is actually pretty important to me but I don't think my neighbors can handle any louder.

Is there a big difference in sound between the axle back and the full system?