Issues with AA Midpipe

[Automotive Goals]

Yesterday I installed the AA midpipe with my Stock Competition exhaust. I cut my exhaust as described (1.5 inches from the weld. Actual got the cut perfect, was a bit surprised). When lining up the AA midpipe and the exhaust, the AA midpipe was way too long. I couldn't really cut more into my stock exhaust, because I wouldn't have much room to grab on, once the connection is put on between the stock muffler and the aa midpipe. So I had to cut some of the AA midpipe to make it fit. Pictures attached is the amount I had to cut and the next photo is after the cut, where you see the pipes barely have any distance between them, so the cut was necessary.

After I cut the AA midpipe, everything fit good. The midpipe definetly makes a huge difference in sound. It is louder, more pops and Deeper. Sound is good.

Yesterday I drove and there was no issues. Today when I drove, at low rpms there is a slight drone and it sounds like two pipes are hitting each other (not sure if any pipes are actually hitting, just the best way I can describe the sound I am hearing). This only happens when the exhaust is cold and at low rpms.

Anyone have any suggestions? I figured the AA midpipe would have fit perfectly after I cut my exhaust pipe exactly as was described. Did anyone else have fitment problems? I am just wondering if I got one of the pipes defective. Any input on the drone and pipe sound at low rpms? I did make sure everything was very tight and sitting correct. Even revved the car as it was still on the lift and made sure there was no air leaks or weird noises. While the car was warm, I did not hear any problems.

[dpgfunk]

It's most likely the midpipe hitting the center brace -- check visually. Support the pipe to make sure there's adequate clearance between the brace before you tighten it up. You could also place some washers/spacers for good measure.

[milk242]

When I installed mine, I had all the bolts loose and put a piece of wood (thickness of an iPhone with an Apple case) between the brace and mid pipe and then tightened everything down and then removed the wood. Although things are pretty close to each other, I do not have any rattles that I read about on this forum.

[Automotive Goals]

Originally Posted by dpgfunk

It's most likely the midpipe hitting the center brace -- check visually. Support the pipe to make sure there's adequate clearance between the brace before you tighten it up. You could also place some washers/spacers for good measure.

Im going to take it to my dad's shop tomorrow and check everything out. My dad has been a mechanic for over 45 years (so lots of experience), so the first thing that was his concern was that the pipe will be touching the brace. He even suggested we remove the brace completely, to make sure they do not touch. After we tightened everything up, the brace and pipe were pretty close, but they were not touching. We even shook the pipe and saw that after everything is tightened up, the pipe should not be touching the brace.

Weird that I only hear the noise at low rpms, but nothing at higher rpms. My guess is that if it was the brace, then I would be hearing it at higher rpms as well. My concern is that it was weird that the AA midpipe did not align correct to the stock muffler. I haven't read anything on anyone else having fitments issues. I am just hoping that the pipe is not defective in some way. It is only the driver side pipe that was too long, the passenger side pipe that connects to the muffler, fit perfect.

I will be sure to check the brace first, tomorrow.

[Tommy L Garage]

Been there done that
You should do the following:
1. Use spacers (either 4 washers or a nut) to space out the brace from the body. This will give you enough clearance
2. Also check the pipe around where it turns after the downpipes - you may need to bend the heat shield in that space a bit.
3. Check the rear - it comes really close around the rear-dif area by a suspension component. Shake your exhaust and if it hits then you may need to realign it again

[///M///]

Originally Posted by Ecoce1

Yesterday I installed the AA midpipe with my Stock Competition exhaust. I cut my exhaust as described (1.5 inches from the weld. Actual got the cut perfect, was a bit surprised). When lining up the AA midpipe and the exhaust, the AA midpipe was way too long. I couldn't really cut more into my stock exhaust, because I wouldn't have much room to grab on, once the connection is put on between the stock muffler and the aa midpipe. So I had to cut some of the AA midpipe to make it fit. Pictures attached is the amount I had to cut and the next photo is after the cut, where you see the pipes barely have any distance between them, so the cut was necessary.

After I cut the AA midpipe, everything fit good. The midpipe definetly makes a huge difference in sound. It is louder, more pops and Deeper. Sound is good.

Yesterday I drove and there was no issues. Today when I drove, at low rpms there is a slight drone and it sounds like two pipes are hitting each other (not sure if any pipes are actually hitting, just the best way I can describe the sound I am hearing). This only happens when the exhaust is cold and at low rpms.

Anyone have any suggestions? I figured the AA midpipe would have fit perfectly after I cut my exhaust pipe exactly as was described. Did anyone else have fitment problems? I am just wondering if I got one of the pipes defective. Any input on the drone and pipe sound at low rpms? I did make sure everything was very tight and sitting correct. Even revved the car as it was still on the lift and made sure there was no air leaks or weird noises. While the car was warm, I did not hear any problems.

Quick tip. Did you cut with a reciprocating saw? Next time use this tool. Much easier to make the cut and it is always straight. Cheers.

[Zero_Cool]

I second the spacer/washers for the brace. The shop who installed mine actually had them listed on the install invoice lol. They didn’t report any issues with install. I have my valves open and unplugged so sometimes I hear them rattle. Eventually I’ll get an axle back system but it sounds great the way it is now (Stock DPs, CP, AA mid).

[Automotive Goals]

Originally Posted by Tommy L Garage

Been there done that
You should do the following:
1. Use spacers (either 4 washers or a nut) to space out the brace from the body. This will give you enough clearance
2. Also check the pipe around where it turns after the downpipes - you may need to bend the heat shield in that space a bit.
3. Check the rear - it comes really close around the rear-dif area by a suspension component. Shake your exhaust and if it hits then you may need to realign it again

As others have stated, the spacers Solved the issue. All sounds good now. Definitely a big upgrade from stock. More pops, Louder and Deeper.

Thanks to everyone for the input.

[schnell325]

Odd, as AA has a modified brace to cure such problem. I guess you didn’t get one in your kit.

But glad you sorted it out and like it

[Justin.AutoTalent]

Originally Posted by schnell325

Odd, as AA has a modified brace to cure such problem. I guess you didn’t get one in your kit.

But glad you sorted it out and like it

They don't include it unless purchased with the new "race" exhaust (valved system)

Don't ask me why.

I put a total of 3 washers per side on the brace to provide enough clearance when I had the AA mid pipe

[Everling]

I had the same issue with the midpipe and brace while installing it over my thanksgiving break. Drove me nuts while I drove it around for a week before I had some time again to put some washers in. Did the same and used 3 washers per bolt.

[Alan l.]

Seems like a lot of issues for what it is. 1K for a pipe that has fitment issues that requires tweaking and adding washers for something an exhaust shop could do by cutting out your secondary cats and resonator for under $400. I guess it makes sense for those that don't want to touch the stock exhaust system...

Also how big is the diameter of the AA mid pipe? The stock system is dual 2.5" so isn't the AA pipe actually flow less if its under 5"?

Alan

[MrSmartyPants]

Originally Posted by Alan l.

Seems like a lot of issues for what it is. 1K for a pipe that has fitment issues that requires tweaking and adding washers for something an exhaust shop could do by cutting out your secondary cats and resonator for under $400. I guess it makes sense for those that don't want to touch the stock exhaust system...

Also how big is the diameter of the AA mid pipe? The stock system is dual 2.5" so isn't the AA pipe actually flow less if its under 5"?

Alan

Just comparing area, a 5" diameter pipe has double the area of a pair of 2.5" pipes.

[cwazy1]

Originally Posted by MrSmartyPants

Just comparing area, a 5" diameter pipe has double the area of a pair of 2.5" pipes.

this is true. 3.14r^2

[Automotive Goals]

Originally Posted by Alan l.

Seems like a lot of issues for what it is. 1K for a pipe that has fitment issues that requires tweaking and adding washers for something an exhaust shop could do by cutting out your secondary cats and resonator for under $400. I guess it makes sense for those that don't want to touch the stock exhaust system...

Also how big is the diameter of the AA mid pipe? The stock system is dual 2.5" so isn't the AA pipe actually flow less if its under 5"?

Alan

I think the aa pipe is good for those that do it themselves, like I did. I wouldn't be able to cut my own resonators out and then weld another pipe. So I would have to give it to a shop to do it. I like working on my own cars. On the other hand if people give the car in to a shop to do it, then I guess cutting the secondary cats is the way to go.

I am not sure if the sound is different between cutting the cats out and the aa mid-pipe.

On the other hand, it took me about 1 hour to install the pipe. Including cutting my oem exhaust. A few washers solved the problem I was having with the rattling, so overall, it wasn't a bad install. I definitely like the sound a lot more then was with stock midpipe. Plus I got the pipe on sale on black Friday for $800 brand new. Can't beat that.

[ntg44]

Originally Posted by Ecoce1

Plus I got the pipe on sale on black Friday for $800 brand new. Can't beat that.

I knew I should have shopped around better. Couldn't help but feel like I was getting ripped off for the AA mid at $999 "Black Friday deal" but I jumped on it anyways. Oh well, my own fault I guess. $800 is so much more reasonable than 1 thousand for some straight pipes.

[materialdistractions]

Originally Posted by Ecoce1

I think the aa pipe is good for those that do it themselves, like I did. I wouldn't be able to cut my own resonators out and then weld another pipe. So I would have to give it to a shop to do it. I like working on my own cars. On the other hand if people give the car in to a shop to do it, then I guess cutting the secondary cats is the way to go.

I am not sure if the sound is different between cutting the cats out and the aa mid-pipe.

On the other hand, it took me about 1 hour to install the pipe. Including cutting my oem exhaust. A few washers solved the problem I was having with the rattling, so overall, it wasn't a bad install. I definitely like the sound a lot more then was with stock midpipe. Plus I got the pipe on sale on black Friday for $800 brand new. Can't beat that.

Great deal! If you don't mind, can you PM me the vendor.

[Automotive Goals]

Originally Posted by materialdistractions

Great deal! If you don't mind, can you PM me the vendor.

Got it off of eBay. Got a great deal on it and eBay was offering 15% discount on anything that day. So ended up being $800.

[PSI Power]

Originally Posted by Ecoce1

Got it off of eBay. Got a great deal on it and eBay was offering 15% discount on anything that day. So ended up being $800.

Good find. I also got the $999 Black Friday deal. :

[materialdistractions]

Originally Posted by Ecoce1

Got it off of eBay. Got a great deal on it and eBay was offering 15% discount on anything that day. So ended up being $800.

Thanks for the suggestion. I went the same route except with eBay's recent 10% discount. I didn't get it down to $800, but I got it for less than the Black Friday pricing. The money I saved can then go towards getting it intstalled.

[RTCalifornia]

Originally Posted by cwazy1

this is true. 3.14r^2

+1. Simple calculations. 2 x area of the circle of stock 2.5" pipe yields much more than a 3". The tube would need to be close to 4.5" just to be equivalent. Just a thought...

[JamesGames]

The AA mid pipe isn't 3'' it's a 3.5'' oval. Even though the area of two 2.5'' pipes are larger than the area of a single 3'', there are more frictional losses in two pipes vs one, albeit minor or not. The flow rate would probably be similar between the two styles if I were to guess.. AA mid pipe also deletes the secondary cats.