3" xpipe to 2.5" axle-back?

[AaronsSS]

I'm getting a 3" xpipe. But it seems most axle-back/exhausts are 2.5" (borla for ex.). While looking there aren't many options for axle-back w/mufflers that match 3". Is it common to merge these? or are they meant to be merged? can they cut/weld to merge? Cause if this is common, being able to choose from 2.5" axle-backs will provide many more options.

[Mr_Draco]

Question is why are you getting a 3" x-pipe? Are you forced induction and are putting out that much hp that you need the extra flow over the standard size? If not, then there is absolutely no reason to get a 3". You will not see any difference whether performance or sound wise over the standard size and the simplest solution to your problem would be to not get the 3".

Also, the x-pipe on the Camaro goes near the front, right after the cats and is no where near the axle backs. If you get a 3" x-pipe, you will have a section of factory exhaust pipe in between the x-pipe and the axle backs so you will be required to cut in and install two reducers, one for each side. Come to think of it, the 3" x-pipe won't just fit directly onto the factory manifolds either since they are 2.5" so you will be required to install more reducers in front of the x-pipe.

The more I think about it and see how it would fit, the more I'm convinced you are better off scratching the 3" x-pipe and stick with the standard 2.5".

[AaronsSS]

Originally Posted by Mr_Draco

Question is why are you getting a 3" x-pipe? Are you forced induction and are putting out that much hp that you need the extra flow over the standard size? If not, then there is absolutely no reason to get a 3". You will not see any difference whether performance or sound wise over the standard size and the simplest solution to your problem would be to not get the 3".

Also, the x-pipe on the Camaro goes near the front, right after the cats and is no where near the axle backs. If you get a 3" x-pipe, you will have a section of factory exhaust pipe in between the x-pipe and the axle backs so you will be required to cut in and install two reducers, one for each side. Come to think of it, the 3" x-pipe won't just fit directly onto the factory manifolds either since they are 2.5" so you will be required to install more reducers in front of the x-pipe.

The more I think about it and see how it would fit, the more I'm convinced you are better off scratching the 3" x-pipe and stick with the standard 2.5".

I didn't give enough context. I'm planning on getting this: https://www.texas-speed.com/p-3411-t...ess-steel.aspx
So it comes with everything needed to get to axle-back. I figured that was much simpler and cost effective than piecing together 3-4 different exhaust systems and still gives the option to choose axle-back. Even w/o that xpipe, the catted headers are still a 3" merge... wouldn't I still have to merge a 2.5" catback to that? Sounds like I'd have to merge with reducers regardless with tsp headers.

[1JEWLDSSRS]

Here's a bunch of 3 inch axle backs you can do. Or you can just get a set of mufflers. 3" inlet, 3" outlet, offset, add your own tips of choice.

https://www.bing.com/search?q=3+inch...AVST&ptag=1100

[Mr_Draco]

Originally Posted by AaronsSS

I didn't give enough context. I'm planning on getting this: https://www.texas-speed.com/p-3411-t...ess-steel.aspx
So it comes with everything needed to get to axle-back. I figured that was much simpler and cost effective than piecing together 3-4 different exhaust systems and still gives the option to choose axle-back. Even w/o that xpipe, the catted headers are still a 3" merge... wouldn't I still have to merge a 2.5" catback to that? Sounds like I'd have to merge with reducers regardless with tsp headers.

Ok that makes more sense on what you are wanting to do.

Honestly I would wait and see until you have the kit in hand before buying an axle back. The reason is because most kits like that automatically reduce down to 2.5" at the end in order to fit the factory exhaust. So chances are you are worrying about it for no reason.

[larry_g]

Originally Posted by Mr_Draco

Ok that makes more sense on what you are wanting to do.



Honestly I would wait and see until you have the kit in hand before buying an axle back. The reason is because most kits like that automatically reduce down to 2.5" at the end in order to fit the factory exhaust. So chances are you are worrying about it for no reason.

They also make a 3-2.5 reducer that can be welded in. Mine is 3" all the way back to just in front of the stock NPP mufflers because I wanted to keep the look and ability to tone it down a bit.

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[tartagliazl1]

hey larry got any pictures of how you hooked up the 3" to the npp? iv been looking to do the same thing.

[larry_g]

Originally Posted by tartagliazl1

hey larry got any pictures of how you hooked up the 3" to the npp? iv been looking to do the same thing.

This is the best I have, I can take more if you need.

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[AaronsSS]

Originally Posted by Mr_Draco

Ok that makes more sense on what you are wanting to do.

Honestly I would wait and see until you have the kit in hand before buying an axle back. The reason is because most kits like that automatically reduce down to 2.5" at the end in order to fit the factory exhaust. So chances are you are worrying about it for no reason.

Thanks for pointing that out, this was correct. I confirmed with TSP it goes from 3 to 2.5in at the end, it would be nice of them to point that out in the description lol

[Dega Man]

American Racing Headers will have everything you need to go 3 inch x pipe they make an extension pipe that is tapered down to fit the 2.5 inch axle back or they make a 3 inch system including a muffler. Also I have done quite a bit of dyno comparing with 2 inch headers with a 3 inch collector into 2.5 inch pipe verse the same using 3 inch pipe back to the axle back 2.5 muffler and there are definitely some peak horsepower gain difference 8 hp to 12 hp increase, so if you go that route you will gain a little and have yourself future proofed to future upgrades.