Difference in Downpipe Brands

[sunwolf]

I'm looking at getting down pipes at some point soon and I was wondering if there are any real differences in 2.5" downpipe from any vendor. Let's keep it from getting heated here but I can't see how they can be all that much different. LME says their downpipe will throw a CEL on stock tune so I can't roll into the dealer with their pipes but others say they have no problem. Has anyone owned or used multiple sets? Is there any real difference between manufacturers? Wanted to go with catted downpipe by the way.

[J-Will]

LME and PPE are 2.5".  LME says theirs might throw a code, basically CYA in case it does.  Both have potential to do so, though PPE has yet to.  LME updated their cats and shouldnt either. 

PPE offers ceramic coating options for aesthetic upgrades (and while proven otherwise, I think better heat dissipation if even only realized in the long term). 

Unleashed has 3"

My personal thought process (I do not have DPs or Tune... or anything modded yet for that fact; I'm wrestling with the same questions you are, and more with other products):
*2.5 or 3? 
If 3, then there is only one option

If 2.5,
*Do you want coating yes/no?
If Yes, PPE
If No -

*Are you going to, or do you have a tune with LME?
If Yes- I'd support the tuner, and continue being their customer for prolonged support
If No - Go with the cheapest option

[J-Will]

I dont think I emphasized your CEL enough in my thought process.  The final decision is your confidence in the CEL versus swapping out the pipes versus getting a tune eventually.  I think that one is all up to you. 

[sunwolf]

LME and PPE are 2.5".  LME says theirs might throw a code, basically CYA in case it does.  Both have potential to do so, though PPE has yet to.  LME updated their cats and shouldnt either. 

PPE offers ceramic coating options for aesthetic upgrades (and while proven otherwise, I think better heat dissipation if even only realized in the long term). 

Unleashed has 3"

My personal thought process (I do not have DPs or Tune... or anything modded yet for that fact; I'm wrestling with the same questions you are, and more with other products):
*2.5 or 3? 
If 3, then there is only one option

If 2.5,
*Do you want coating yes/no?
If Yes, PPE
If No -

*Are you going to, or do you have a tune with LME?
If Yes- I'd support the tuner, and continue being their customer for prolonged support
If No - Go with the cheapest option

I am tuned by LME and I do want to go with their product but I am also still under warranty and do not want to take the pipes off every time I go to the dealer. LME is cheaper for me also since I live 35 miles away and I can go pick them up (don't think I should waste my money on install if its 12 bolts and I can use my friends lift).

[jayskycj]

I am running PPE catted dps with an Livernoise tune. I pass NC emissions with no code. Not downing Livernoise at all, just FYI. I also discovered my 3bar tune blocks the o2's so I had to return to stock tune before my emissions test. No big deal.

[AJP turbo]

I am running PPE catted dps with an Livernoise tune. I pass NC emissions with no code. Not downing Livernoise at all, just FYI. I also discovered my 3bar tune blocks the o2's so I had to return to stock tune before my emissions test. No big deal.

If you pass emissions with a tune then why do you have to return to stock?....they don't block the rear 02's they just shut them off so you don't get codes but in doing so you will never ready the I/m monitors

[AJP turbo]

The fact that you are passing emissions has nothing to do with your tune but more because the cats are efficient enough to satisfy the parameters in the stock tune and the unaltered obd settings in the 3 bar tune.none of the commercial tuning companies are adjusting the the items nessasary to to facilitate aftermarket cats or lack of  to pass emissions as it's highly illegal...they've said so on this vary forum.

[EcoPowerParts]

The cats used on the PPE pipes are very expensive and very high quality, these cats not only flow better than stock or other aftermarket cats but also work correctly for your vehicle and ECU.
On my wife's truck I ran it 6 months on the downpipes (same 2.5" cats) on stock tune, no CEL. On my Flex I ran catted pipes and made 600WHP with the cutout open post downpipes. They can flow as much power as you can possibly make and still will not throw a CEL. As far as 3" vs 2.5" the 2.5" pipes can support around 400WHP per pipe (800WHP) so until we start getting to that scenario the 2.5" is more than enough for anything you guys can make.

The only way the PPE pipes are competitive with others is I'm selling them at a very very low margin as I have very little overhead. This helps me and you both, I don't have employees to pay, rent to pay, machines to pay etc. I'm not marking them up to pass on the price of doing business to you. This was my goal from day one, a great downpipes made by an amazing manufacturer that would pass emissions, make big power and be cost effective.

[jayskycj]

I am running PPE catted dps with an Livernoise tune. I pass NC emissions with no code. Not downing Livernoise at all, just FYI. I also discovered my 3bar tune blocks the o2's so I had to return to stock tune before my emissions test. No big deal.

If you pass emissions with a tune then why do you have to return to stock?....they don't block the rear 02's they just shut them off so you don't get codes but in doing so you will never ready the I/m monitors

You answered your question. You can't pass emissions if you don't show ready. So I had to return to stock for the sensors to be ready.

[AJP turbo]

I am running PPE catted dps with an Livernoise tune. I pass NC emissions with no code. Not downing Livernoise at all, just FYI. I also discovered my 3bar tune blocks the o2's so I had to return to stock tune before my emissions test. No big deal.

If you pass emissions with a tune then why do you have to return to stock?....they don't block the rear 02's they just shut them off so you don't get codes but in doing so you will never ready the I/m monitors

You answered your question. You can't pass emissions if you don't show ready. So I had to return to stock for the sensors to be ready.

Read your post jay...you said you pass nc emissions with a lms tune...you contradicted yourself

[jayskycj]

I am running PPE catted dps with an Livernoise tune. I pass NC emissions with no code. Not downing Livernoise at all, just FYI. I also discovered my 3bar tune blocks the o2's so I had to return to stock tune before my emissions test. No big deal.

If you pass emissions with a tune then why do you have to return to stock?....they don't block the rear 02's they just shut them off so you don't get codes but in doing so you will never ready the I/m monitors

You answered your question. You can't pass emissions if you don't show ready. So I had to return to stock for the sensors to be ready.

Read your post jay...you said you pass nc emissions with a lms tune...you contradicted yourself

Sorry for the confusion, I should have clarified I pass with the PPE downpipes and state 4 tune. My bad, so used to running 3 bar. My shows ready stock through stage 4 which in my case is without the tune being programmed for my downpipes.

[AJP turbo]

Still confusing...if you are passing with a stage 4 tune then why are you returning to stock for anything?

[jayskycj]

Still confusing...if you are passing with a stage 4 tune then why are you returning to stock for anything?

I returned to stock to solve my issue of the o2's not being ready. I didn't know they turned them off on my tune. I have a monitor and checked the other tunes I have ( which do not include downpipes, just regular tunes) and they read ready as well. Long story short, my 3 bar tune with dps won't pass ready, but others will. My bad lol, exhausting explanation for my lack of info.

[68_GT]

shouldn't 3in DP's give a tad more power over 2.5 with the rest of the exhaust being stock ?

catted vs catted
&
non catted vs non catted ?

that being said seems like 3in would be the best option. If you want catted buy some high flow cats and have them welded into the 3in (this is what I would like to do).

Or is there a 3in catted option ?

[J-Will]

Unleashed's 3" come catted or not