2.5" or 3" downpipe?

[04GrandPrixGTP]

I recently sent an email to zzp regarding a question I had about downpipe sizes. I want to get a 3" dp because I wanna go 3" catback later on, but for now I just wanna get new headers and keep the factory exhaust. The last thing I wanna do is buy a 2.5" dp now (in order to connect to the stock catback), then when I upgrade the catback, i'll have to buy a 3" dp.

I asked zzp about the exhaust reducer they sell that goes from 3" to 2.5" and if it would work for me to get a 3" downpipe and reduce it to the stock 2.5" (I don't know if that extra couple inches of the reducer would offset any of the mounting points for the factory catback). So when I upgrade the catback, i'll just take out the reducer. After all, isn't that what the reducer is for? I'm sick of zzp's short and ****ty answers. Here's their reply to my email which I hope someone can explain to me:

"Any downpipe can be converted to 3" bolt in exit anytime"

-Turbo Tim

I asked him about the reducer and he gave me that crap. I'm just confused because hes making it seem like the dp exit can be changed without getting a whole new dp, which doesn't make sense to me.

Thanks for any and all help

[Bio248]

if you get headers you will not need a downpipe, they come with one. all headers minus S&S exit in 3".

if you get only a downpipe, definitely get a 3".

you can step down to a different size directly after the downpipe if youd like. the reducer they have is a step down from a 3" downpipe to the existing catback size (from the resonator back).

[04GrandPrixGTP]

I'm pretty sure I need a downpipe since I'm getting the zzp headers and one of the options it has includes either a shorty or a downpipe with or without cat. I'm getting the same exact setup as 2000GTP: zzp headers with catted downpipe

[Bio248]

the shorty is a downpipe, you just have to weld it on yourself.

the other two are bolt in.

[TDCRacing]

So why do you choose to deal with a company that provides such crappy customer service before the sale is even made?


I sure hope you don't need any technical help when it comes to one of their products.


Good luck.

[blueguy]

So why do you choose to deal with a company that provides such crappy customer service before the sale is even made?


I sure hope you don't need any technical help when it comes to one of their products.


Good luck.

X2. Have fun with Zoomer or Eric...or Turbo-douche for that matter...shoulda got the Pacesetter's and welded them and saved well over $200.

[04GrandPrixGTP]

My question is not about zzp as a company or their customer service. I simply asked if anyone knows how to explain this statement: "any downpipe can be converted to 3" bolt in exit at any time." Why would I be posting on this forum if I could get a straight answer from zzp? A lot of the people on here have gotten zzp products and I would think someone can help me.

Regardless if it's a zzp product or not, I was just asking about sizing of downpipes and what would be best for my situation: I'm looking to just buy headers for the moment to use with my factory exhaust, then I'll uprade to 3" catback later on. Any advice?

p.s. I'm not confident with welding any components in, so I'm looking for a complete bolt on solution.

[TDCRacing]

To clarify that statement.....


You would have to cut then weld a expander onto the end of the downpipe. Which I have NEVER seen.

I have seen weld in reducers though. Such as going from a 3'' down pipe to a 2.5'' bolt in flange. So that it will work with your stock exhaust.

[badbrad]

3" or buy headers. cat back is a waste of money. if u want sound, get mufflers.. everyone here is giving u sound advice.............

[04GrandPrixGTP]

3" or buy headers. cat back is a waste of money. if u want sound, get mufflers.. everyone here is giving u sound advice.............

If i were to get mufflers, what size inlet etc. would they have to be?

[Bio248]

the stock size is 2.25" inlet/outlet.

[04GrandPrixGTP]

This may sound dumb, but does outlet size matter with an aftermarket muffler? Isn't that the size of the tips?

[Bio248]

...correct, but if you want to put the stock tips back on youll need to make sure they are the same size.

[04GrandPrixGTP]

All aftermarket mufflers have to be welded in right?

[TDCRacing]

They don't have to be. But it is best. They can be clamped.