i cant find it in search....is it true the stock exhaust is 2.5 inch then bottle necks down to2.25 behind the rear axle....if so cant i just cut before the bottle neck and weld in a 2.5 straight pipe and anew muffler and have a full 2.5'" exhaust...this would be realy great for me budget wise...

 

Yes that is correct... if you get under your car you can see where the bottle neck is.

You can just chop it off and have muffler welded on.

 

how come most people dont just do this...that would be realy cheap...

cus the crush bends...is that why...

 

Interesting!!!!!!!!!!
Ideas hmmmmmmmmmm

 

You will need to find a shop that has a mandrel pipe bender.

 

the thing with exhaust is, restriction matters less the futher from the engine you are. for example, a restrictive cat is much worse than a restrictive muffler.

my point is, to have a decent muffler put on, you're at around... $200 for a good shop, i'd spend the money on a nice shorty header or downpipe/cat first.

 

I would buy a muffler first, so it sounds good, then go the header & downpipe/cat route...

 

Read this thread about exhaust flow rates

https://www.cobaltss.net/forums/2-0l-lsj-performance-tech-47/flow-calculation-some-lsj-parts-67539/

 

*Read this thread about exhaust flow rates

https://www.cobaltss.net/forums/showthread.php?t=67539

* wow* realy nice post..very informative..
well im already buying the zzp header/down pipe combo i just wanted to complete my setup and was hoping i can do this instead of buying a whole catback...if this would work wich it sound like it will ..ill just buy some straight 2.5" piping and a magnflow muffler and my freind can weld it in for me..it should only be one weld then right before the old bottleneck..ill settle with a crush bent 2.5" exhaust if its going to run me that much cheaper...so my set up will be

zzp combo
1.75" primary
3" cated downpipe
2.5" bolt on exit
stock exhaust piping to before bottle neck
then custome 2.5" pipe to a magnaflow muffler..

i will be running this for my 60lbrs and 2.7" pulley and ported blower..
the flat rectangular mufflers should sound less ricey(rasp) then the cylendrical ones right?

 

i would go for header and downpipe first so you can fine tune the sounds when you change out your muffler. Sometimes headers and downpipes increase exhaust noise by a great deal. If you change out your muffler before getting a new header and downpipe, you may find out it sound 10x worse afterwards, then you'll be searching for a muffler that gets you that sound you want yet again.

 

Thats my exact setup. You will not be dissapointed.

 

Have you dynoed with this setup. Your also running the 60lbs injectors?

 

I havent dynoed yet. Im running 42's and a 2.9, and I felt a noticable improvement when I put it on. Its going to be an even bigger difference for a 2.7 with 60's.