3" testpipe worked with my stock DP fine.

 

you check the flanges much? mine had exhaust residue streaks everywhere. what did you use for gasket material between the two dissimilar diameter pipes???

 

i used stock gaskets and it didnt seem to leak any, the only leak i ever had is when i bolted on a new DP, but thats because the gasket i used was messed up.

 

The flanges are the same and will mate together (flange on catalytic to flange on 3" (or) no flanges if its a slip on).

2.5" dp
2.5" tp (or) hfc (or) stock cat
3" cat back

For "stock" turbo application. Get your 3" turbo back for turbo upgrade. That's my 2c.

 

2.5 inch for both

i have never tired running a larger size test pipe than stock system . but i dont think it will work as said above.

here is a link to a 2.5 inch test pipe that will replace your cat on your stock exhaust system

 

oh yeah the link

http://www.ultimate-racing.com/Produ...Downpipe.shtml

 

Stock cat has a 2.45" inlet and a 2.33" outlet

 

cool, thank you for the proper measurments Jorge T, I knew it was considerably smaller than the 3" outlet and looked very close to around 2.5", good to know the true sizes

 

For an otherwise stock exhaustk the 2.5 inch is the one to get

For any aftermarket exhaust, the 3 inch is the one to get

Will the 3 inch fit? Technically yes, but it is very prone to leaking due to the flange differences and lack of mating surface. Physically it blts up because the flanges are slotted

http://z1auto.com/prodmore.asp?model...ust&prodid=481

Adam

 

thanks for measurements, Jorge T