STATELINE

looking to put a 4" system on my 01, any recommendations? looked at some magnaflow systems, but it says the downpipe is 3.5"?? do all the 4" systems use a 3.5" downpipe? or do some have 4" all the way from turbo back? I had a magnaflow muffler on my 05 & loved the sound, louder than stock, but not straight pipe loud. that's what I want for this truck. any help appreciated

97 D-Tec

im pretty sure places like Silverline,bully dog,MBRP make 4" all the way back which is what you want unless of course you want to go 5inch then those kits will have a 4inch down pipe going into a 4-5 expansion pipe and then it will be 5inch from there all the way back

high bid

Yep, just installed a 5" system w/4" downpipe. I think it's an Expandit system...sounds great and it definately breathes better and seems to overall, run better. ebay $326.

97 D-Tec

thats the same one i bought

Silver R/T

who sells that system on ebay?

Dave2001

I put an AFE stainless steel 4" exhaust on mine. Most of the systems I've seen go to 4" right past the turbo flange. I noticed that the turbo would start to spool up quicker, also EGTs went down some. My system has a muffler, it's louder than stock but not like a straight pipe.

high bid

Purchased from "markoidaho." I had an ebay coupon so it made it even a better price but I think they're normally $365. Still a good deal for a complete 5" system. No tailpipe, but I didnt want one anyhow as I painted the entire system w/black bbcue high temp paint. And how much larger does the tpipe really need to be....before you know it they'll have 8 or 10" tpipes.

Big Deezul

The stock turbo has a much smaller outlet then 4 inches so at that point does the down pipe really matter?

97 D-Tec

actually it really does matter ... the faster you can get it to 4inch (getting rid of that stupid stock exhaust elbow) the better. Egts come down, spool up can also be improved as theres less of a traffic jam. as it is with all things related to performance its all about the abiltity to flow

ohanahorse

I got a "cat back" off a 2004 (he went to 5") off Craigs list for 50.00 and it's in great shape....I'm a stock truck, so I'm not replacing the turbo downpipe piece as wrecking yard cut them rather than unbolt