Stock straight pipe vs 4" straight pipe

[firsttofight11b]

What is the advantage to having a 4" straight pipe compared to a stock w/ deletes. Is it just sound?

[lhsnbsaoa]

an aftermarket kit will be a larger diamater (at least 4") which is significantly larger than the stock pipes (usually 3"-3.5"). also the bends in an aftermarket kit are a little more free flowing than stock exhaust. if you want performance upgrades, an aftermarket kit would be better because the exhaust gases would be more free flowing. you would still have sound with the deletes, but you would have more sound with the aftermarket kit.

i had a 4" dual straight pipe kit on my 2000 f350 7.3 and it sounded BEAUTIFUL with very little cab noise. FYI, i bought the kit on ebay for $399 and it worked great. cant remember what brand though

[k.thed]

It seems like my 4" kit with cat delete is much quieter than my buddy's who kept all this stock pipe and cut out his muffler and cat, then welded in pipes that were expanded on the ends. (Both on 6.0L's I might add.) Mine doesn't have the pop and cackle that his does. It sounds much more refined.

[lhsnbsaoa]

4" MBRP PLM EXHAUST SERIES 03-07 F-250/350 POWERSTROKE - eBay (item 300456418588 end time Mar-14-11 08:50:53 PDT)

[firsttofight11b]

That is the exhaust I have been looking at, but you can get it at performancetruckproducts.com for about $230 with discount code and free shipping