Sidepipe max pipe diameter

[Modena]

I am presently working on my exhaust, currently the headers, and planning to make my own sidepipes. Talking live pipes here, are most people's pipes 4" in diameter (max)?

[Aussie Mike]

Mine are 4.5" diameter for the muffler body and 3.5" diameter for the collector and tip. The cats I use are a 4" diameter body and won't fit inside a 4" pipe.

Cheers

[David Hodgson]

I think the factory Robnell 429's use 5". They are quite large but don't really look out of place.

[renovationinnov]

I have got 4" ffr pipes but I reversed the internal muffles /resonators so as to meet the dbrnoise test & put my cats 4'' just inside the guard with the o2 sensor just before the cats meet all tests
pm me you email address & ill send you all the pics as im having trouble post to the site
rob

[750hp]

I had a 3" perforated inner pipe and a 5" outer on the old blue car. Allowed it to breathe well and with a full inch of packing around the perf pipe gave it a pretty mellow exhaust note (at idle anyway).

[renovationinnov]

http://www.clubcobra.com/forums/pict...653576&thumb=1
heres my cats & o2 senors in 4"

[cycleguy55]

I have 3.5" pipes with a pair of Patriot augers (http://www.summitracing.com/int/part...3843/overview/) in each pipe behind my 460. Noticeable tone at idle, a bit of a bark when hard on it, but mellow out nicely at steady speed.

BTW, Patriot also has 20" & 26" side pipe turnouts in unfinished, black paint, chrome or ceramic coated, with or without louvered inserts.

Patriot inserts are available in 3" & 3.5", if you're looking for 4" (at a much higher price), check out http://www.spiralturbobaffles.com/

[cycleguy55]

One thing I've learned about the augers - if you can push them in by hand they're too loose. Mine were and the rattling drove me crazy so I pulled them out, bent the spirals to be a tighter fit and drive them in with a 24 oz. ball-peen hammer. Nice tight fit, no rattles and they even sound better.