Dan Sal

Hey guys, I just bought a 2001 s4 and it is completly stock. I have some mods on order and wanted a mean loud sound from that V6 twin turbo engine. This will be my summer toy so loudness is not an issue. I was thinking V-flow intake, bov/dv splitter, apr stage 1 and front mount intercooler with some coilovers to start with. My mind is blank about how I want the exhaust... I have heard alot of videos on youtube with straight pipes... and it sounds rediculously awesome lol I want opinions on everything... Does straight pipping the exhaust bad for the stock turbos or would it do any harm to the engine? i heard people say its bad and iv heard others say its better because its less restriction...
I would like to keep the stock downpipes for now. I was thinking of a 3" Borla Catback but I think it comes with a resinator witch i dont want. I would love to straight pipe the thing but need some more info before I start doing anything.
Thanks

kbonarek

For a stage 1 tune, a front mount won't do you any good other than create a pressure loss and empty your pockets. You're better off with AWE Tuning sidemounts, which are still overkill. I run RS4 sidemounts and don't have any heatsoak issues running a Stage 3 tune here in Montreal.

AWE Sidemounts

Splitter or blow off valves are useless as you're most likely looking to hear the "whoosh" noise. Long story short, the forge splitters (I have them) are barely audible and you gain nothing performance wise over running the Bosch 710N valves which are a fraction of the price. Also, venting to atmosphere with blow-offs or splitters will cause you intermittent rich conditions, trigger check engine lights and put your car into safe mode...repeatedly. So the 14psi of boost your stg 1 tune was making, has now been dropped to~5 to 7 by your ECU because you've upset it. If you want rebuildable bypass valves, look into the APR R1.

R1 DiverterAPR R1 Diverter Valve

Unless your gonna spend the coin to get an X1 Carbon intake (also offered in fiberglass now), don't waste your time or money on a V-flow or any other open air element filter. The subject has been beaten to death that the stock airbox with a good dry panel filter (ITG) and the Darintake mod is more than sufficient.

ITG Dry Filter

Darintake

As far as the exhaust goes, straight pipes are fine after the cats. Noisy as all hell and the OPP will love the fact that you're supporting their friendly business. You'll get to meet a lot of poilce officers. Hope you like flashing red and blue lights. I know, I'm running a full dual 2.25" setup with high flow cats and a magnaflow muffler...it's almost as annoying as your mom nagging you to clean up your room under cruising conditions.

On a more serious note, if you're concerned about freeing up some HP by modding the exhaust, just do the piggie pipe mod to the downpipes or buy some piggie pipes. (requires welding and some violence with a hammer and chisel). After the cats...do whatever you like the sound of.

Piggies

The coilovers are a good Idea. I'm running KW Variant 3's.

dineshkigul

very cool post .

janepaul

nice one...very useful..thanks for sharing..