How much additional hp would a Milltek Exhaust w/ K&N drop in filter combo produce?
#1
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10? 15? What kind of future mods may be available for the S5 that will increase the hp to ~380?
#3
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Generally true, with very few exceptions. On my E39 M5 I got a 10% increase (35rwhp) by replacing the stock headers with Supersprint (Dinan achieves the same despite a different design). The stock headers were very flawed in terms of design, with 2 collectors merging together into one downpipe at a 90degree angle, which restricted air flow immensely. Basically it was the same as in the 540is as BMW cut some R&D costs and never bothered developing a true optimal header system for the S62 engine.
This was the biggest bang for the buck in terms of bolt-on mods (albeit still very expensive), and depending on the design, headers may or may not contribute as much gains across other applications. However things like cold air intakes, cat back exhaust, filters only add (low) single digit hp, if that.
This was the biggest bang for the buck in terms of bolt-on mods (albeit still very expensive), and depending on the design, headers may or may not contribute as much gains across other applications. However things like cold air intakes, cat back exhaust, filters only add (low) single digit hp, if that.
#5
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I second that. On many applications (like on my car), K&N's oiled-surfaced air filters have proven to polute the MAFSs. Not worth it for a mere few hp.
#6
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apparently they were getting about 25bhp with the replacement of downpipes and cat/back on that car. One site even reports 35bhp dyno tested. There is no downpipe available for the S5 today, but Im sure it will be along soon. I wouldn't doubt that the Milltek provides at the minimum a 10bhp gain on it's own (without the downpipes). I believe Roswell mentioned about the same in a thread below.
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#9
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I agree also, do not use an oiled filter. It will give you no more HP and it will foul your MAF which is not cheap to replace.
If just changing the air filter could actually give you more HP the auto manufacturers would have changed their design years ago.
If just changing the air filter could actually give you more HP the auto manufacturers would have changed their design years ago.
#10
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<center><img src="http://pictureposter.audiworld.com/70547/2004_s4_dyno.jpg"></center><p>This is based on a totaly stock S4 puting down 255 whp on the same type of dyno, under similar conditions.