The new exhaust is done, and...
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The new exhaust is done, and...
...and since some of y'all have been asking about it, I figured I would give a description of the finished product. I typed something very similar to this a few days ago, but somehow it didn't make it to the forum. I hate my university's network.
For those who are unfamiliar, this exhaust is similar in most ways to the systems installed by Riski/bfsgross/others -- 2.5" stainless steel piping, Magnaflow hi-flow cats and mufflers, factory resonator deleted. X-pipe installed. Resonated 3.5" tips.
Ok...at idle, from the outside, the car sounds absolutely great -- a very low, authoritative rumble. Inside the car, at idle, it is not loud but the exhaust note can be heard easily.
I feel that, when moving from a stop, there is some *loss* of power/torque at the 'low end' (so to speak)...but this is easily compensated for by what feels like a significant power increase at all RPMs above 2500.
Without the resonator, the exhaust is slightly louder than I had hoped for...but still quieter than the Corvette I had (with straight piping). My wife told me that she would whip my @$$ (haha) if the Jaguar ended up as loud as the Corvette, and so far my @$$ is essentially unwhipped.
One complaint I have about the exhaust note is that, at WOT with RPMs under 4000 or so, there is a strong metallic tapping sound that I can only describe as similar to what valve tapping sounds like, but amplified...It is not audible at moderate acceleration or at idle. This tapping is not audible from the passenger seat, for some reason. Also, the supercharger whine is not necessarily audible from the driver's seat, but can be heard on the passenger side. Strange...
At least once since the exhaust was completed, it appeared that the exhaust note alone has caused a mischievous BMW driver to reconsider testing my STR's capabilities. He looked confused as he decided to pass me slowly while staring at my hood area.
Total cost of this project was about $800, including labor.
For those who are unfamiliar, this exhaust is similar in most ways to the systems installed by Riski/bfsgross/others -- 2.5" stainless steel piping, Magnaflow hi-flow cats and mufflers, factory resonator deleted. X-pipe installed. Resonated 3.5" tips.
Ok...at idle, from the outside, the car sounds absolutely great -- a very low, authoritative rumble. Inside the car, at idle, it is not loud but the exhaust note can be heard easily.
I feel that, when moving from a stop, there is some *loss* of power/torque at the 'low end' (so to speak)...but this is easily compensated for by what feels like a significant power increase at all RPMs above 2500.
Without the resonator, the exhaust is slightly louder than I had hoped for...but still quieter than the Corvette I had (with straight piping). My wife told me that she would whip my @$$ (haha) if the Jaguar ended up as loud as the Corvette, and so far my @$$ is essentially unwhipped.
One complaint I have about the exhaust note is that, at WOT with RPMs under 4000 or so, there is a strong metallic tapping sound that I can only describe as similar to what valve tapping sounds like, but amplified...It is not audible at moderate acceleration or at idle. This tapping is not audible from the passenger seat, for some reason. Also, the supercharger whine is not necessarily audible from the driver's seat, but can be heard on the passenger side. Strange...
At least once since the exhaust was completed, it appeared that the exhaust note alone has caused a mischievous BMW driver to reconsider testing my STR's capabilities. He looked confused as he decided to pass me slowly while staring at my hood area.
Total cost of this project was about $800, including labor.
Last edited by Phil_Deeznuutz; 10-06-2010 at 02:39 PM. Reason: added x-pipe
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Phil, yes the stock piping is 2.25". I believe mafioso means to be "different" as in retaining the stock pipe diameter. This may allow a little less of a loss of bottom end torque. And...Awesome!, you did it. Yes, you'll feel a slight loss of torque at low rpm's but as you already have noticed more torque and horsepower above 2500 rpm. The tapping sound under acceleration is exhaust gas escaping into a much less restrictive environment...banging off the walls of the pipe. You're again on the money with a hard re-set of the ECU. Do this to purge old info. and let her re-learn her new capabilities. Now here's your bonus...pop on a 1.5 pulley (or smaller) and a low temperature thermostat, and ye shall recieve more torque on both the low end and midrange than before you "Exhausted" her. I also strongly suggest yas tune the ECU via what is available through Eurotoys, etc., or better; a reputable dyno-tuner. Here, we'll unlock modest amounts of horsepower and torque. Most us have read ECU tuner literature claiming an ECU tune and a cat-back exhaust mod on a basically stock STR developed 440 hp and 488 lb/ft of torque (a gain of 50 hp & 80 lb/ft trq.). You have better: An exhaust manifold-back exhaust mod. Imagine what a smaller pulley, etc. could do for power building on top of your full exhaust mod? My STR screams compared to stock. On the way to work this morning a "built" 1986 Mustang GT took a thrashing. He must have been very surprised to quickly see my brake lights...and he had 700 pounds "less" weight to move!
Last edited by bfsgross; 10-07-2010 at 12:10 PM.
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I was under the impression it was 2" if it's 2.25 hmmm I can Frankenstein the exhaust as a test. Goto spun cats, pull the resonators off take it to magnaflow free flow mufflers I go today for a base pull on the dyno then after the exhaust done get another pull on the dyno and see where I'm at with it.
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Can't do it just yet. I'm a numbers guy so now that the tune up is done ( plugs cops all filters fresh oil (motor tranny rear end) new u2 senors (all replaced)) it's time to get a baseline then the mods ;-)
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Shoot! it's in the 50's and drizzlin here in eastern NY. I'm very close to either sending out the ECU for a tune or hooking up with a dyno-tuner who's interested in developing a program for STR's. I'm acheing to learn what your dyno-run turns up. Keep up the good work Mafioso.
Last edited by bfsgross; 10-07-2010 at 03:41 PM.
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