BIG exhaust's????
Discussion
Just a quick question, are they worth it???
Was behind a BMW wanna be m3 with 2 great tail pipes coming out of the back today and it was sooooo loud!!
I say it was a wanna be, had all the bits but didn't look right, and could keep up with him in my work van 2.0 tdi astra!
These always seem to be on crap cars apart from a couple i've seen and heard on subaru's.
Is there a big power gain??? Are they that loud inside the car and if so why are the owners not deaf?
I'm all for a nice sounding engine, Tvr especially
, but on smaller cars? Don't get it.
Was behind a BMW wanna be m3 with 2 great tail pipes coming out of the back today and it was sooooo loud!!
I say it was a wanna be, had all the bits but didn't look right, and could keep up with him in my work van 2.0 tdi astra!
These always seem to be on crap cars apart from a couple i've seen and heard on subaru's.
Is there a big power gain??? Are they that loud inside the car and if so why are the owners not deaf?
I'm all for a nice sounding engine, Tvr especially
, but on smaller cars? Don't get it.
Actually, I am looking for advice on the exhaust matter for an M3 E46.
I have been a fan of Tubi systems on the Ferraris but think its too Raspy on the M3, very tinny at the high end. I think I'm looking for more 'flexible' sounds ie. progressive changes in the exhaust note through the rev range.
Ferrari / Tubi have this sorted! 355 or 360 accelerating from standstill has dynamic changes and builds in the exhuast note from bassy woofle low down through to F1 type howl at the high revs. Tubi maybe sounds better on a V8 than a V6, hence I didn't like it on an M3.
Any advice greatly appreciated from people who have first hand experience.
I have been a fan of Tubi systems on the Ferraris but think its too Raspy on the M3, very tinny at the high end. I think I'm looking for more 'flexible' sounds ie. progressive changes in the exhaust note through the rev range.
Ferrari / Tubi have this sorted! 355 or 360 accelerating from standstill has dynamic changes and builds in the exhuast note from bassy woofle low down through to F1 type howl at the high revs. Tubi maybe sounds better on a V8 than a V6, hence I didn't like it on an M3.
Any advice greatly appreciated from people who have first hand experience.
g wonderfull!!!!
Exhausts vary so much from car to car and why they are the way they are.
Usually, exhausts cool the gas, and as it cools, it contracts. As it contracts, it can slow down to keep the same volume going through.
So, have a huge pipe right to the end, and the gasses cool down by half way quite alot, and then slow down since there is nothing pressing against them. This isn't so good for power and adds back pressure.
A good system gets a bit smaller along it's length, so the gasses stay warm, and actually want to escape to the lower pressure outside the tail pipe.
That is usually taken care of by having a 2.5 inch pipe all the way, then a huge end bit off the rear silencer. It's not that big all the way and does nothing for power!
As for turbo cars using a big exahust, same applies. Can't reduce back pressure when the turbo blocks up the exhaust worse than anything else already. Best to optimise the flow after the turbo, hot relatively high pressure gasses. However, the turbo gets hot, and so does the pipe behind it, so usually the exhaust gas temps are higher, so you can use a bigger pipe without it cooling as fast, which helps power somewhat.
A car I run, a Sierra XR4x4 has cast manifolds, and when people made them have LESS back pressure, they ran cooler, and this in turn, made the heads run cooler, so the engine didn't run as hot, which in turn made the whole lot run worse, even though it was better breathing.
Only way around that is to alter the thermostat probably, but that may make the bottom end run hotter just to get the heads warm enough.
All a big balancing act. To get the best costs lots of dosh.
Best change for a NA car is to make sure it's well maintained and change the cams in it.
Best for a turbo is bigger intercooler and more boost.
Hmmmm
Dave
Usually, exhausts cool the gas, and as it cools, it contracts. As it contracts, it can slow down to keep the same volume going through.
So, have a huge pipe right to the end, and the gasses cool down by half way quite alot, and then slow down since there is nothing pressing against them. This isn't so good for power and adds back pressure.
A good system gets a bit smaller along it's length, so the gasses stay warm, and actually want to escape to the lower pressure outside the tail pipe.
That is usually taken care of by having a 2.5 inch pipe all the way, then a huge end bit off the rear silencer. It's not that big all the way and does nothing for power!
As for turbo cars using a big exahust, same applies. Can't reduce back pressure when the turbo blocks up the exhaust worse than anything else already. Best to optimise the flow after the turbo, hot relatively high pressure gasses. However, the turbo gets hot, and so does the pipe behind it, so usually the exhaust gas temps are higher, so you can use a bigger pipe without it cooling as fast, which helps power somewhat.
A car I run, a Sierra XR4x4 has cast manifolds, and when people made them have LESS back pressure, they ran cooler, and this in turn, made the heads run cooler, so the engine didn't run as hot, which in turn made the whole lot run worse, even though it was better breathing.
Only way around that is to alter the thermostat probably, but that may make the bottom end run hotter just to get the heads warm enough.
All a big balancing act. To get the best costs lots of dosh.
Best change for a NA car is to make sure it's well maintained and change the cams in it.
Best for a turbo is bigger intercooler and more boost.
Hmmmm
Dave
Hi new on here but thought that I would add my 2 cents. I run a E46 M3 and have just had a full Supersprint Lightweight system fitted ( racings kats, unsilenced x pipe and back box ) and the difference is unbelievable. Car feels a lot more urgent now right through the rev range and of course the sound is fanatastic.
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