Installed Magnaflow Quad Amazing!!!!!!!
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Originally Posted by TX-T.Silver' post='634278' date='Jul 28 2008, 01:12 PM
I don't know if this has been asked/discussed elsewhere, but here goes...
After changing from a 2 exhaust to a Quad, what should one expect with horsepower and torque. I know the thought is that by adding the extra exhaust outlet, you should be reducing backpressure and therefore have an increase in HP. But is this truely the case? Also what about torque?
I don't know if the BMW stock exhaust has been designed specifically for the engine, so that when you go mucking around and changing things, you actually end up hurting yourself in the area of HP and torque.
Also, does it matter if the engine is a V8 or I6 TT, etc??? I don't want to go through the expense only for looks!!
After changing from a 2 exhaust to a Quad, what should one expect with horsepower and torque. I know the thought is that by adding the extra exhaust outlet, you should be reducing backpressure and therefore have an increase in HP. But is this truely the case? Also what about torque?
I don't know if the BMW stock exhaust has been designed specifically for the engine, so that when you go mucking around and changing things, you actually end up hurting yourself in the area of HP and torque.
Also, does it matter if the engine is a V8 or I6 TT, etc??? I don't want to go through the expense only for looks!!
anyone?
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Originally Posted by TX-T.Silver' post='634379' date='Jul 28 2008, 02:45 PM
anyone?
TX,
Straight-throughs used in quad will increase exhaust velocity (thus less pressurization or what most people call backpressure) will give you a couple of HP in high speed, e.g. 80+ mph acceleration. However, the same straight-through designs will reduce the low-end torque because it reduces the scavenging effects (on the engine pistons). The reduction is minimal, but most people will feel it. I hope you understand what I'm talking about. The effects of aftermarket straight through design mufflers is a louder exhaust note. Some people consider it a nuissance while others like it.
Hope that answers your question.
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Originally Posted by Bimmer32' post='634792' date='Jul 29 2008, 12:25 AM
TX,
Straight-throughs used in quad will increase exhaust velocity (thus less pressurization or what most people call backpressure) will give you a couple of HP in high speed, e.g. 80+ mph acceleration. However, the same straight-through designs will reduce the low-end torque because it reduces the scavenging effects (on the engine pistons). The reduction is minimal, but most people will feel it. I hope you understand what I'm talking about. The effects of aftermarket straight through design mufflers is a louder exhaust note. Some people consider it a nuissance while others like it.
Hope that answers your question.
Straight-throughs used in quad will increase exhaust velocity (thus less pressurization or what most people call backpressure) will give you a couple of HP in high speed, e.g. 80+ mph acceleration. However, the same straight-through designs will reduce the low-end torque because it reduces the scavenging effects (on the engine pistons). The reduction is minimal, but most people will feel it. I hope you understand what I'm talking about. The effects of aftermarket straight through design mufflers is a louder exhaust note. Some people consider it a nuissance while others like it.
Hope that answers your question.
Thanks for the info. It makes sense. I am planning the quads for the looks mostly but didn't know if I would sacrifice too much in the performance category.
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My Ride: 2006 550i Black Saphire/Black Dakota Leather- Loaded- M5 Appearance Package, Sport Package, Pro logic 7 Premium Sound, Navigation, Cold Weather Package, Comfort Package, Heads-up Display, park Distance Control, Bluetooth, Active Steering, Electric Rear Sunshade, Rear Folding Seats, Front/Rear Heated Seats, Xenon lights, Satelite Radio- Extended Maintenance, CPO (Considering Tire/Wheel Insurance)
Originally Posted by tbal' post='632175' date='Jul 25 2008, 02:15 AM
You are absolutly right... I just did the magnaflow exhaust on my 645... sounds sweet, but not close to any american v8 cars.... My friends actually have magnaflow exhaust on their, corvette, mustang, and such but sounds nothing like my car...
One things for sure, ppl turn heads as the euro v8s make a very distinctive growl...
One things for sure, ppl turn heads as the euro v8s make a very distinctive growl...
So, I have the 550i...Can Ido the same magnaflow for an 8 cyl?
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05 530i A36w/ Beige interior: DVD/mp3 player,
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Performance: Bilstein PSS9, GroppeM intake, Supersprint pipes, ECU remap, Brembo front-380mm, back-345mm
Originally Posted by NeRwEEzy' post='600522' date='Jun 12 2008, 01:23 AM
PM sent
NeRwEEzy, can i have the PM as well?
thanks~~
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