Straight pipe = no power - PeachParts Mercedes-Benz Forum

mach0415 · #1 11-23-2010, 04:59 AM

I have been reading about exhaust mods on OM617s and so just to tickle the fancy of some of my students, we took the factory mufflers and resonator off the 300SD yesterday, in class to check out the sound. Sounded great, but where did the power go? Needless to say, the exhaust was put back on and will stay on. Is this normal?

vwbuge · #2 11-23-2010, 05:29 AM

When my straight pipe was installed I made other mods at the same time. So I can't say the pipe alone was the cause for my power increase. I am sure it did not rob it of power though. It may not make MORE power but the power will come on quicker as the turbo will have less resistance.

mach0415 · #3 11-23-2010, 05:32 AM

I did notice the turbo spooling up quicker at 1500, but there is a definite power loss. I know this does not make sense, since the turbo helps make the power.

oldsinner111 · #4 11-23-2010, 06:10 AM

I'm straight piped,I noticed more power.I modified air intake and made sure I had a 90% bend in it.That bend produces the tire chrip.

KarTek · #5 11-23-2010, 06:14 AM

Did you do any performance tests? 0-60, etc... It's been my experience that when you suddenly remove the muffling on a vehicle, there's an instant perception of performance loss because the noise for any given situation is increased.

Your brain is saying: "Why is the engine working so hard and I'm not going anywhere."

The same goes for muffling a louder vehicle. As soon as you put it on, there's this feeling like the car is flying.

pawoSD · #6 11-23-2010, 07:22 AM

Power loss? Yeah right. I have to be quite careful in the wet with my straight pipe, as it spools up quite fast and easily breaks the tires (good michelins!) loose.

My car is mighty quick for a 300SD, and all it has is a 2.5" pipe from front to back.

vwbuge · #7 11-23-2010, 07:49 AM

Quote:

Originally Posted by pawoSD

Power loss? Yeah right. I have to be quite careful in the wet with my straight pipe, as it spools up quite fast and easily breaks the tires (good michelins!) loose.

My car is mighty quick for a 300SD, and all it has is a 2.5" pipe from front to back.

Same here. I DO NOT enjoy driving mine in the wet.

mach0415 · #8 11-23-2010, 07:54 AM

Maybe it is a figment, then. Did you all leave the rear muffler and do away with the midship kidneys?

mach0415 · #9 11-23-2010, 07:55 AM

also, I am thinking about simply splicing the rear muffler to the middle pipe. What size is this middle pipe? 2 1/4?

MTUpower · #10 11-23-2010, 08:23 AM

The rear is the muffler, the front is the resonator. Leave the resonator, delete the muffler. I'd put money on that you have more power and sooner, but your perception is that you have less.

mach0415 · #11 11-23-2010, 08:25 AM

How about sound? I was not that impressed with just the muffler off.

MTUpower · #12 11-23-2010, 08:29 AM

Quote:

Originally Posted by mach0415

How about sound? I was not that impressed with just the muffler off.

You need the resonator to stop the drone, and a downturned tip exit- the sound is more truck like for lack of a better word, but not really much louder.

mach0415 · #13 11-23-2010, 08:31 AM

Can you hear turbo chirp w/o muffler?

toomany MBZ · #14 11-23-2010, 09:06 AM

This is mine (SD) winds up, without the resonators and a stock Ansa muffler.

Cheap camera: http://www.youtube.com/watch?v=YyCE2tXoUis

Turn the radio on, you won't notice the drone.

vwbuge · #15 11-23-2010, 09:52 AM

No resonators, no muffler on mine. Just straight pipe. A little louder inside the car at idle and highway speed but no drone. Not even enough to annoy.

It is funny though, when shutting the car down I get out and walk around the back and I can hear the turbo spinning through the exhaust.

I do have to say at full throttle it does sound like a diesel.