[Iwantm3]

Does muffler delete voids waranty ? and what's better muffler delete or cat delete power wise ? thanks

[BoostedCosta]

anthing can void the waranty lol depending on your dealership
and by deleting the cats you will get more power than deleting the mufflers

[Jonny550]

I have the muffler delete and the power gains were not all that great 10-12 whp probably and a very nice tone.Cutting the cats would make the car sound like a killer from hell.No matter what you do to your car BMW will try their hardest to fuck you for it i have done a shitload of service work on my car with the muffler delete and intake installed and they never said anything.

[bavarian19]

I think muffler delete getting anything more than 3-5 hp is probably


If you have 335, going with an aftermarket tune or jumping up the map is probably the best way to gain hp.

[E92-Lighting]

i love the sound after the muffler delete, aggressive.....

[balance]

i don't know about powerwise but muffler delete sounds pretty good but be prepared to get some major headaches
your going to have to listen to music real loud on the freeways because drone is like HELL

[E92-Lighting]

i forgot to mention, you will have to get used to the drone sound... but i am sure you will get used to it eventually

[cstavaru]

Originally Posted by Takashi

Think about it. If going with a muffler delete will increase hp, then all the cars advertised in fast and furious will have no muffler.

Maybe they don't want to attract cops ?

[Jonny550]

Originally Posted by Takashi

How many test runs did you do?
Are the environmental conditions the same?
Is it the same vehicle?
What type of gasoline were you using? Was it the same tank?
Who was the operator of the car?
Was the person doing the testing properly trained?
Was all the settings correct?

I am not the only one who is questing your data and test method. I am just stating the facts. If listing out the facts make me a smart ass, then there are tons of smart ass around here which leaves you the only one who is not.

Better provide some hard data to support your claim or else there are going to be a lot of people telling you the same thing.

I didnt think i needed to get hard evidence to tell you something i know but in all honesty being cocky never makes anyone reply to your post nicely.If you dont belive me and disagree you should have asked me the above questions like a fellow BMW enthusiast would not like a smart ass. And i would have answered them


1.Same temp around 82-83 degrees
2.is it the same vehicle? their you go being cocky<----
3.what type of gasoline was you using ? 93 octane...No it wasnt the same tank it was a different tank of gas
4.Operator was me both times
5.was the testing being done by a pro? yes
6.was all the settings correct ? not sure but iam pretty sure it was good.



dyno pre muffler delete 367.4 RWHP 355 rwtq
Dyno post muffler delete pull 1------375.3 rwhp 356.2 rwtq
dyno post muffler delete pull 2 ------377.1 rwhp 354 rwtq


all dynos were done on map 6 with a with an intake.

[pruettfan]

To me the drone is miserable on cars with muffler delete. They always sound cool for a while but if you drive the car everyday it will get old quick.

[Jack be Quick]

Muffler delete typically WILL create a minor level of horsepower increase; 3 to 10 depending on size of motor and overall restriction of the exhaust.

It typically also may decrease torque. The reduction in back pressure can affect torque. It's been proven over and over on dyno runs.

A high performance muffler will give you a power increase, reduce impact to torque and normally keep sound to a tolerable level.

The sound of the muffler delete on the 335 is pretty good - I've posted video previously. It will create a drone.

I switched from the muffler delete to a set of Billy Boat twin mufflers. Guess what, the drone is as bad if not a tad worse with the Billy Boats then the muffler delete! The advantage of the BB over muffler delete is that once the RPM is high enough the mufflers will quiet down. The muffler delete will never quiet down. So, at highway speed above 83 the BB quiet right down. Regret the days that traffic on the highway is bad and your forced to drive at 65-75 an extended period of time.