"Fixing" M2 Exhaust - Lexus IS Forum
User Tag List

 
LinkBack Thread Tools
post #1 of 5 (permalink) Old 09-08-2012, 10:12 PM Thread Starter
Newbie
 
Join Date: Apr 2007
Location: West Bloomfield, Michigan
Posts: 14
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
           
Garage
"Fixing" M2 Exhaust

This may be of use to those of us who own or have though about purchasing the inexpensive M2 exhaust for your ISx50, but have been hesitant from the negative reviews we have seen here.

I purchased the M2 exhaust for my 2008 IS350 last year after reading some mixed reviews here, at the time it was so cheap on eBay I thought I would give it a try.

It sounded great at idle, but during acceleration it was a little louder than I would have liked and it droned during highway travel, much as many people have also complained about here. So after a few weeks I took it back off.

This year after getting tired of looking at the M2 sitting in my garage, I spent some time researching into where the droning was coming from and did some acoustic tests on it playing specific frequencies through it from a speaker and frequency generator and ended up finding a lot of resonances within it. The resonances were specifically from the pipes, not the mufflers themselves. I also noticed that simply by holding the pipes with my hand, I could suppress many resonances I had been hearing. As a test I bolted a few pieces of steel bar with U bolts to the pipes at about midpoints to each muffler. As expected, many of the resonances had gone away.

Adding mass to exhaust systems is nothing new, I spent some time researching this as well and it is common for OEMs to do the exact same thing on vehicles to remove certain resonances and vibrations at specific rpms within the exhaust system. Looking at the stock IS350 exhaust, it actually has one itself. On the drivers side muffler there is a large rubber bushing clamped onto the back of the muffler that has no apparent function other than to suppress resonances.

So tonight I finally had time to swap out the exhaust again and the additional wights on the M2 have made a huge improvement. Acceleration sounds much more subdued, still louder than stock but significantly attenuated compared to the 'unmodified' M2. The droning at cruising is significantly quieter as well. With the addition of the weights to the M2 pipes I am definitely keeping this exhaust on the car.

The total weight I added is only about 3 pounds. Even with this the M2 weighs a lot less compared to the stock IS350 exhaust. Most of this weight is in the pipes. If you were to take any metal object and tap the stock exhaust pipes then the unmodified M2 pipes, you can hear a huge difference due to the thicker steel pipes the stock exhaust has. The stock exhaust sounds 'dead' compared to a ringing from the M2. With the weights, the M2 is much more dead when tapping as well.

Total cost for this modification was about $20. $12 was the cold rolled steel bar I purchased from onlinemetals, and a few U bolts from a local hardware store. If anyone is interested in this modification I can take some pictures showing how I added the weight onto the pipes. The weights cannot be seen as they clamp onto the front of the pipes, looking from the back of the car. I highly recommend this to anyone with the M2 exhaust that wants it to be better sounding.

2002 IS 300 L-Tuned (factory)
2008 IS 350 (sold)
2014 IS 350 F-Sport
bradthx is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 09-09-2012, 10:18 PM
Newbie
 
Join Date: Apr 2012
Location: San Diego, CA
Posts: 12
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
Definitely post some pictures! I plan on buying an M2 soon because I can't justify paying 800$ for the HKS.

2007 IS350 SGM

F-Sport RSB|20% tint|19" staggered XIX wheels|Res/muffler delete|Blue interior/mirror LEDS|Xenon Depot 5K HID lows|H&R Springs|F Sport replica grill|Blacked out emblems| DIY F-Sport Intake|Weathertech visors|CF wrapped interior| Blue Hella Supertones|JoeZ intake pipe|GT Spec STB
Toxicxk23 is offline  
post #3 of 5 (permalink) Old 09-12-2012, 12:42 PM
Newbie
 
Join Date: Oct 2011
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
Pics or didn't happen!

Haha... please?
EADGBE is offline  
 
post #4 of 5 (permalink) Old 01-31-2015, 06:21 AM
Newbie
 
Join Date: Jan 2015
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
 
Could you send me pics or exact sizes of clamps and steel you used?
Annieandy15 is offline  
post #5 of 5 (permalink) Old 08-16-2015, 11:11 AM
Newbie
 
Join Date: Dec 2014
Posts: 14
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
 
Hey bradthx, I just got the same exhaust set up. And I have terrible drone at 2300-2600 rpm. I want to try the same solution as you did. Can you post some pictures here? Would appreciate it
olDGlo is offline  
Sponsored Links
Advertisement
 
Reply

  Lexus IS Forum > 2nd-Gen IS250/IS350 > Go Fast Stuff

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Lexus IS Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself. If your address is invalid, you will likely lose access to the site.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Current users viewing this Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome