Just got the Hushpower HP-2 "Shortie" installed today to replace the driver's side muffler (other side still stock). I might get flamed for not doing both sides, but as I'm 30 now I don't really want a "loud / boy racer" exhaust note. The stock exhaust is just too quiet so SOMETHING needed to be done.

I'm surprised that I purchased the HP-2 seeing as I knew it would be too loud for my tastes, although it made a lot of other cars sound real throaty and that was what I was looking for. So I was compelled to giver her a whirl!

The HP-2 Shortie is marketed as both a muffler and a resonator. The body is 12" x 5" x 4" in size and in/outlet is 2.25". Hushpower also offers the regular HP-2 which has an 18" long body.





First impressions:
Great tone on start-up, idle and low RPMs. As I left the muffler shop I did notice that the car was lacking the torque it had with the stock exhaust. Although, possibly the ECU was reset during the welding process and this could account for the sluggish feel.

I didn't get a chance for WOT on the way home, but the HP-2 screams at higher RPMs. I wasn't able to really hear my F-Sport intake when laying into the gas pedal. At HWY cruising speeds there was drone, about the same as the TRD / Borla that I had on my Camry.

For normal driving the HP-2 sounded pretty good, but was simply too loud for my taste. Note: I think that all commercially available exhausts for the IS are too loud . So I will be getting a silencer placed either before or after the muffler to quiet it down, make it a bit deeper, and most importantly, get that torque back that I use in daily driving.

Being OCD with my new toy, I decided to whip up my own baffles to get the sound more to my liking until my silencer arrives. I simply took some pliable metal diamond mesh, rolled it into a tube shape, wrapped a bit of steel wool around it, and stuck it in the muffler outlet. IMO, this made the exhaust sound more subtle and slightly deeper and I thought it sounded pretty good. I took a spin and noticed that my torque was back and sound was great. I took to the HWY to see if the drone was there, and surprisingly my ghetto baffles eliminated about 80% of the drone.

First sound clip: http://youtu.be/Qfo95_c8cug (with ghetto baffles)

Wanted to get an audio clip up, but the only place I could do it without looking like a weirdo (I live downtown) was in my building's parking garage. So the sound is really amplified. There is is a wall 3ft behind me, cars on both sides, and phone placed 1 foot from exhaust.

I'll get better clips for exterior / interior / drive by, with and without the silencer up here over the next couple weeks.

 

I think the loss/gain of torque is all in your head...

So you have changed one side of the exhaust... are the outlets/tips at least matching (stock i presume)? If not, you gotta get on that!

 

I have an ISF rear end conversion (on a 350) so matching outlets and mufflers is less of an issue..

 

Sounds like a custom F-Sport style exhaust, nice!

 

I just ordered this muffler insert from Car Chemistry: http://www.summitracing.com/parts/CCI-2DI22R

Consensus from other forums seems to be that it does a good job to quiet the exhaust / eliminate drone. Although most people that have used the 3 disk insert lost a lot of hp on the high end given it's restrictiveness.

If I find this is true I'll chop off one of the disks with the Dremel and give it another shot. It also comes with some steel wool type material to pack in between the disks, so there are some options to play with to find the right balance.

 

More video clips from inside the car since I'll be slapping on a different muffler today.

Regular Driving: http://youtu.be/PToulXooRHQ

Fast Take Off: http://youtu.be/WeGgK810yMA

The muffler has a modified car chemistry insert and you'll see that there really isn't any drone at cruising / hwy speeds. So this might be an option for those that want to eliminate the drone on their exhaust.

 

Used the search and found this. I was planing on using the same Hushpower muffler/resonator. But in place of the OEM resonator. So my setup will be F-sport + Hushpower HP-2. still doing some research.