View Full Version : Muffler selection

12-31-2008, 06:26 PM
**Cliff notes: Looking for suggestions on a good performing QUIET muffler. 2.25" in and 2.25" out**

The time is getting near for me to address some of the problems my 4A-GZE powered MR2 has.

First a little history. When I bought the car it had a 4A-GZE US spec swapped into it. It still has the original NA transmission (found that out when I replaced the starter). The exhaust had the stock GZE manifold WELDED to the B-pipe, welded to the flex pipe, welded to a straight pipe (where the cat used to be), welded to a 180 degree bend, welded to a 93 MR2 turbo stock muffler. The car was loud. One day the muffler fell off and the car was even louder. I took it to a shop (was not in my hometown at the time) and they refused to do any major work to it as the whole system was welded together. I managed to convince them to put on a muffler. All they had was a stock NA muffler. Sure the car lost a little performance but it was quiet. I like quiet. Eventually the flex pipe rusted out and I welded in a cheap patch (a U-Fix-It kit from the local big box auto store). As I was unable to take the system off the car to weld it the top didnt get done. It leaks. It's loud. It's crap.

The water pump bearing recently grenaded and I replaced the pump with a new one. However I reused an old o-ring that I shouldnt have and as a result I have a small leak. The engine also has many of the common oil leaks that these cars get. So I ordered all the parts I need to stop all these leaks from kbox.ca. I have decided that I might as well do the clutch and flywheel as well. At the end of the day it is easiest to pull the motor and transmission and then I can clean it all up and get everything sealed up properly.

I will not be digging into the engine or doing a rebuild. I dont need one. But in order to get everything apart, the exhaust has to come off.

I have a 3rd generation 4A-GZE (MAP sensor, DLI, etc) from a Levin sitting in the garage. I have plans for this engine but that is a long way off. It did come with a very nice equal length header which I do not know if it is stock or not. I plan on using this and then putting together my own exhaust. I have the pipes and mandrel bends sourced.

I plan on going from the header into a 2.25" pipe, to a flex pipe, then turn towards the drivers side of the car (like stock), through a resonator, then another stock like 180 degree turn, through a muffler, and finally out. The system will follow the stock path fairly closely. I will also be using three bolt flanges for ease of installation and repair.

What suggestions do you guys have for a muffler that is quiet and free flowing. I am budgeting around $100-$150 for it. I don't need big brand names, just something that will work and last. I am looking for 2.25" in and 2.25" out. I saw one on the Magnaflow site but it is simply a glass packed muffler and I simply do not now how quiet that will be.


12-31-2008, 06:43 PM
I would look into Borla. I like them and they have a great sound. My buddy has it on is VW and sounds mean. It's not loud at all. The sound matches the engine well and has a little grunt to it. Im looking into this setup for my car!

12-31-2008, 07:03 PM
I loves my magnaflow. Mine's just the basic straight through oval muffler. It's slightly larger than the stock oval, so I don't know if you'll have issues on that MR2, but it went right into the original location on the coupe, 2.5" pipe and all.

As for quiet... It isn't extremely loud by any means, but it is much louder than the stock system. I replaced the two original long resonators with one short one as well, so that added to it a bit.

I love how it sounds though, and personally I think it would sound freakin' amazing on that GZE. :)

01-01-2009, 12:39 AM
MagnaFlows aren't glasspacks. They are a straight-through design, but rather than using a louvered inner pipe as you'd find on 50s-era glasspacks (and current Cherry Bombs), they use a smooth perforated tube. The insulation is a ceramic mat backed by stainless steel wool, which means it does not break down and blow out as fibreglass insulation does.

The benefit of a straight-through design is that you can get a longer and quieter muffler without compromising exhaust flow (or doing it so minimally you could not notice on a dyno).

01-01-2009, 07:08 PM
One of the advantages I have with the MR2 is that the muffler can be rediculously long as it has a large space under the rear trunk. So if I were to go with a Magnaflow I would assume that the longer the better in terms of quietness? One problem I have is I would really like to know how it sounds with my engine before purchasing....

01-02-2009, 04:46 AM
I could take some audio of mine, but I doubt it would be close enough.

01-02-2009, 05:42 AM
Any audio would be appreciated. I've been looking around youtube to try and find even a 4age with a magnaflow on it in the hopes of hearing something close to what mine might sound like. So far no luck. I'm not terribly rushed though, I am getting everything needed together first. It will probably happen somewhere in the February to May range.