Currently have a Spin Tech muffler on the car (at least I think, it is a rectangular box welded up like the spintech), and can either redo the pipe with re-using this muffler, or go to the MagnaFlow 11226 with an Allied A24.
Which is better? I'm guessing the MagnaFlow, since I can't seem to find much here about the spin tech.
Year : 1991 Posts: 396
It all depends on where you are at and how you are going to get the car to the track. I don't mind the sd exhaust but I know that everyone in my neiborhood would prefer if I did not have it on. Thankfully it is a track only car and I don't dive it on the track. Some tracks will not allow you to run over a certain decible like Leguna Seca. That beeing said I like my sd exhaist adn have been told by many that it is the best exhaust to haev at this time till someone make one better.
I have also heard great things about the SD exhaust, but run Laguna Seca and as far as I know, it is way past the Laguna requirements of 92 (or 90, I forget) dB from 50ft.
That's why I gave my two options. I have been told that the SpinTech passed Laguna sound with a 90 coming off the end, and have read that the MagnaFlow 11226 will pass as well. If it makes an appreciable difference, I will have 2 exhausts. One for Laguna, and one for everywhere else. I do not drive the car on the street, so that's not really a concern. I just need power; I found that I'm getting the run on some people out of a corner and then about 1/2 of the way down the straight they are pulling on me.
Car #: 68
Year : 91 Posts: 186
We who run Laguna Seca have decided we don't like the Allied muffler, the packing melts and plugs it up...use the SD sized Magnaflow in its place and you should make sound...Don't know about the Spin Tech.
Car #: 54!
Year : 90' Posts: 1907
What I did last year since I wasn't very performance minded is just run the stock exhaust for Laguna Seca. Sure, it probably robbed a horsepower or two, but I had a stock motor so it was no big deal.
I have the older Mazdaspeed exhaust right now, but it has a huge muffler on it. I may cut that muffler off and weld a straight through Magnaflow design onto it similar to what the SD exhaust has. This may open it up a bit (lower some weight too) and give a Hp back or so.
Region: San Francisco Region
Car #: 14
Year : 1999 Posts: 453
I had an extra Laguna exhaust section made to bolt on to the end of my SD exhaust. Used this Magnaflow muffler. You can see straight through the muffler, but nevertheless it took the sound (as measured at Laguna Seca) from ~93 dbA to ~87 dbA. Pretty amazing.
I dyno'ed the car with and without the extra muffler section, and the car actually measured a bit higher with the muffler--probably measurement noise, nevertheless it convinced me there was no reason to unbolt it. Less ballast in the passenger footwell, better sound (no more obnoxious "blat-blat"), works for me...
-------------------- Viet-Tam Luu (a.k.a. "Tam") SFR-SCCA #14 ITS Director, SCCA San Francisco Region