Here is a way to have both a quiet, neighborhood friendly exhaust for street driving and a full out performance exhaust when you are headed to the track.
My Dynomax Turbo mufflers are street friendly, plus I can listen to the radio and the wife (when I choose too.) My dragstrip class requires a muffler. I wanted a more performance oriented one and thus purchased a pair of Dynomax Race Bullets. Race Bullets are 12” of pure exhaust noise/horsepower and are geared solely for track performance. They are not really considered streetable and John law will have a fit due to the excessive noise. Here is what I did to satisfy both my street and strip cravings:
I purchased 4 sets of 2 ½” header reducers to match my existing exhaust and a pair of Race Bullets. The header reducer kit from Summit is very complete and includes the gaskets and hardware. See Figure #1. For this project, the reducers will be bolted together and installed in pairs. Once completed, I will be able to remove the muffler (or the H pipe/tailpipes with ease.)
Figure #1
Figure #2 shows the stock exhaust before the Race Bullets were installed.
(Note: The tailpipes shown already have a sets of header reducers installed, but for the purpose of this article we will assume that they do not yet exist.) Figure #3 shows a Race Bullet.
Figure #2
Figure #3
I determined where I wanted to install the Race Bullets and marked the location on my exhaust using a permanent marker. I also determined where I wanted to use the header reducers to create the removable connection. Next, I used my sawsall and cut the pipe to remove my existing exhaust. One cut was at the rear of the muffler and the second was where I wanted to mount the Race Bullet. I left the tailpipe hanging in place. I then mounted the Race Bullets as far forward as my existing exhaust and the driveshaft tunnel clearance would allow. Next the whole H pipe was removed for welding--you can use clamps if desired. For my purposes, I wanted to keep the Race Bullets installed permanently so I welded them permanently in place. At the Race Bullet's outlet, I installed one pair of header reducers. See Figure #4 and Figure #5.
Figure #4
Figure #5
Next I added one header reducer to each tail pipe. See Figure #6. The Turbo Muffler will have a matching reducer installed that will mate to the tail pipe. The front of the Turbo muffler will be connected to the header reducer already installed on the rear of the Race Bullet.
Figure #6
The H pipe, Race Bullet, and header reducer combo were reattached to the headers. Figure #7 shows them being supported under the car.
Figure #7
The Turbo muffler is now installed between the Race Bullet and the tail pipe. Careful planning and attention to detail is required to create an exact fit. Notice the alignment marks found on the piece of pipe in front of the Turbo muffler. See figure #8.
Figure #8
Figure #9 shows the left side exhaust which is now complete. Note how the Turbo muffler can now be easily removed just by unbolting the header reducers.
Figure #9
There are other “options” available. Figure #10 shows a readily available header collector extension which could be trimmed and installed in place of the turbo muffler if you want to run tailpipes. It is a perfect match to replace the Turbo muffler's offset inlet/center outlet. Figure #11 shows a 90 degree section of pipe that could be bolted to the Race Bullet to allow the exhaust to exit in front of the rear tires. The Race Bullets could have also been installed in the same location as my Turbo muffler, but there would be somewhat of a performance loss due to the excessively long pipe leading to them.
Figure #10
Figure #11
Conclusion:
Having a street/strip car does not mean that you have to terrorize your neighborhood with loud exhaust, nor be limited to driving it solely at the track. With a few modifications to your existing exhaust, your car can remain a dual purpose vehicle without sacrificing driveability or performance.
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Dennis
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65' STANG (3330 lbs), 393W NA, Toploader 4 Spd, 4:11, AFR 205's, Vic Jr. Intake, CI Custom SFT, 750dp, 11.0 CR
11.25@122.19mph
Today
