964 Muffler Advice Needed
#16
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I put a 100 Cell cat to keep my car legal and eliminated both primary and secondary mufflers and replaced them with a magnaflow which required custom fabrication to fit. Although I can replace either the primary or secondary with this setup. Sounds great semi quiet at idle and gets progressively louder as you approach WOT. Still not obnoxiously loud, no drone at constant RPMS and seems to have improved performance. Overall sound is a little quieter at idle and a little louder at WOT than it was with the secondary bypass and cup air box.
Muffler was around $400 or less with a nominal fabrication charge. My shop uses the magnaflow in lieu of the Borla units now. They found them to perform better and cost far less. All SS construction and lifetime guarantee.
Muffler was around $400 or less with a nominal fabrication charge. My shop uses the magnaflow in lieu of the Borla units now. They found them to perform better and cost far less. All SS construction and lifetime guarantee.
#17
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My former Euro Cup had the Euro pre-muffler, primary bypass, and secondary bypass. Bob Scotto (fstockcarrera here on RL) performed extensive testing on every conceiveable muffler combination and found that the above setup yielded the most advantageous results for a GTC-1 track car. As far as I know, all the GTC-1 racers go with this particular setup. To fully take advantage of these mods, you'll want to upgrade the chip as well.
#18
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I put a 100 Cell cat to keep my car legal and eliminated both primary and secondary mufflers and replaced them with a magnaflow which required custom fabrication to fit. Although I can replace either the primary or secondary with this setup. Sounds great semi quiet at idle and gets progressively louder as you approach WOT. Still not obnoxiously loud, no drone at constant RPMS and seems to have improved performance. Overall sound is a little quieter at idle and a little louder at WOT than it was with the secondary bypass and cup air box.
Muffler was around $400 or less with a nominal fabrication charge. My shop uses the magnaflow in lieu of the Borla units now. They found them to perform better and cost far less. All SS construction and lifetime guarantee.
Muffler was around $400 or less with a nominal fabrication charge. My shop uses the magnaflow in lieu of the Borla units now. They found them to perform better and cost far less. All SS construction and lifetime guarantee.
The Magnaflow is a full stainless, straight through design. It is also smaller than the stock primary. Total cost was around $200 (if I remember correctly), but I did all the fab work.
Sounds really great, IMO.
#19
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Very similar to mine. I replaced both of mine with a Magnaflow, and custom fabbed the connection and outlet. I still have the stock cat, but it may be coming off when the engine goes back in.
The Magnaflow is a full stainless, straight through design. It is also smaller than the stock primary. Total cost was around $200 (if I remember correctly), but I did all the fab work.
Sounds really great, IMO.
The Magnaflow is a full stainless, straight through design. It is also smaller than the stock primary. Total cost was around $200 (if I remember correctly), but I did all the fab work.
Sounds really great, IMO.
#20
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My former Euro Cup had the Euro pre-muffler, primary bypass, and secondary bypass. Bob Scotto (fstockcarrera here on RL) performed extensive testing on every conceiveable muffler combination and found that the above setup yielded the most advantageous results for a GTC-1 track car. As far as I know, all the GTC-1 racers go with this particular setup. To fully take advantage of these mods, you'll want to upgrade the chip as well.
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#22
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Funny you mention that---a friend is selling his '87 928S-4 and is hounding me to buy it. The car has 50k miles, Black with cashmere interior, 18" wheels, blah, blah blah.... and is a 5 speed.
Decisions.....decisions.....
Mike
#23
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#27
Agent Orange
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I have the Fabspeed no cat, no heat exchangers, dual outlet muffler. It sounds great! I'm sure it adds some horsepowers and torques but I can't tell, because my engine is not stock at all. On the Fabspeed site it says it is 42 lbs lighter than stock so if that's all I gain I'm happy with that.
#29
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The sound clips would be great if it's convenient to post.
Also, the Joel Reiser quote is helpful. I do plan to do some track work with the car and the torque is more important than top speed in my case.
Also, the Joel Reiser quote is helpful. I do plan to do some track work with the car and the torque is more important than top speed in my case.