cobalt

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.

K964

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.

wsybert

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.

cobalt

I think your right I don't have the receipts hear so more like $400 complete muffler and fabrication included.

cobalt

I just noticed all you need is a 928 GTS and we have nearly the same car collection.

Meares

K964 what chip did you use?

K964

Hey Anthony,

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

K964

I do not recall what I had on the Cup, but have a Cyntex (sp?) on my RSA (and am running the same exhaust setup as it is a track only car).

Mike

Meares

how do i " quote message in reply?"

cobalt

click on the quotation marks in the lower right hand corner.

newsboy

If you eliminate the secondary muffler, you will be noticed by your neighbors. For me it changed the sound from sports car to hot rod,. My opinion only.

ilko

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.

Meares

THANKS!!!!!!!! is been driving me crazy!

all623

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.

all623

Any recommendations on brand of cat bypass pipe I should use?