Re:catalytic converters (archive)

Thanks so much Jim! I've printed up what you wrote here so I can refer to later, I already have a cat back Remus Exhaust system on my car plus a Dinan Chip, I assume what you said will still work for me? Thanks again and I'll let you know how it works out for me, I'm still looking for some tuned header pipes but one step at a time I guess.

Jim ;-)

Dynomax hi-flo cats fit under the car (tight). I have just installed two of them on my 93 850 auto. You need pt number 15145(2 1/4in) or 15146 (2 1/2in). Dont get turned off by the price, they are cheap but they FLOW. Expensive isnt always better. I had no cats before and felt no power loss with the 2 1/2( if anything it gained a little torque). You have to trim the heat shield edges to tuck them up high in the floor tunnel.

I had an exhaust shop cut the engine pipes shorter(there are two on each side)and make a collector into one 2 1/2inch pipe, then into the cat. You need to weld in a thread for the oxygen sensor. Put a crossover pipe after the cats to join both sides of the exhaust, it gives you more midrange torque and gives you more of a ferrari sound.

The site below has all the dynomax range. The straight through "bullet" race only mufflers fit in place of the stock center mufflers, and the larger race magnum (round) can be used at the back. I have seen a number of dyno tests which proved the Race Magnum range is one of the best flowing, even over mufflers three times the price!

To finish it off, put 2 Hedman TWIN 3" chrome tips after the back mufflers. Looks ferrari. This combination WILL give you more power, and the sound is KILLER , very different to the stock set up. Oh I forgot to mention you can either go 2 1/4 or 2 1/2 after the cats . 2.5" is ok if you have chips, headers, low diff gear etc. If your car is stock , go 2.25" .

Hope this gives you some idea of what to do.

JIM G

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