Another DACH Sport Cat Report
01-26-2009, 02:36 PM
#1
Rennlist Member
Thread Starter
Another DACH Sport Cat Report
I installed my new DACH X-Pipes with high-flow catalytic converters, so I thought I'd post my results. I bought these mainly for the sound, but also because I barely passed smog the last time, so I might need new cats later anyway. Yes, there are less expensive sound-enhancing options available, but I particularly like the fact that I have removed weight at the rear, not added any. And, others have reported modest power gains with these cats, which you cannot get with muffler mods.
Like so many others have said, DACH's workmanship is superb, from what I can tell. The only welding I have ever done was in a college: on a roommate's Jeep roll bars (God, I hope he never rolled) and an architecture project (foam core is for sissies!).
The fit of the DACH X-pipe was very good, though I did have to move my mufflers rearward a good 1/2". There was one very minor fitting glitch. On each side, there are two nuts attached to the factory (Bischoff) headers and one nut on the cat (poor cat). The DACH does not have said nuts. No problem, I just had to go and buy two new nuts and washers to fit the factory bolts. Naturally, my local hardware store has stainless-steel hardware and metric hardware, but no stainless-steel-metric hardware. So I got two new 5/16" bolts, washers and nuts (works with the same 13mm wrenches!). I will correct this some day.
BTW, I did not have much trouble getting the old bolts off. I put some penetrant on one that seemed to be resisting, but otherwise, they all came out fine, even after 111,000 miles, and after some quick cleaning, they seemed perfectly reusable.
I left the big heat shield in place, but I removed the bracket that supports the retaining straps, and of course the O2 sensor shield. I installed new gaskets (purchased from dealer) between the headers and cats, rather than reuse the old ones. Installation took about 3 hours, but that included jacking up the car, figuring out where all the bolts were and what sizes they were, realizing the heat shield was attached to the car, and finally realizing after struggling for a while that I had to loosen one muffler strap to get the cat out. I could probably do it again in under 2 hours.
The sound is great. I have the stock non-motorsound mufflers, and so far the combination seems to be a good one. I did not want anything too loud, or too "throaty" American-V8-ish. Too many pickups and Chrysler 300s sound like that. I have heard the Darin Fister mod (aka LPMM) in person, and it is way too loud for me. It's a great sound, but just too much sound for me.
The combination of DACH sport cats and stock mufflers has what I would call a really nice 911 snarl. It sounds like a flat 6, not like a V8 or a Ferrari, and certainly not like any hopped-up import. It is not obnoxiously loud, but you can tell there's something special going on in there. From inside the car, with the windows up, it really is very close to stock volume until you romp on it in the higher rev range. Outside (that is, what I could hear going thru tunnels), it is surprisingly loud and race-car-like when you rev it. Again, very 911-sounding, with a nice "bark" to it.
I am hoping there will be some performance improvement (freer revving is something others have mentioned, in addition to horsepower gains), but I have not had a chance to really test this aspect yet.
One thing that I don't think anyone else has mentioned, but really had me freaked out, was that the new cats gave off an unusual smell when they first got hot. It smelled kind of chemically, not quite like exhaust fumes or burning oil. I couldn't tell if it was coming from the tailpipes or thru the heating system into the cabin. I figured it was just because they were new, but then, laying in bed at night, I began to think... maybe I had cracked a header or opened up an existing crack when I torqued down the new cats, or maybe I had removed or bumped something I shouldn't have, or that there was suddenly some other problem with my heater boxes or heating system. But after another drive, the smell seems to have calmed down if not gone away altogether.
So, kudos to Chris and Dave for making such a great product. It took a while (I was last in line in the group buy - maybe they are faster if you just order one?), but it was worth the wait. Bottom line, they sound great and weigh less than the stock cats. And maybe I will notice some performance gains, we'll see.
Like so many others have said, DACH's workmanship is superb, from what I can tell. The only welding I have ever done was in a college: on a roommate's Jeep roll bars (God, I hope he never rolled) and an architecture project (foam core is for sissies!).
The fit of the DACH X-pipe was very good, though I did have to move my mufflers rearward a good 1/2". There was one very minor fitting glitch. On each side, there are two nuts attached to the factory (Bischoff) headers and one nut on the cat (poor cat). The DACH does not have said nuts. No problem, I just had to go and buy two new nuts and washers to fit the factory bolts. Naturally, my local hardware store has stainless-steel hardware and metric hardware, but no stainless-steel-metric hardware. So I got two new 5/16" bolts, washers and nuts (works with the same 13mm wrenches!). I will correct this some day.
BTW, I did not have much trouble getting the old bolts off. I put some penetrant on one that seemed to be resisting, but otherwise, they all came out fine, even after 111,000 miles, and after some quick cleaning, they seemed perfectly reusable.
I left the big heat shield in place, but I removed the bracket that supports the retaining straps, and of course the O2 sensor shield. I installed new gaskets (purchased from dealer) between the headers and cats, rather than reuse the old ones. Installation took about 3 hours, but that included jacking up the car, figuring out where all the bolts were and what sizes they were, realizing the heat shield was attached to the car, and finally realizing after struggling for a while that I had to loosen one muffler strap to get the cat out. I could probably do it again in under 2 hours.
The sound is great. I have the stock non-motorsound mufflers, and so far the combination seems to be a good one. I did not want anything too loud, or too "throaty" American-V8-ish. Too many pickups and Chrysler 300s sound like that. I have heard the Darin Fister mod (aka LPMM) in person, and it is way too loud for me. It's a great sound, but just too much sound for me.
The combination of DACH sport cats and stock mufflers has what I would call a really nice 911 snarl. It sounds like a flat 6, not like a V8 or a Ferrari, and certainly not like any hopped-up import. It is not obnoxiously loud, but you can tell there's something special going on in there. From inside the car, with the windows up, it really is very close to stock volume until you romp on it in the higher rev range. Outside (that is, what I could hear going thru tunnels), it is surprisingly loud and race-car-like when you rev it. Again, very 911-sounding, with a nice "bark" to it.
I am hoping there will be some performance improvement (freer revving is something others have mentioned, in addition to horsepower gains), but I have not had a chance to really test this aspect yet.
One thing that I don't think anyone else has mentioned, but really had me freaked out, was that the new cats gave off an unusual smell when they first got hot. It smelled kind of chemically, not quite like exhaust fumes or burning oil. I couldn't tell if it was coming from the tailpipes or thru the heating system into the cabin. I figured it was just because they were new, but then, laying in bed at night, I began to think... maybe I had cracked a header or opened up an existing crack when I torqued down the new cats, or maybe I had removed or bumped something I shouldn't have, or that there was suddenly some other problem with my heater boxes or heating system. But after another drive, the smell seems to have calmed down if not gone away altogether.
So, kudos to Chris and Dave for making such a great product. It took a while (I was last in line in the group buy - maybe they are faster if you just order one?), but it was worth the wait. Bottom line, they sound great and weigh less than the stock cats. And maybe I will notice some performance gains, we'll see.
01-26-2009, 03:22 PM
#2
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So many options for exhaust. A local RLer, Jo-Hans, has the DACH-X pipe with RSR mufflers and I love the sound. No 5L V8 Mustang sound (like my Supercups sometimes) but a nice throaty growl at low RPM and a shriek higher up. Any chance of a sound clip?
01-26-2009, 10:33 PM
#3
Race Car
hey Bruce........thanks for the kind words and of course your business Sorry for the wait 
I forgot to tell you about the bolts (later cars don't have the same issue.....ooops
) sounds like everything worked out well in the end though.
Tell a friend
Sorry for the wait I forgot to tell you about the bolts (later cars don't have the same issue.....ooops
) sounds like everything worked out well in the end though. Tell a friend
