Yep, Dynomax SS Ultraflow is the name of my favourite muffler:

http://www.dynomax.com/mufflers.stm

 

Pete, you brought up an excellent point. I just cut and pasted something from their web site. I don't even bother to think about claims made by companies. I know what I want an don't really care what people say the gains are. Most of the time they are fixed anyway. If you simply ignore the actual #'s the claims make some sence and the clip is informative.

I am in no way endorsing Dr. Gas products nor do I even accept the claims made on the web site. I just thought the explanation was decent, and I was too lazy to type my laymans explanation.

I live in Orlando (right next to Datoyna). I used to race the IMSA and SCCA circuits, and know several people involved in NASCAR. Dr. Gas is great place for NASCAR exhaust parts. They do meet spec requirements for the rules. And I know people who use their products and are very pleased. The quality is very top notch and their products have proven to be successful in extreme racing conditions. So if they can stand up to the grueling Rolex 24 Hrs. of Daytona as well as the Daytona 500, its good enough for my SC!

Am I paying more for the exact same part - maybe, but mentally its worth it for me. Like Pete said: Is one better than another? Who knows, and for our purposes, who cares. The differences between brands most likely won't be noticible for our cars anyway. All can agree that an x-pipe has benifits. Buy what every you like or can afford. Personally I like the mandrel bends of the Dr. Gas x-pipe rather than a stamped unit, so I don't mind paying a little more for it. Plus they will make it you your custom specs which is exactly what I need since I will be installing it myself w/o a tube bender and have to connect it to headers that are not in stock locations.


Keith

 

The US spec sc4 exhaust isn't going to hold back any great amount of hidden hp,maybe some rumbling sounds,but that's it.
Unless of course you have some substantial cams or something.

Off topic here;Peter,do happen to recall what the factory cam timing is on these motors from your recent tuning in that dept.?

 

I agree with Keith and SCV8.
Biggest ever improvement I have ever seen on any SC (jdm) is roughly 20 hp at the wheels. That's headers, x-pipe, 2.5 inch and straight through mufflers.
Not a lot - you will notice it.


Standard exhaust cam is 46 BBDC and 3 ATDC 229 duration
My hardfaced exhaust cams are 55 degrees BBDC (Before Bottom Dead Centre) and closing of 18 ATDC (After Top Dead Centre), duration 253
standard intake is 6 BTDC 46ABDC 232 degrees duration

 

Thanks for the cam #s,do you plan to make any changes to the intake cams?
I'll bet those headers really help out to flatten,and smooth out the power curve,something the dyno may not necessarilly show.

 

So, What should I do to get the most Power out of my SC? I wanna know because I wanna do things right the 1st time (which hasn't happened for me so far) So to save time and money I wanna know what I should to and get to get the best power out of my SC400. I don't mind spending the money but I want it to be worth something in the long run.

Back to the last post : Will upgrading my entire exhaust (headers and all) REALLY BE WORTH IT TO ME? If not please point me in the right direction as to where to start

 

Most power? Bore and stroke, port and polish, torque convertor, LSD, headers and exhaust, intake, nitrous, then ECU tuning .