Exhaust Question

[Andre]

Hi,

I've got an '84 2dr SBC car. It has dual exhaust on it now w/ headers that needs replacing badly.

The car isn't a hotrod and sits very low, my priorities for this exhaust system are as follows;

1. Clearance
2. Sound (No drone)
3. Efficiency

What i'm thinking is the following, could anyone offer any input or suggestions?

Shorty headers to an OEM style Y-pipe, pass the crossmember through the OEM notch Use a single in, dual out muffler tucked in the OEM location and running two pipes straight back and exiting under the bumper.

Does anyone have a similar configuration? What dimension of muffler did you use? Any advice? An obvious answer it to use an OEM system, but I'd like to increase flow a bit as there's a mild motor in the works, also a nicer tone would be a big +.

Thanks!
Andre

 

[85 Cutlass Brougham]

I have the Edelbrock TES headers and downpipe, spec'd for a MCSS as it has a larger converter than the standard model. I also used a Walker Dynomax cat back, which is a POS with a horrible Y pipe that is to be avoided like the plague. It is quiet, but I am looking at other alternatives for the cat back in the future, and think the Hooker setup looks much nicer. It is also cheaper, and uses larger tubing. Oh, don't buy a direct replacement converter if you go this route, go with a universal 3 inch instead. The direct fit models stretch a 2.5 in converter to fit the oval inlet and outlet while the 3 inch allows you some more flow if done right.

 

[Tony_SS]

Wait til you get the v8 in place and put the $ toward a good true dual system. Thats the only way you're going to see any significant improvement. I wouldn't put anything in a y-pipe/cat system.

 

[axisg]

what is you ultimate goal ? I am unsure of shorty headers + a Y-Pipe.

Why not an aftemarket set of headers ( TES is nice ) plus a cat-back system? That setup is good to breath until appx 400hp from what I understand.

What you are talking about can be done ( we used to use a 2nd gen Camaro muffler and set it up the same way as the GN ). There are a few Cat-Back systems sold today that can be bought and installed in your driveway for not a lot of $$.

 

[85 Cutlass Brougham]

I have also considered another way to solve this dillema, and that would be a dual inlet, dual outlet catalytic converter. This way, what you end up with is sort of like an X pipe, with the X being the cat. Technically, it would still be legal because it maintains a single cat in the factory location, but it would still be a true dual system. I have also considered ( I hate drone too) using a dual exhaust with a dual inlet, dual outlet cross flow muffler, like on a 2nd gen Camaro, in the factory V6 location behind the axle, with dual mufflers under the back seat. This would make for a fairly quiet system, while still allowing you to get the mufflers from a good, free flowing aftermarket company like Flowmaster. It would act like a 4 muffler system, with additional sound control coming from the catalyst or catalysts, depending on what you used. If you went to a true dual system with this, you could also run an X pipe in the middle, with one cat on the driver's side, and one on the passenger's. If you did that though, I would recommend finding another G body in the junkyard and taking it's catalytic converter heat shield. This way, you could put it on the driver's side to cut down on radiant heat coming up under your feet.. Then again, as another X pipe variant, you could also use a dual inlet/outlet muffler in the crossover position as your X joint. So, at maximum, you could have 4 mufflers and 2 cats to cut exhaust noise, or 3 mufflers, an X pipe and 2 cats to cut noise. As you can see, I have thought at great length about this as it is a subject I intend to tackle once my car is painted and assembled. I want free flow, just not the cop baiting noise.

Oh, one more thing that would be cool is what is called an active muffler. It basically has no baffles or restriciton inside, but uses electronic noise cancellation technology. Essentially, it uses a speaker to emit sound frequencies to cancel out the noise of the engine. I have no idea where you can get one, but I remember seeing it on The Discovery Channel on Beyond 2000 in the early 90's when I was in High School.

 

[Tony_SS]

Actually, I was doing some research on the subject myself, I ran across a video of 85 Cutlass working on his exhaust solution:

http://youtube.com/watch?v=wAn8rgrcGRU

:lol: :lol:

As you can see, if 2 mufflers are good, 5 mufflers are better, and, well HVAC ducts are great!