Contour Enthusiasts Group Archives Forums Modifications Duratec Performance BTR Exhaust Rev. 4.0

(from the list)

I think I've finally found an exhaust setup I like.

Like the dual sidepipes I just did, this one is a seperate 2" pipe off of each manifold. However, this setup goes straight back under the gas tank. Each pipe goes to a mini dynomax super turbo mounted on each side of the spare tire well. There's no crossover or balance tube at all on this setup.

Unlike other dual systems out there - this one only has a slight crush bend for each pipe to angle back up at the gas tank, and the passenger side has a pair of mandrel bent 45's on it. Everything else is straight pipe.

Ground clearance is not bad at all - about the same as my neighbor's stock S2000. I've gone over several speed bumps without a hint of scraping. (For that matter - I used to drive a 79 t/a that had less exhaust ground clearance than this, as I found out on
a rough rail road crossing once. Ouch.)

Power level is good and sound dampening is quieter than I've had since first bolting on the garbage pacesetter catback last summer.
I'm actually amazed at how quiet it is.

Here's the cool part. The sound coming out of this setup at full honk has a very nice quality to it - I've certainly never heard a
duratec sound like this. I'll try to get some sound clips, but those never seem to do real life justice. Those folks planning to attend the tail of the dragon run in October will get to hear it tho. Maybe someone there can get a good clip using a video camera or
something.

Oh, and one other thing - I've had to yank the superchip to get best power from this setup. It seems I'm now flowing more air than the superchip profile is set up for. Car was lots weaker at WOT with the chip in. Guess I'll have to go for a custom tuning setup now.

Here's a pic from the front:


And here's the rear:


Hope some of you find this useful or entertaining,
Dan Beggs
99 Cougar V6, more neighbor-friendly now

I cringe at the thought of speed bumps!

GET A X-OVER!!!

Do this:

1) With the car cold, rub some red crayon along the bottom of the pipes after the old "Y" split about a foot or two back.

2) Start the car and run it around 3k RPM's.

3) With someone watching the pipes, have them notice where the crayone starts to melt first. They should see distinct pulse points. Using a punch or awl, scratch where they are.

4) On both pipes, locate two marks that are relatively close together. Make a crossover pipe at those locations. It can be an H, but if you can make an X-pipe, that would be better.

That should make your sound even better.
Get on it man!!!

I will be copying Blorton's dual set up as best I can this weekend using mandrel bends and an x-pipe. Sick of hearing that SMA fart coming from Silvie's rear end... and that drone, OIYOYOI ! Will post results and pics if I can while doing the BNM website cleaning this weekend as well. Wish me luck!

Hey Dan, what happened to your main cat?

Seriously, it looks really nice man!

No heat shield = BOOOM! I don't know about that...good luck is all I can say.

Chris,

Thanks for the info on the crossover pipe. However, you seem to indicate that sound would be the primary benefit to this. Uhhh, I know that's what you really meant is it?

Not sure if I'll try doing a crossover pipe - I'm happy with how it performs as is. Plus, as I've said before, a poorly placed crossover or x is worse than none at all. :p

No heat shield? Who said I didn't have a heat shield?

dan

Using the Crayon method will insure the X or H is placed correctly, for best performance and sound. Let me emphasize that running a V6 with two seperate exhaust paths is much less effecient that with a crossover. They need to balance out.

I appreciate your position Chris, but my point is that even without a crossover of any type, I'm still making more power than a y-piped setup.

Check out this tidbit from a smart guy on shotimes that first did something like this on his sho 10 years ago:

"The optimum crossover point for a balance tube as someone already mentioned will be at a different location on each pipe. The length of the tube to meet these ponts will cause further complications. I specified roughly where the tube worked best for me, but there will inevitably be variation. You may not even want a balance tube. Again, the Y-pipe is neither 'tuned' or 'balanced'. I mean, the Y-pipe is a very nice piece of hardware, but you can't tune it any better than you can tune a crossover tube for precisely the same reasons (i.e. unequal head pipe length). Let's not get confused here. "

The entire article is here:

Ted Breaux - "True dual exhausts explained"

I'll try the crayon trick, but am not sure what results I'll get since the front pipes are stainless and the rest of the system is aluminized.

Yes, I know I'd get more power with a properly placed crossover - but I'm happy with how it is at the moment and plan to leave it alone for awhile.

dan