Running Straightpipes, will It Cause Damage??

[solaris=amazing]

I got a 95 ford thunderbird 4.6 V8 w/dual exhaust. Now i want to chop off the mufflers, and run straightpipes-directly from where the muff's where chopped off, KEEPING the cats. Will this cause any damage?? I want the car to be alittle louder, and i did read that it gives you more passing power-is that true?? I would guess that having the muffler off, the air could get out fast, causing "slight" increases in acceleration.

BTW, all exhaust lines are clean, no rot. The exhaust now is completely stock.

[psychorallyfreak]

The only damage it would cause, would be to your wallet, when the noise police pull you over.
No mufflers=less back pressure=more power
but it also means less torque...

[solaris=amazing]

Yeah i wonder if the torque would be hurt that that much. I read that at higher speeds, like over 50mph, it gives slightly more power-but the torque is hurt slightly. Will it be that loud?? Also, i believe it would not be to bad as to say i'd get tickets. If they wanna f*** with you, then yeah. The chrome pipes i got is literally a perfect fit also, this would look real good. I just got my car back from the bodyshop, had the whole baby repainted silver frost.

[Rufe]

In your specific case, I can't see any damage being done. Except to your wallet when you get a noise ticket.

You may get an extra 3-8 hp. (guessing)

However, for the sake of arguement, the exhaust manifold, cat and the small diameter of the stock exhaust tubing will still give you backpressure. Running a completely open exhaust, independent on both sides, would be an entirely different situation. And deserve a different answer.

I suggest you listen to an unmuffled car before you go cutting off the mufflers. Especially if you like clarity in your music. You may also find a certain muffler that gives you a better sound. If you want more power, the best bet is to look at TOTAL flow through your exhaust system, match the exhaust tubing and muffler to your particular engine. Stock I am guessing? Certain engines respond to certain mods like crossover pipes, and tube diameters.

And, Is it a true dual exhaust, or a 2 into 1 into 2 exhaust?

[MagicRat]

Originally Posted by Rufe

In your specific case, I can't see any damage being done. Except to your wallet when you get a noise ticket.

You may get an extra 3-8 hp. (guessing)

However, for the sake of arguement, the exhaust manifold, cat and the small diameter of the stock exhaust tubing will still give you backpressure. Running a completely open exhaust, independent on both sides, would be an entirely different situation. And deserve a different answer.

I suggest you listen to an unmuffled car before you go cutting off the mufflers. Especially if you like clarity in your music. You may also find a certain muffler that gives you a better sound. If you want more power, the best bet is to look at TOTAL flow through your exhaust system, match the exhaust tubing and muffler to your particular engine. Stock I am guessing? Certain engines respond to certain mods like crossover pipes, and tube diameters.

And, Is it a true dual exhaust, or a 2 into 1 into 2 exhaust?

Very good explaination. Different exhaust systems will respond differently to muffler removal and other tuning efforts. There are many factors that affect noise and power production, such as flow dynamics and engine design.
Rather than use trial and error, consider purchasing an entire system, where all the engineering has already been done for you.

[SaabJohan]

Lower exhaust pressure means higher torque and higher power, exhaust pressure is always a bad thing.

However, most exhaust backpressure is probably caused by the parts of the exhaust system closer to the engine.

With a NA engine the exhaust manifold have a large effect on the torque and powercurve of the engine. This since the scavenge effect depends on the velocity in it. So with a larger system the speed decreased which usually decrease torque at low speeds but increase it a high speeds because of the reduced backpressure, while at the low speeds it didn't reach the velocity needed for the scavenge.

[NiN52445]

I plan on straight piping my exhaust soon, too. I just want a really loud sound, though. I'll probly get an 80's series muffler in time.

[MagicRat]

Originally Posted by NiN52445

I plan on straight piping my exhaust soon, too. I just want a really loud sound, .

People with really loud exhausts are a real pain in the ass, and spoil things for the rest of us. If you do this, I hope you get the ticket you deserve.

[NiN52445]

Thats funny, because around here people don't really care that much. I ran my car without a muffler for 4 months last year, and I didn't get a single ticket. But I somewhat agree, straight piping is a little over the top, which is why I am going to get a flowmaster shortly after discarding of my current muffler.

[SaabJohan]

When you keep the catalysts they will act as a muffler so the car won't be that loud, it's the same with a turbocharged car but there the turbocharger acts as a muffler.