Hole in vehicle exhaust

[edprush]

What do you think would be the outcome of a hole in a car's exhaust? Would the mileage be better or worse than if the exhaust didn't have a leak?

 

[Howard]

Where is it?

 

[nineball9]

You'll save on gas if you can't drive your car, namely if it fails inspection.

 

[edprush]

Originally posted by: nineball9
You'll save on gas if you can't drive your car, namely if it fails inspection.

they don't have inspections in my state.

 

[edprush]

Originally posted by: Howard
Where is it?

between the manifold and the muffler.

 

[alkemyst]

i think all exhausts have at least one hole in them....if it couldn't get out you wouldn't make much power.

Anyway exhaust leaks are bad...a few small holes would not make a significant difference in mileage improvement.

Car/truck exhaust designs are based a lot on keeping the gases from entering the cabin. While rear exiting dual exhaust seem popular, there are many reasons manufacturers don't have them on vehicles with flat backs like Ford Broncos.

 

[AgaBoogaBoo]

i think all exhausts have at least one hole in them....if it couldn't get out you wouldn't make much power.

😀

 

[Zim Hosein]

Originally posted by: AgaBoogaBoo
i think all exhausts have at least one hole in them....if it couldn't get out you wouldn't make much power.

😀

Haha! 😀

Cheers AgaBoogaBoo :beer:

Originally posted by: edprush

What do you think would be the outcome of a hole in a car's exhaust? Would the mileage be better or worse than if the exhaust didn't have a leak?

IMO, worse as you need a smooth flow of the exhaust gas through the tailpipe and a hole in the system will disrupt the flow.

 

[Black88GTA]

Originally posted by: edprush

Originally posted by: Howard
Where is it?

between the manifold and the muffler.

lol...well, that certainly narrows it down... 😛

A small leak won't really affect mileage, unless it occurs before an o2 sensor. This would cause the o2 sensor to give wacky readings and erroneously adjust the fuel mixture. The greater danger (as alkemyst said above) is exhaust gases escaping under the car and entering the cabin.

 

[Alone]

They're built without random holes in them for a reason.

 

[Eli]

It depends on where it is. If it is anywhere before the muffler, it will certainly not help MPG. If the leak is bad, it could actually lower MPG.

If it is in the muffler.. it probably won't increase MPG, but it shouldn't negatively effect it, either.

 

[Aikouka]

Wouldn't it raise performance though if the hole were before the catty? Not talking huge numbers, but numbers none-the-less. Mainly going on the idea that some exhausts tend to deprive the engine of "power."

 

[Eli]

Originally posted by: Aikouka
Wouldn't it raise performance though if the hole were before the catty? Not talking huge numbers, but numbers none-the-less. Mainly going on the idea that some exhausts tend to deprive the engine of "power."

An exhaust leak is almost aways detrimental to engine performance. It disrupts the flow of exhaust through the tube, reducing performance.

Imagine the engine is a sound generator, and imagine the exhaust pulse as a sound wave front... That's actually exactly what it is.

As the wave front travels through the exhaust pipe, it leaves low pressure in its wake. This has the effect of continuing to pull exhaust gases out of the cylinder, called scavenging.

If you have an exhaust leak, the wave front is disrupted, as is any low pressure area that the wave does create. This reduces overall exhaust system performance and scavenging, which has the net result of lower engine performance.

Now.. If you were to put straight headers on your car, eliminating the muffler, yes.. you would see a potentially large increase in top end power.

Notice I say top end. You would most likely not see an increase in low end power with such a setup, because exhaust systems rely on a certain amount of backpressure. This gives the exhaust pulses a more dense medium to travel through, and actually increases scavenging effects.