I know this will be a comment that some will despise, but its really hard to kill those old Hondas. My sister had a 1987 Accord that is probably still running, but the body was just decaying around the engine...especially in the wheel wells. You could hide watermelons in the rust holes.

it got louder when the exhaust fell off, but once all the piping went, it sounded like a ricer, lost unbelievable amounts of power, and wasn't enjoyable to drive due to the noise level.

no back pressure in the exhaust

FYI 

The exhaust system should have minimal restriction to the exhaust flow that is being released in order to create the most amount of power from the engine. With restriction present, backpressure is developed, making the engine work much harder to release the exhaust out of the engine cylinders.

The standard for exhaust diameter is to not run too large of exhaust, for the engine needs a certain amount of backpressure. This is correct in the sense of one should not run too large of diameter exhaust tubing, but the statement of the engine needing backpressure is not. You need to have the least amount of backpressure possible to produce maximum power. Too large of diameter exhaust will cause a power loss (or no exhaust at all) and loss of low end torque because a larger pipe has less exhaust stream velocity than a smaller pipe. If the exhaust pipe is too large, then the exhaust flow will be slowed with less velocity. There are exceptions, forced induction or high-volume race engines require a larger diameter exhaust due to the flow characteristics of the engine. Supercharged and turbocharged vehicles can have an exhaust gas volume of 1 to 2 times more than an equivalent displacement naturally aspirated engine. In this case, one is able to use a larger diameter of exhaust for greater performance.

Below is a general rule of thumb when selecting a diameter for your exhaust:

• 100ci - 150ci motors = 2 inch exhaust tubing

• 150ci - 220ci motors- 2.25 inch exhaust tubing

• 220ci - 350ci motors- 2.5 inch exhaust tubing

For supercharged and turbocharged vehicles, one should use no less than a 2.5 inch exhaust system. Forced induction vehicles with a 220ci or larger engines can use 3 inch exhaust.


So remember, when purchasing your new exhaust, that a performance exhaust from a reputable aftermarket company is important. You want to select an exhaust system that has been tested and tuned for your application. And, keep in mind what the type of modifications you have and what you plan to do in the future. This will allow you to make the correct choice in choosing your next exhaust system.

FMI,  I would believe you, but...I still have questions. first....I dont think it is the velocity of the exhaust going out, but the amount of exhaust going out that spins the wheels...or is it the exhaust that powers the wheels, if so, then there would be extremely low back pressure at the low end...not much more at the high end either. making an engine work harder..doesnt that wear on your engine? also, if what you say is true, then current engines suck at efficiency. I understand the whole idea of producing a certain amount of power at a certain revolutionary speed. But why would the same graphical curve apply to that of which should be linear? that is, the ratio of exhaust leaving should be the equivalent of the power which it is supplied. put simpler, I would like to see dyno results of having too wide of an exhaust and too small of an exhaust. I would like to quantify these results and graph them. This seems like something in the autoworld that could be improved upon. could this also be the issue where some cars have more high end or low end power? If so...I just might squeeze mine up....cuz if your theory is correct, theoretically, I should have more low end torque due to the increase in velocity over a short period of time within the exhaust piping. This would mean that turbos, would spin faster, providing more air and quicker throttle response, and would have the ability to be more powerful. but then is it only the velocity of the exhaust? or the force which it creates. Being that the engine doesnt slow down due to the smaller exhaust...there actually is more power since the passage acts as a surface area reduction with the same power over a smaller area. so..turbos would actually provide more power if connected in parallel across multiple exhaust pathways thus eliminating Lag and creating a super turbo....just my too sense.

well put. 

well this was on the Accord that dropped all the piping, not the Mazda. But I never had a chance to test the Accord on the highway. All city driving.

More funniness to add. We were going to go to Midas to get the exhaust replaced when this happened.