Hona Accord performance question

[mattaoow166]

I have a 2002 honda accord se. ever since i had the cat and the stock muffler put back on it lost alot of power. i was wondering if it would be worth it to buy a 200 catalytic converter, and a new racing muffler. I dont know if that would boost the power enough for the money. any feedback would be great, thanks.

[00accord44]

your accord isnt gona gain much in the way of power with just a free flow cat-back exhaust. You'll actually feel less power lower in gears with a little gain at the top. So if you want the look and the sound go for it but dont expect to feel much power gains.

Here's some meat to chew on:

Originally Posted by jeffcoslacker

Cars are engineered for four things;

Performance
Reliability
Driveability+Comfort
Fuel Economy+Emissions Compliance

Every car is a compromise of a mix of these aspects, aimed at what they think the buyer wants. In general when you enhance one aspect, something else has to come up short. So if there way a proven way to enhance performance AND increase fuel economy, they'd already be doing it. With a few slight exceptions.

Any car's engine is basically nothing more than a volumetric pump. The goal of performance is to allow more air (and a correspondingly correct ratio of fuel) to be moved into and out of the engine in the same amount of time, which gives you stronger performance. Any attempt to "open up" a motor and let it breathe requires a similar increase in fuel delivery to have any performance gain.

This is what your engine management system's job is...to sense the amount of air entering the motor, calculate and deliver the correct amount of fuel to match it, and adjust for emissions compliance. Since the goal of compliance is the least amount of combustion by-products possible, a complete burn (and thus the most efficient and powerful combustion possible) satisfies all three requirements, performance, fuel economy, and emissions compliance.

But if you open one end and not another, like intake and not exhaust, or vice-versa, you just create an imbalance in volumetric efficiency that at best does nothing, at worst can hurt performance. But with increased and balanced flow, increased fuel delivery is going to occur as well. If it didn't, you would simply have an overly lean mixture (too much air), which burns too fast, too hot, and can damage the motor. You'd be hard pressed to increase airflow beyond the motor's stock fuel delivery capability with external mods, however, so you don't need to worry about that...

There are a couple of small ways that stock performance AND fuel economy may be improved (slightly), by eliminating the slight bottlenecks at the front and back sides, namely the air filter and the muffler. Both are designed to maintain noise levels with some small amount of performance compromised to decrease cabin noise levels. Most people don't wanna hear the intake "boom" and exhaust rumble when they hit the gas...they just want a quiet, unassuming car.

Without knowing what you actually are willing to tolerate, I'd say your best bang for the buck would simply be a drop-in K+N O.E. style panel filter (about $40) and a less restrictive muffler. This rids you of some of the concessions made for noise levels, but not in a way that will be overly obnoxious. What you will notice is more intake growl on hard throttle applications, and a more noticable exhaust note. Usually the most irritating aspect is the "drone" that 4 cylinders produce at cruising speeds, due to the 180 degree firing intervals. A cheap muffler will make a lot of this, a higher end one "tunes" the exhaust note to a higher frequency, which is much less annoying (inside the car anyway).

Since this combo really makes no apprieciable difference at lower rpm ranges, it should not create a need for increased fuel delivery during normal driving, and may actually allow for lighter throttle application to be needed for moderate acceleration...which can equal a slight mileage increase. At higher RPM ranges it will flow a bit better, which decreases the feeling of the engine's power "falling off" before reaching redline...most engines' power curves turn downward quickly after peaking aound 85% or so of it's accepted safe RPM range...flattening out the curve a bit and raising the RPM where it begins to "hit the wall" will help WOT performance...not a gain you will notice much, unless you are bumping the limiter and barking the tires on every shift

I wouldn't go with larger than stock pipe diameter unless you are going to serious beef the motor to need it...doing so will just decrease backpressure and hurt throttle response and torque down in the bottom....overly large exhaust is probably the biggest misguided performance blunder done to most cars today...most don't have the mods to require it. To actually need it, you'd have to have a corresponding increase on the front (CAI, larger MAF and throttle body, ported intake, fuel delivery mods, maybe bumpier cam, etc)...90% of the cars you see driving around with 3" pipe and trashcan mufflers have none of this...

[mattaoow166]

i appreciate the input. so what are some little things i can do to increase performance because i dont have hundreds of thousands of dollars to completely "mod out" my car.

[00accord44]

Well an intake is always a nice place to start. You don't need to shell out big bucks for a brand name on an intake since they're all essentially the same. A pipe is a pipe, just get a good filter. Good sound, lil more power, and better gas mileage.

After that, I can non longer reccommend off-brand products. The reliability of el cheapo aftermarket parts is pretty low across the board. Sorry but performance comes from the pocket first and with such a slow base, achieving any substantial performance gains will run at least $500 and really you won't get very far with that. There are many products that claim to increase hp with miracle technologies, but they're usualy lies and you get what you pay for.

Take a look here to get an idea of whats out there for you.

[mattaoow166]

alright sounds good. thanks for the response and advice, the website is also very helpful. I appreciate it