“Straight piping” your exhaust is a religion. It came from the Israelites on the seventh coming of the Lord’s name, which they proclaimed: “Thou shalt remove all restrictions from thy exhaust system, and thus spit fire, and make more burning bushes, bro.”
A little later, the Philistines rationed horse-drawn carriages laxatives, which made it easier for them to clear out those pesky organic exhaust pipes.
This produced a lot of methane gas and pollutants, but made those horses move at record paces. A few thousand years later, Henry Ford dropped the Model T on the American people, and people began modifying the exhaust.
It appears as though it was due to the novelty of the sound you could create with it, rather than any semblance of performance gains.
What is a Straight Pipe Exhaust?
A straight pipe is normally thought of as a straight pipe that goes from your engine out the back of your car, truck, or motorcycle.
A straight pipe bypasses the catalytic converter, the emissions controls, and shoots a ton of sound towards the people you don’t like when they tailgate you. Sometimes, if you were running rich enough, you could even shoot flames out the back.
That’s what a straight pipe exhaust is for: it’s for fun, and it’s cool to hear your engine better!
Straight Pipe Advantages
A straight pipe can give you horsepower and top speed, and if you have some form of turbo, more power and top speed, because you can remove all restrictions through the exhaust system, allowing your engine to run so much better.
However, in a street vehicle, you might see a reduction in HP and torque under 2500 RPM, as your street vehicle was designed to have back pressure in the system, and tuned to specification and performance based on back pressure.
A straight pipe can also warn other motorists of your inevitable approach when you drive up behind them or sit next to them at a stoplight.
Straight Pipe Disadvantages
One downside could be that your car may make less horsepower at lower RPMs as you remove some back pressure by straight piping your ride.
A second downside could be that you won’t be able to pass emissions and register your car with an exhaust system that is expelling more CO2 than when it left the factory.
A smeller downside is when you straight pipe your exhaust system, you are going to shoot unburned fuel and gases out the back of your car, causing you to smell it from inside the cockpit.
It would be worth mentioning that everyone behind you gets to smell all that if they have the windows down, which also kind of sucks. So, if you care about that in any way, I would not recommend straight piping your car. One alternative to straight piping your car is a cat-back system.
In my experience, the sound was probably the hardest part of straight piping. Yes, you will have a sound you have never experienced with your car before, and yes, it really is a unique sound. But if you have to drive that car to and from work every day, it gets annoying real quick.
When looking for exhaust kits, buy once, cry once. Get a system that has been made better with an actual acoustic engine, so you aren’t stuck with a “drony” system that will make you crazy.
Are Straight Pipe Exhausts Legal?
Straight piping is illegal in most cases that I have found, but legality varies by state.
Most states have some version of laws like these, and it would probably be in your best interest to pay attention to them. However, most people do not get pulled over for straight piping exhaust, unless they are still home, your car is obnoxiously loud, and their sleeping neighbor shows up.
On a side note: NOBODY likes the guy who cold starts his straight pipe Jeep Grand Cherokee Track Hawk at 6 am to go to work. Nobody.
Is Straight Piping Bad for Your Car?
Depends on the engine. For some engines, relieving resistance causes the motor to run rich and out of tune.
Plus, you’d want to get a tune done if you changed something like your exhaust system for optimal fuel burns, and possibly see your miles per gallon improve.
How Much Does a Straight Pipe Exhaust Cost?
Like most of the mods, it depends on how much money you want to spend.
You can always just go to the muffler shop, hand him a hundred dollars, and he can make you a straight pipe exhaust from spare parts.
When I see this scenario, I cringe because it isn’t going to sound that great, and you’ll get a raspy sound that is ear-splitting and high-pitched when at full throttle.
That ear-splitting, high-pitched exhaust sound you normally hear from a Honda CRX at a car meetup is more on the “raspy” side of sound, not my taste, but whatever.
If you want a professionally engineered and manufactured straight pipe exhaust kit, or a race pipe (deleting your catalytic converter and replacing just that section), you’d most likely spend $300-$450 on parts alone, then pay $200+/- for labor to install.
If you want the least drone, least resistance, top-of-the-tier straight pipe kit, go with HKS. They are true legends in the business, not sponsors as of now. With that being said, it could cost around $500-$650 just for the parts.
Along those lines, I’d factor in $350 for when you eventually have to put your catalytic converter in because the straight pipe is obnoxiously annoying, trust me, I have been there too. (Check out our article on the Check Engine Light.)
Where Can I Get My Car Straight Piped?
If you’re looking to straight pipe your car, you’ll want to find a shop that is able and willing to perform exhaust modifications.
Visit a Cars n Coffee event nearby, drag strip, or race track. Ask around and someone will probably give you a recommendation. If not, here are some options:
Performance Tuner Shop
Take your car to a performance shop that specializes in modifications and tuning for your make and model of car. They will usually have experience engineering and installing straight pipes to match your engine. A performance shop usually will have custom labor and sound tuning.
This route usually yields the best results, but will likely cost you more in labor.
Your Trusty Muffler Shop
Your local muffler repair shop may have the willingness and know-how to straight pipe your exhaust system. They will have all the pipe-bending tools, welding tools, and fabrication skills to do the job.
Because of the legality issue of straight piping in various regions, many shops (especially chains) won’t do it. Your best bet is a mom-and-pop, independent shop. Bonus points if it’s owned by a car enthusiast.
Do It Yourself with a Kit
If you are savvy with tools and have a place to perform the install, you can save on labor. Order a universal straight pipe or race muffler exhaust kit from an aftermarket supplier like Magnaflow.
Pair it with an O2 sensor spacer. Then either do it yourself if you have the tools, skills, and a place, or pay the exhaust shop for just installation time versus custom fabrication.
Straight Pipe vs Cat-Back
Now the question most madders start out asking themselves in their journey: “Should I go straight pipe or cat-back?”
In short, cat-back exhaust systems are everything in your exhaust system after the catalytic converter.
That’s why it’s called a “Cat-back” exhaust system. Typically, it will be cheaper than doing a full exhaust system, and it usually will not bypass the oxygen sensor on most cars, which are typically mounted on or by the catalytic converter.
As you are not bypassing anything that matters, your exhaust is not emitting as many harmful gases into the atmosphere, and you won’t have the headache of the emissions testing center making you go pay for them to fix your car.
Moreover, it is completely subjective, but the sound of a cat-back exhaust, when done right, is more muted, quieter, and therefore easier to live with. You won’t wake your neighbors when you start your car, and you will be able to hear your girlfriend talk to you in the passenger seat when cruising on the highway.
Alternatively, if you just want to “full racecar”, straight pipe that thing and “shoot flames” out the exhaust.