How to Tune Your 4×4 with the Right Modifications
Tuning your 4×4 or truck with the right outback exhaust mods can be very tricky. If everything is set up correctly, then torque, mileage and horsepower go up because the engine will be working more efficiently and easily. It’s a simple recipe for success with lots of science behind it. You want unrestricted, straight-flowing exhaust without too small or too big pipes. If the pipes are small, the exhaust flow is going to be restricted. If they’re too big on the other hand, the exhaust will just tumble on the inside of the tubes and you still won’t get a proper exhaust flow. Here are a few things to be on the lookout for when shopping for an outback exhaust.
First off, the cast-iron exhaust manifolds are heavy, big and restrictive. If you ditch them for a set of headers from an aftermarket brand, this will free up a lot of power and it will reduce engine heat below the hood, since the headers hold the heat in the exhaust far better than the radiating stock manifolds. This is the first part of your system, so if it’s restrictive, what’s the point of having other exhaust work done? When you add a set of headers, you can easily run into several issues.
For example, the headers can be bolted onto a 440ci engine, but they wouldn’t fit between the framerails without lifting the engine a few inches off the engine mounts first. Things like this need to be thought through before rushing off and buying something, else you’ll be stuck paying twice as much for parts and spend twice the time to get what you had in mind.
Additionally, consider getting a high-flow catalytic converter for your 4×4 or truck. They do a lot of emission reduction, and you’re not doing yourself a favor by pulling them off because it’s you who is around your vehicle most of the time, breathing the exhaust gasses. Nowadays, there are even high-flow catalytic converters for diesel trucks. The power loss from having a catalytic converter is so small that you’d be surprised if it registers even more than 1 horsepower. Bottom line is, keep your cat!
Adding a whole new exhaust system is the way to go, otherwise what you’d be really doing is moving the most restrictive part to another area of your exhaust, if you’re only adding a part here and there. Not only will replacing the whole exhaust system give you the optimum performance, but it will also be compatible and it will come together as a package, which will keep the overall cost down compared to buying things separately.
