Choosing the Right Headers
You can set your head spinning trying to decide on an exhaust system for your car. Rather than add to the problem, we thought it best to compile a short informative article on this exhaustive subject.
The entire premise behind an aftermarket exhaust system is to allow for enhanced evacuation of exhaust gases. If these gases remain in the combustion chamber, they will be taking up space better used by fresh air and fuel. This in turn robs your motor of potential power and torque (this is a bad thing). First, you need to answer a question; what kind of driving will you be doing in the car? Dedicated drag racing machines or circle track cars will need more power at higher RPM’s, whereas street driven cars will benefit more from a broad power curve with low-end response for city driving and such.
Size - it only matters a bit here. Don’t go out and buy a 3 inch header for your 350, which is what is commonly considered overkill. Not only that, it can actually rob your engine of more power. Most of our techs agree that a street application 350 will benefit well from a header with 1 1/2” to 1 5/8” diameter. What this size does is creates a faster removal of spent gas and also develops just enough backpressure for a broad torque response.
There are a few different styles of header lengths out there today, and here are the two most common; “shorty” and "full-length".
“Shorty” headers usually work best in limited space engine bays, as well as lowered cars. They will also usually work well with your factory exhaust system, should you choose to keep it. You can get the most for your time and money by buying a set with equal length primaries. These will scavenge gas from each of your cylinders equally, meaning your power is consistent and your torque curve broader in the low to mid-range spectrum.
Full-length headers are the most recognizable header setup, usually consisting of long primaries tubes converging into a 4-1 style collector. The long primary tubes reduce the chance that you will have back-feed of gases into a different tube. These headers help to produce the most overall power with a broad spread through the low- to mid-rpm ranges.
Aftermarket headers are usually made from either mild steel or stainless steel. The major difference between the two is cost. The basic steel headers will be quite a bit less in cost, however they will sacrifice durability and longevity. One option you could pursue is a ceramic coating, which will add a thermal barrier. This will reduce the under-hood temperatures more. For a bit more information on Speedway’s own ceramic coating, click here. Included below is a chart showing the dimensions commonly used for header measurement when checking for fitment. Speedway lists these dimension on each product page, and you can narrow your Search results by them as well.
