SR20 Header Project Part 1
In part 1 of this video series we take a look at the SR20 that we are designing the headers for and work out the maths involved to get the results we require from this engine, if you would like more information on header design and fabrication we have a dedicated course on this subject, check it out here.
A small capacity engine using short diff gears will need a peaky power band high up in the rev range, most of your off the shelf headers wont cater for this and after we work out the maths its easy to see.
As an exercise I want you to work out your ideal header, first you will need the tube diameter for the header, work out your single cylinder displacement in cubic inches, multiply that by your intended rpm, divide it by 88,200 to get the primary tube area in inches. To find the inside diameter take the square root of your tube area and times it by 1.273, that figure is your inside diameter for your primary tubes.
This will give you an idea for the diameter of tubes you need to use on your project and as you will see in the video we can also workout the tube lengths in relation to the camshafts used.