Well... In short, all the VRIS does is add power. It utilizes what it already has, and builds more with that. If you need a true explanation, well...
http://www.mx6.com/forums/2g-faq-general/162593-faq-what-vris-everything-you-wanted-know-more.html
But, if you're wondering if it's necessary, no it's not. All it is for is a better power curve. If you don't have it, your car will still run fine, just won't have the power you may be used to...
http://www.mx6.com/forums/2g-faq-general/162593-faq-what-vris-everything-you-wanted-know-more.html
But, if you're wondering if it's necessary, no it's not. All it is for is a better power curve. If you don't have it, your car will still run fine, just won't have the power you may be used to...