Here is the mighty V8 Interceptor as seen in Mad Max: Fury Road. Light spoilers for those who haven't seen the film
Max's Interceptor is wrecked and captured at the beginning of the film by Immortan Joe's war boys. The war boys (who worship the V8 engine) rebuild the Interceptor. They add a dual roots-style supercharger setup, lifted rear with high-profile offroad tires, and a harpoon gun in the rear.
In the film, the war boys don't have any time to paint the Interceptor after repairing the bodywork, so the mighty V8 must blaze ahead in bare sheet metal.
It's never explained, but I believe those white tanks hold pressurized, compressed air to power the harpoon cannon.