stock tubing isn't smooth 100% of the tube on the inside...that's the only difference..honestly doesn't make a bit of difference on a stock sixxerHow does the PVC tube differ from the rubber hose we have on our intakes? Haha never heard of this before
Why? Whats the difference just get two silicone couplings and put them on the endsNo i need a 90 silicone cuppling