is there a difference in the angular position of the cat flange on INTEGRA NONVTEC and VTEC header? the header i bought is a dc 4-1 for an LS, and when the header is bolted to the car the flange is at a 0 degree angle (completely horizontal) but some headers that i see are at like a 30 or 40 degree angle on the flange. is this the difference between vtec and nonvtec headers?