It depends on how fast your going and where you put the tape for it to help. I tried lots of things myself and watched and learned from others. Remove the side mirrors completely if possible. I didn't do it but a Mustang did and gained almost 2mph. The last 1/2 mile I ran had technical problems i.e. no official times. I closed off the grill with collision wrap and saw 145 on the speedo. Water temps stayed normal as well as IAT's with just the lower grill open. Taping all the seams on the hood, removing the windshield wipers, removing the passenger seat etc. made no measurable difference. Hope this helps.