Well, after starting with Mr. Dremel 2 years (and another house purchase) ago, I finally installed the radiused TBI. It isn't as pretty as many I've seen here but it sure seemed to make a difference in the top end. After the TPI CAI, I noticed an increase in top end RPM to about 3400- 3500. The car felt better yet after the USED 3" catback went on. Now, the car is still pulling at 4000 RPM when it shifts. I know the tachs are notorious for being inaccurate so I was wondering what others have noticed with these mods.