Yup, the 5303’s have beaten every header I’ve tested them against.
I have several engines getting ready to dyno. 340, 395 and 416 inches. I’m going to test them all with 5303’s and I also have a set of Hedman 1 7/8 headers I’m going to test too.
If I really feel like burning dyno time, I’ll test some TTI’s and some cheap *** headers I have that already beat the TTI’s.
I’ll see how it goes.