Just installed mine the fit was okay had to do a little adjustment might’ve been because my truck is lifted but overall I’m very happy with my purchase
Made the truck like a vette with X pipe and 2.5in tips out the back c7 style.
Just installed the 1 3/4th long tube headers on my 99 5.3 4x4! excellent fit. 0 modification needed. Both fit right in like A glove. I’m impressed with the sound and the throttle response and fitment. These are must!🔥 thank you speed engineering.
I want to state that the set I have on my 2001 Silverado were purchased back in mid 2016. They have been on the truck since and have held up well. My only gripe is the 02 sensor bung location on the passenger side. The sensor hits the floor. I had to run an adapter to turn it sideways. I have installed 2 other sets on this generation of truck since with no problems, so I assume this was an early production glitch that was taken care of. When I have my truck apart to do a different set of cylinder heads - I plan to plug off the factory bung and weld in another one in a better spot.
The headers are a perfect fit. No modifications required and engine sounds amazing now prefect combo with the true dual exhaust system also.