4 Horsemen Racing

Great service

Took a long time for the order to process and ship. Other than that didn’t really have a problem. Product came in perfect condition.

It does not clear the cel, installed on a 2017 GMC Sierra 1500 Denali 5.3 with Kooks long tubes & catted y pipe. Definitely have to play around with it to get to fit, had to buy extra extensions.

After installing Autotech piston stft on wot stft maxes out and eq goes lean. before 4000 rpm. Runs fine at part throttle.

Fast shipping. I emailed and left voice message regarding problems with the mount but never got a response. And I found out later their price was higher than the manufacturer’s.