First off i'm new and second a issue i have came across in my wrx sti 2001 the only mods that i have are 3" exhaust system and HKS intake. While driving in 4th-6th gear i come across a weird sound between 3000rpm to 4000rpm in 4th to 6th gear, but then after 4000rpm.
at 18 seconds of the video that's how my car sounds like. Another thing i'd like to say is how am i boosting 21 pounds only mods i've got is exhaust system and air intake that is pretty much it, but the only think thats bothering me is the noise between 3000-4000 revs only.Thanx, PS im new