Odd noise while accelerating. Other civic owners experience this? whats the cause? solution?

Question

I own a 07 Civic Coupe with slight modification. I've added front upper strut bar, lower front tie bar, lower H-Brace, lower rear tie bar, bosch platinum electrode iridium fused 4 spark plugs, KN air filter. I dont think this would matter.

When i accelerate, normally, there are two "engine sounds." one is the sound of the rev where it changes gears and there is this other sound, a constant noise as it picks up to higher speeds. at 60-65mph, this constant noise is reduced almost silent, once out of that range its back again this time louder and its constant. I assumed it would be the stock mufflers but im not sure. Has anyone experienced this.

again one is the transmission shifting, it may be a noop question, it sounds more like vroom, shift, vrooom, shift, vroooom.shift... lol and as its increasing speed, 30 -> 45 -> 60(silent)65 -> 70,80

next time you are on the highway minimum traffic try it. try getting to 60-65 and stay there, and then get higher(IF POSSIBLE)70,80. youll kno what im talking about.

I HATE THAT NOISE LOL. any help

Answer 1

Its sucking big air through that k&n. Put your stock filter back in and see if the noise goes away. You owe me 20 if im right.

Answer 2

if its a constant sound directly linked with the speed of the car, it could be an alignment issue... and for some odd reason it doesnt make the sound or dulls at that range... or tire noise... my car makes a h**l of a lot of tire noise, but around 60-70 its pretty quiet but again it makes noise when I am over 70...

Answer 3

check engine mounts run car with hood up watch for engine travel when you accelerate.