ever since i have installed my header, there has been this high pitched whistling noise, but it only happens under semi and hard acceleration. on idle its quiet and on the highway there is no high pitched noise. It kind of sounds like an exhaust leak but, i used new gaskets and everything and tightened all the bolts solid. what do you guys think?

 

need more info on your car and what have you done to it.

 

my skunk2 intake with just a big filter on it makes a whistling noise kinda like a supercharger, I kinda like it.

 

After installing your new header, did you check for leaks?

Also, did you make sure the gaskets are in the perfect place? Sometimes, the gasket can shift when you are tightning the bolt and it can restrict the flow by sticking out from the side which might be able to cause a whistling sound.

 

i have a 94 honda prelude si, with cai, exhaust, header, venom 400, thats bout it. IT may be a gasket thats not on completly straight, but i may be losing my hearing cuz i swear it sounds like its coming from the back of my car (near the muffler) I will look at the gaskets tommorow i guess

 

For some reason when I installed my header, my heat shield rattles like a **** under load around 3500-4000 RPMs. Could it be yuor heat shield?

 

no not the heat sheild, and its not a rattle either is definatly sounds like AIR flowing....but i read a little in my chiltons, and i think it may be one of two things, it said that if you leave ur pipe unsupported that it can crack....maybe my pipe has cracked near my muffler....or....I dont think there was a gasket between my collector and catalytic converter, if there was one on there its still there cuz i sure as hell didnt take it off. I didnt replace that either. I will look tommorow.

 

the best way to find an exhaust leak-------- pull off the hose on the intake manifold that goes to the brake booster. put your thumb over it while somebody starts your car. use a bottle of DEXTRON III w/ MERCON (regular ATF). pour it in the vaccuum tube on the IM as you slowly move your thumb. it will suck it into your engine, and smoke profusely. dont worry about it hurting the engine, all it will do is clean off some carbon buildup. the only thing it can do is foul the plugs from all the smoke, but new plugs are like 8 bucks. put the vaccuum hose back on and give it some gas. smoke will come out of all exhaust leaks. you have to do this fast, cause it will stop smoking after all the tranny fluid is sucked through. after you find the leak, youll probably have to run it up and down the street for a minute to get all the ATF out. i promise it wont hurt anything, so dont worry about that. it actually helps. but you will definitely find the leak.