Ok so I have 900 miles on the car and started to venture in the upper RPM range for the first time. So I go full throttle in 3rd but as soon as I hit 6000 RPM I hear a loud, almost induction sound. This doesnt make since because the turbo is not really at full boost at this moment... It sounds like something is winding up real fast. I know its coming from the drivers side of the engine bay, so the only thing I can think of is turbo.... Its kind of hard to explain and i dont want to take it to the Stealership and have them wood my car from 6k up.
Anyone else get a weird sound right after break in, in the very upper RPM range..?

 

Your kidding right? At 6 grand and up, all of your 122 cubic inch monster is working and the turbo is spinning like a weather vane in a hurricane and the intake could suck the crome off a trailer hitch; the gizmos spinning and sucking at maximums makes noise! Enjoy it!!!!


Speedlimit....

 

it just doesnt sound good though, sounds like the turbo is going out at that high RPM....Or something on the transmission side is winding up...it could also just be because thats the first time ive actually brought it up close to redline....

 

it sounds more like somethind winding up on in the tranny rather than boos from the turbo....

Shouldnt the turbo sound loudest at full boost (19.5 psi) around 3800-4000 rpm. Why would it be louder at redline?

 

yo man that noise is viscious i dont kno how you could complain... first off think of this... yes u will hear the turbo SPOOLING the hardest at peak torque 3500 rpm that is not peak hp... keep that in mind..second..our stock bo vents at 19... our stock boost in 18.6 not 19.5 i dont kno where the hell u r getting that number from.... now if u dont let go of the accelerator before hitting the high rpm range... u still have the air u got from 3500 + all the air u r getting on the way up there basically chillin....think about it

 

hmmm ill go try it out again at lunch, go for some WOT runs..

What im saying though, the boost is not THAT loud at 3500rpm, something is LOUDER at 6000-6500 rpm, but it doesnt really sound like boost. Sounds almost like something is starting to wind up on the drivers side of the car. Maybe im just overly paranoid eh? Oh, and i thought 19.5psi was max stock boost... sorry dont have a boost guage yet =(

Im running 94 octane with 3 gallons of 101 mixed in, would that make anything sound out of the ordinary up top? Im just trying to prevent knock for my hard breakin...

 

the RPM of the turbo increases as the RPM of the engine increases...the wastegate is bleeding off boost but it is still spinning up

 

your right, i didnt think about that.... the turbo RPM will keep on going up even though max boost has been reach correct? I will try to confirm if it is the turbo at lunch...

 

do you all hear a louder induction sound from 6000-7000 though? Thats really what i want to know...?

Is this sound louder than anywhere else in the rpm range

 

wel i dunno...i am just a car guru in general...i hope to get an Evo this weekend though

 

I need some EVO opinions! lol

Hope your EVO purchase goes well, dont let those Stealers charge anything over sticker...

 

i already have a MSRP deal locked in but i have to get a good amount for my trade...thats the only thing that will stop me

and...you Evo owners help this guy out

 

Absolutely!! Have fun!!!

Speedlimit..

 

Yes, the actual measured boost is a function of three things. How hard you are cramming air into the intake, minus how hard the engine is sucking air out of the intake, possibly limited by the level at which the wastegate opens. At 6500 rpm, you are cramming air into the intake harder than at 3500 rpm, but not enough to make up for the fact that the engine is sucking air out of the intake at almost twice the rate -- either that, or you are wastegate limited (as mentioned by Longfury).

So turbo impeller speed keeps going up, but eventually, measured boost goes down -- that's the natural way of things with a turbocharger.

 

i am just a car guy...all cars from clasiccs to modern classics...so i may not know specifics of everycar but i have a good working knowledge of how most of there systems work

glad i could help though