I have the throttle body in, adjusted my ide, checked my TPS sensor. Now I take it out for a drive, it seems to hiss, or almost squeal at part throttle, and then goes away as I give it more gas. Is this normal air flow through the piece? Or is there something I can do to lessen it. It sounds to be squeaking and its just as the blade opens...

Thanks

 

That is the way it is supposed to sound. Pretty cool huh.

--Joe

 

Its normal and i love that sound. I also like the sound of when you have an filter kit on the truck and you shut it off and you hear the hiss of the air coming out.

 

What is that hiss by the way. I can't run around to the hood fast enough to see where it's coming from.

 

Not sure but I know it has nothing to do with the blower. My cousins 97 F-150 does the EXACT same thing every time he turns his off too.

--Joe

 

I had assumed it was probably to be expected, and enhanced by my filter kit. I hadnt noticed any problems with it before i put it in, but I figured if it was a problem, or something unusual, someone on this site would know about it. Thanks for the reassurance. And I do love it, SOTP meter says I got the torque back that I lost with the filter, and the stares indicate it sounds as good outside the truck as it does inside.

Thanks

 

Mine almost sounds like something is still spinning and eventually stops after 3 or 4 seconds. Perhaps the A/C pump or something?

 

About the air after you shut it off...I had assumed it was essentially purging the air that had been in the intake, that it couldnt use, so it was coming back out, but I could be wrong

 

NJLightning01
You felt a loss of torque with an air filter. Was it just a drop in panel airfilter or was it a airfilter kit? I really dont see why you would loss torque from the air filter i gained boost with it and truck felt stronger not like it lost anything from it. I never read anyone on this board lossing anything from an airfilter kit in all the time i have been here. As for the TB most people agree that you get the most out of it when being used in conjunction with an airfilter kit.

 

The hiss/whistle comes from the exit of the T/B being larger than the entrance of the upper intake. A slight missalignment causes the wistle. If you take a Dremel type tool and open up the upper intake to match the T/B it will go away. If you open up the intake make sure to carefully align the T/B and intake. The T/B should be aligned rather than just bolted on. It does make a difference.

 

Thanks for the advice about the dremel, I have a friend who does porting and polishing, I will have him look at it. About the filter, I felt like I lost some bottom end, possibly due to a drop in pressure. I did feel stronger through the power band, and top-end, including an increase in boost. But seemed less strong off the line, which might have been a good thing, at least for my tires

 

About the dremel...what kind of attachment will I want to use to grind that down, and what type of metal is the upper-plenum made of? My father has a dremel, but he said you need different grinding stones for different metals

Thanks

 

The upper intake is cast aluminum. I used an 80 grit flap wheel to remove the bulk of the material, then switched to a 120 grit flap wheel to smooth things out. After that I used felt wheels and compound to polish it to a mirror finish.