Alright here goes
So I had a problem with my radiator, so I basically decided to put a sheetmetal intake manifold on and my PPI ported TB on since the car was down.

initial impressions of the PPI TB are absolultely great, and it does perform a lot better than the stock one does,

here is my story, after installing the magnus, (almost catching my car on fire because an injector did not seat properly) and fixing numerous leaks in the system (it now holds 30 psi when I pressurize the system), I am still hearing a whistling sound coming from the TB area. Maybe its air turbulence catching certain areas of the TB while air is passing through it . Kind of like blowing air over a coke bottle. This whistling sound is only between -15 in/hg and -3 in/hg (in vacuum only)

so I was wondering if any of you who have a ported TB or aftermarket for that matter have experienced this phenominan .

possible solutions, --
polishing the inside of the TB and beveling the butterfly so that there are no sharp edges for the air to be turbulent over.

let me know and for god sake RTV your TB bolts because they do leak even if you tighten the **** out of them

have a good one
w

 

You mean put it on the threads itself or on the entire bolt???

 

it sounds to me like you are leaking out of the seals on the throttle body. i'm not exaclty sure why you would put RTV on the throttle body bolts themselves... they don't have any access at all to the actual intake chamber. as long as you put a gasket between the TB and the IM and the bolts are torqued to spec, it should not leak out of the "bolts".

if you are doing a boost leak test when you hear the whistling sound, try playing with the throttle cable where it attaches to the TB. that shaft has two seals and they very commonly go bad causing a boost leak. if you can't hear it, squirt soapy water on the shaft and see if any bubbles form. if so, you need to rebuild it with fresh seals.

 

I did use the soapy water method to check for boost leaks, THE Only reason that I rtved the bolts (only on the threads) was because I was seeing bubbles coming from the bolt area, I also checked the area where the shaft seals would leak and they were fine ... The entire system held 30psi of boost WITH NO leaks or formation of bubbles.

I will check with another ported TB and report back because it seems that I am the only one that is experiencing this problem (not really a problem just a pesky noise )

 

bubbles coming from the bolt area, you mean by the Tb to IM gasket? or out of the bolt head area? that is really unusual. did you reuse the gasket from stock? does it even fit the new IM properly?

 

i have experienced several whistling tb's & I havent isolated the problem, as i have swapped out seals & the tb still whislted other tb's went quiet?

I have noticed more whistling associated with oem cams on oem gears, but i do know someone who had whistling really bad with 280's???

i plan on sortinout a issue with a tb which whistled that has new seals while using 280 cams.

I will report my finidings.

 

KevinD -- the bubbles were coming from the bolt head area, so essentially seeping through the hole where the bolt is attached to the intake manifold (a magnus in mycase).. The gasket that was used is a new reemed out TB gasket that matches my 65mm TB . Yes everything fits perfectly on the magnus and there are NO leaks (soapy water test) around the magnus flange and the TB .

WOT -- this car has stock cams in it, I don't think that is what is causing the whistling, because with the stock TB and the magnus there was no whistling what so ever .

I am stumped

 

when i was dveloping my 65mm tb, i encountered a whistling noise with oem cams & cam gears.

When i retarded the oem cams, the whistling went away with the same tb & no other mechanical changes??

I dont understand why some tb's whistles, while others dont?

 

well I guess I can throw in my 272s this weekend and report back on whether the stock cams are to blame
thanks for the input