Help me find vaccum leak intake noise !

[89lxcoupe]

i just put rebuilt 289 heads that have been ported with 1.90 1.60 valves on my stock motor with a trickflow r series intake,professional products 75mm throttle body and egr plate and i have this loud whistleing sound that sounds like it is coming from the middle of the intake manifold i've changed the lower intake gaskets again with no luck i have rechecked every fitting and throttle body gaskets, i've sprayed starting fluid over every inch of the intake and throttlebody and injectors. i just can't figure it out. any help would be appreciated........ thanks

 

[Twistedoffpurp]

That sounds like the throttle body. Usually the larger you go with the throttle body the louder the wistle. I personally had a 70mm and it was loud but another friend of mine had a 75 and it was twice as loud as mine. Have you driven the car around to see if it does it cruising around?

 

[89lxcoupe]

i've heard 70mm throttle bodys do it at part throttle driving but never idleing. it sounds like its right in the middle of the intake, if you put your ear on the intake its loud .

 

[HISSIN50]

If you want to: you can seal off all vac ports on the plenum and intake. Leave one port available for your vac tester to connect to. Disable the ignition/fuel system and crank the motor over. You should see 3-9" hg on the gauge. Less than that and you have an issue.

Good luck.

 

[86bluecobra]

to find vacuum leaks i get a tiger torch and i run the propane over the area's you could have a leak while the engine is running. if you hear the idle rpm pick up whill you run the propane over the engine you have found your leak.

 

[89lxcoupe]

i have a vaccum gauge so i might try the cranking test ! i just done a search and i think its my 75mm throttle body causeing the whistle !

 

[SMOKEDYA]

I had a trick flow street heat intake with a 70mm tb and had the same thing. So if it dosent runn funny i wouldnt sweat it? peace





john

 

[Roland69]

ask a shop if they have a smoke box. We have one at work and it will show you where the leak is fast.

 

[89lxcoupe]

i wonder if a beehive smoker will work ! i know somebody who has one of them.

 

[Roland69]

if it puts out a few psi it should do the trick

 

[89lxcoupe]

how does the smoke box work !

 

[Roland69]

blows a smoke in a vac line and if you have a vac leak it will show.....kinda like a fog machine

 

[Roland69]

http://www.thesmokemachine.com/ViewLeaks.html

 

[89lxcoupe]

thats cool thanks i need me one of them !