Intake port sound

[SBC]

So what do the intake ports sound like on the bench when you're done porting?

Any distant rumble/thunder?

Or just a steady sssssshhhhhh/white noise?

[ChadS]

Depends on alot of factors, but mainly it depends if the port was done right or not. An effiecient port will humm along cleanly, and when one stalls you will know as it changes pitch.

Chad

[bill jones]

-On low intake port heads you can usually hear the "tumble" across the short turn, on a 4 valve IRL Aurora head the noise is so shrill it about breaks your eardrums.
-If you have a swirl meter the noise and the big swirl number usually happen at the same time.

[cboggs]

So what do the intake ports sound like on the bench when you're done porting?

Any distant rumble/thunder?

Or just a steady sssssshhhhhh/white noise?

From my experience most of my good ports that ran well on the track had a very "clean" sound on the bench. Any time there was a "rumble" or other sound it was turbulence and the ports didn't run well on the dyno.

often any noise or "rumble" will be accomponied by the depression manometer jumping.

The above mentioned low ports with NO short turn, .. I do a bunch of 2.L pinto head for road racing.
The is NO short turn, when it's right the port is whisper quiet, .. when it's wrong it sounds like a category 5 twister.

Now in testing, if you have a port like this the first thing I do is use little balls on a welding rod to poke around and find the source.

[SBC]

A sincere Thanks for the replies guys!
Upper lifts.
The depression manometer moves less than a tenth.
Perhaps some sound comes from within the cylinder.
Lots of things to keep an "eye" on.

[cboggs]

A sincere Thanks for the replies guys!
Upper lifts.
The depression manometer moves less than a tenth.
Perhaps some sound comes from within the cylinder.
Lots of things to keep an "eye" on.

Glad to toss things around, .. it's fun to have people to talk about this stuff with.

This sound thing is hard to describe, . but if the manometer isn't jumping around, .. it might not be a problem. What depression are you testing at?
Small jumps at 10" h2o can be major turbulence at 28" h2o.

Curtis