snorkles

[newbib2]

so im building my first snorkle.. the guy at home depot is a wheeler from what he says.. well when he and his buddies were doing some tests, every 6" you loose "air" and hp.. this true?? right now im following the tech pages but using 3" pvc with a stack and 2" pvc inside the bay..

 

[blue88b2]

highly dought it, esspecially with a 3" tube. i noticed no difference.

 

[newbib2]

alright cool thanks for the reply!

 

[pimtool]

I didnt notice any difference either.

You can put a vacuum guage on your intake and snap the throttle if it drops to zero you are getting enough air. At idle it should be 17-21 Hg.

 

[Evan]

Lol....I wonder where the 6" number came from?

I just asked my girlfriend, who is an environmental engineer, about this. She said one way to calculate this is by using the Darcy-Weisbach equation. You need to select the correct friction coefficient from a Moody diagram for the pipe. I doubt a guy working at Home Depot knew this.

Δp = λ (l / dh) (ρ v2 / 2) (1)

where

Δp = pressure loss (Pa, N/m2)
λ = D'Arcy-Weisbach friction coefficient
l = length of duct or pipe (m)
dh = hydraulic diameter (m)
ρ = density (kg/m3)

If you actually perform the above calculation, you'll find that the headloss from adding another 6" of 3" dia. PVC pipe on an engine intake is next to nothing.

FYI, she wanted me to note that she normally works with water, not air, but is still confident in her answer.

 

[newbib2]

ya i didnt think it would make any difference. if anything should breath easyer.. just like the exhaust effect. plus it gets colder air from the outside of the engine bay too.