air intake

[Jake91]

hi i was wondering what is best for a dohc a 3in intake or a 4in intake


thanks

[robertisaar]

i think superdave's SAI would be best

[HayesPerformance]

I've been using 3" aluminum on the GM V6's ..... 4" would be good on like a SB V8..

[robertisaar]

4" would be good on like a SB V8..

4" would be WAY too much for a 3.4... the air velocity would drop to unacceptable levels.

[Jake91]

i think superdave's SAI would be best

what is this

[robertisaar]

Small Animal Intake

[Jake91]

4" would be WAY too much for a 3.4... the air velocity would drop to unacceptable levels.

well then is this a good set up

im going to run 3in part way and then up to 4in only so i can fit a 4 in filter on it because im getting a free k&n

[Jake91]

that sai would be sweet if you didnt need ha headlight and had filter

[robertisaar]

if you're going to transition between sizes, that is the way to do it.

that sai would be sweet if you didnt need ha headlight and had filter

Track use only...

[Jake91]

i figured it was only for track use.

[Jake91]

okay so like this setup would be okay

3in 45 degree elbow to 1 foot of 4in pipe to a 4in filter.


oh and a 9 in long filter isnt going to suck to much air is it?

[Jake91]

oh and this is all coming off of my stock intake hose

[robertisaar]

think of it this way:

you want the 4" section to be as short as possible that way it doesn't affect the velocity too much.

then a transition pipe.

then your 3" tubing. you want it to have as few bends in it as possible and the ones that are necessary need to be as smooth as possible. meaning a longer curve won't disrupt the airflow as much as a instant 90* curve. make sense?

some people say that you can't have too much filter. this is wrong. but the differences are VERY small and you likely would not notice the difference between filter sizes so long as they both flow adequately.

[Jake91]

so would it be best to run all 3 in and then just have an adapter for the filter?

[robertisaar]

EXACTLY.

you don't want that air trying to move through a 4" space...

larger pipe with same air requirements: slower air.