Intake pipe diameter

[Wedged'86]

Yo i had a search and turned up nothing.

I've got some 2.5'' stainless pipe and i was wondering if this is an alright size to make up an intake outta? it's for a bigport 4age.

Thanks.

[oldcorollas]

before or after the TB?

mod edit - despite being correct, i will try and be less inflammatory, at least in the first instance

[Wedged'86]

Before it.

mod edit - my sig is immature, is not reflective of the toymods responsible driving philosophy, i will change it, and i have no further arguments to make about it.

[roadsailing]

2.5 is a tiny bit small, can;t remember. measure the OD of the throttle body inlet and size off that.

I'm running 3 inch pipe and it needs a reducer to fit on to the TB, used is as i got the bend for free and it enabled me to get rid of my old bunnings special PVC intake piping.

[Wedged'86]

a tiny bit too small ey?
I've got this pipe sitting around and it'd be good to find a use for it. you reckon i should go bigger though?
2.5'' too restrictive?

[oldcorollas]

try it, dyno it.. see if there is a difference
what size is stock? what do you have on there now?
if you want to do it.. do it anyway and see what happens

[roadsailing]

just measure what the engine wants! its all very well to have shit lying aroudn that you want to use, but the need should require the thing, not the other way around. i can see a few empty beer bottles here, but i;m not trying to figure out a way to make intake pipes out of them.

[Wedged'86]

ahhh...... ok

oh and there's nothing on there now OC it doesn't have one.

[roadsailing]

from hazy memory the TB inlet is about 75mm in diameter, so go from there.

[Wedged'86]

Thanks man, i didn't mean to give you the shits i was just trying to find out whether to use this pipe or not. i don't have a TB as yet so i couldn't measure it.

Thanks.

[jimmmayyy]

Approx the same size as the TB is ideal I have heard, slightly smaller to accelerate gas flow, but lower flow.. or slightly larger for greater, but slower flow. The only real way to find out is on a dyno I suppose though.

[IN 05 NT]

from hazy memory the TB inlet is about 75mm in diameter, so go from there.

75mm on a standard 4age??????????? that must be OD not the ID which is what matters (otherwise thats a MASSIF TB)

the ID of 2.5" pipe is 58mm... so if the TB ID is smaller this will be ok. (unless your going to have the pipe PRESS BENT), which then reduces flow in the tight spots.

[BlackSupra]

75mm on a standard 4age??????????? that must be OD not the ID which is what matters (otherwise thats a MASSIF TB)

the ID of 2.5" pipe is 58mm... so if the TB ID is smaller this will be ok. (unless your going to have the pipe PRESS BENT), which then reduces flow in the tight spots.

Im with blake, A 75mm throttle body is huge, a 7m is only 62mm or so and im pretty sure a 4A throttle body is smaller than that.

And yes, your signature is crap, i would highly recommend changing it.

[ed]

posts moderated above. please take note

[Dieseltrain]

What size PoD are you running? If its a 60mm then the 2.5 inch will be perfect