3-Hole Mod

[BowTie]

So I was quite happy with the 2-Hole until foamy mentioned something the other day.

Upon investigation, the hole in the upper airbox that supplies the afm is tragically small. I hadn't noticed before as its kind of hidden behind the flange plates.

So out came the 90mm holesaw again. Then a temporary flange and connector had it sorted.

After two decent drives now, I am convinced there is a significant gain in the bottom and mid plus a crisper throttle response with no penalty. Enough to redo it properly and post pics as to what im on about.

Going to try a 4" elbow next between the afm and tb for shits and giggles.

[sweefu]

Sousd good mate i might give it a shot, do you have any pictures or a how to?
Cheers.

[Klint_VS]

3 hole mod??

[ParkwayDrv]

3 hole mod??

yes you can count

[BowTie]

Pics soon.

[nathanVY]

sounds interesting, let me know.

[fkford]

so this or a CAI?

[Ozzie]

You might gain colder air but not more air.

[BowTie]

S/C CAI is hole 1.

90mm hole & flange in bottom of lower airbox is hole 2.

90mm hole and flange in upper airbox is hole 3.

Simple really.

[Ozzie]

S/C CAI is hole 1.

90mm hole & flange in bottom of lower airbox is hole 2.

90mm hole and flange in upper airbox is hole 3.

Simple really.

Whats the diametre of your throttle body? 180mm?

One 90mm hole would be sufficant enough to go through a 80mm throttle body.

You wont get any restriction in flow from a single 90mm, what you want is colder air.

[BowTie]

It is a single 90 airbox exit hole to the maf.

The first 2 holes supply the filter and the third supplies the maf.

I will MSpaint it just to make it even more confusing.

[BowTie]

+ hole 1 & 2 are both CAI's.

[Ozzie]

I will MSpaint it just to make it even more confusing.

i dont think its possible to confuse the situation more.

+ hole 1 & 2 are both CAI's.

Whats the point of havin a filter at all then if theres a hole straight to the maf?

[fkford]

i dont think its possible to confuse the situation more.



Whats the point of havin a filter at all then if theres a hole straight to the maf?

exactly what i was thinking

[BowTie]

You are over complicating it.
All I have done is expand the existing upper airbox from 76mm to 90mm.



The grey flange is the key bit. I have temporarily connected it with the old hose and a 15 degree elbow but you should use straight 90mm silicone in black and paint the flange black so it still looks stock.

Now look at that hole and imagine a 76mm restrictor plate where the grey flange is coz thats how stock ones are.

[The1]

i wonder if the stock super 6 has the same restriction?

[hsv91ss]

I must do this when I get the chance, though I can't find the guide for the 2 hole mod on a VS airbox.

[Not_An_Abba_Fan]

Everyone talks about restriction. GM spend millions on R&D but you come along with a hole saw and think you know better?

It doesn't matter how big you make those holes, the size of the throttle body determines how much air can get into the engine.

[lothaer]

would fitting a heatsink in there help? maybe a Golden Orb 2?


just a idea feel free to flame

[sweefu]

Hey mate,
did you notice any gains in power or throttle response or anything at all?
cheers.

[neet_wagon]

How about you give his idea a chance.
He has a well respected (greenfoams) tuners opinion on the subject,
he hasn't just gone an cut a hole in it.
Holden didn't put it there because Holden are a useless bunch of c*&ts

All you people that dis an idea before you give it a chance at success,
especially when everyone raves about the supreme awesomeness of the '2hole' mod,
when all his done is complete the process the '2-hole' genius' only got halfway through.

[BowTie]

Turbulence/turbidity across an inline gauge is bad.
Holdens 76mm restriction causes a venturi effect 1.5 pipe diameters before the maf and disrupts smooth flow.

Everyone knows ?? that placing an in line measuring instrument in a pipe optimally should 4 pipe diammeters from the nearest bend or disruption of any kind.
Since this isnt achievable with current space restrictions, I have only tried to smooth the supply flow to the maf. I suspect any gain has come from the increase in maf accuracy and not a gain in flow.

Yes, I am just playing around. Nothing conclusive yet.
For the record, i'm an aluminium diecaster by trade. I have cast tens of thousands of v6 ecotec inlet manifolds and sumps and have spent more than a couple of minutes talking to people about them.
For the last 10yrs i have run a 10Mw snowmaking facility, largest in aus, so I may just know a little bit about pressure, flow, measurement, metallurgy, thermal conductivty, expansion co-efficients and last but not least, Holden.

Besides, there is another thread in v6 mods where people are trying all sorts of stuff with their upper airboxes. I am just trying to come up with the same thing that appears stock to the untrained eye.

[nathanVY]

good work mate, keep us posted.

[Not_An_Abba_Fan]

Doesn't matter how much experience you've had doing what, there is only so much air that can get into the engine at atmospheric pressure, and no amount of increasing holes or flow in the inlet tube will affect that. You may be able to change flow characteristics but you won't alter volume.

Someone said earlier you need to change the temperature of the intake air, not the flow or volume.

[Ozzie]

Doesn't matter how much experience you've had doing what, there is only so much air that can get into the engine at atmospheric pressure, and no amount of increasing holes or flow in the inlet tube will affect that. You may be able to change flow characteristics but you won't alter volume.

Someone said earlier you need to change the temperature of the intake air, not the flow or volume.

Yeah that woulda been me.

This whole project hes making here is a complete waste of time, energy & money.

Not sure exactly how many mm the stock TB is but as an example I find it hard to believe altering a 70mm TB to a 70mm pipe into a 90mm end will do anything at all.


^^^ I recon that golden orb fan would be more effective lol