3.2 DiD intake butterfly removal

[k100dennis]

Is it possible to remove the butterfly from the intake manifold ? I have all the EGR system removed and was thinking the butterfly only serves to assist with creating some vacuum during exhaust gas return. Is this correct, and can it be removed ? I prefer to not have unnecessary bits. Ideally I would like to replace the whole assembly with a spool piece.

[Kingmarz]

Yes it can be removed but it will throw a CEL at idle and it can be a little hard on the engine mounts on shutdown also occasionally get engine running on for a couple of seconds. And yes the computer controls the butterfly at certain acceleration positions to allow exhaust gasses pressure exceed intake pressure (boost) so it can travel through the EGR into combustion. Is it worth removing?
I say yes go for it.
Also remove the little EGR bucket thingy in intake manifold. It has to be pulled out and cannot be pushed in. And intake pipe stationary fan restriction thingy before air box cut or melt that out.

[JHwick]

Is it possible to remove the butterfly from the intake manifold ? I have all the EGR system removed and was thinking the butterfly only serves to assist with creating some vacuum during exhaust gas return. Is this correct, and can it be removed ? I prefer to not have unnecessary bits. Ideally I would like to replace the whole assembly with a spool piece.

How'd it go - did you get around to removing the butterfly assembly?
Just fitted a new ebay intercooler to my NM DiD and streamlined the intake pipework. Found some noticeable improvements with less restriction, so I'm keen to tidy things up a little further.
EGR was blanked off ages ago BTW...

[Kingmarz]

How'd it go - did you get around to removing the butterfly assembly?
Just fitted a new ebay intercooler to my NM DiD and streamlined the intake pipework. Found some noticeable improvements with less restriction, so I'm keen to tidy things up a little further.
EGR was blanked off ages ago BTW...

Was the cooler a kit or did you custom?
I’ve removed inlet butterfly on my 02 NM only because of bad idle from bad solenoid and now get CEL.

[JHwick]

Was the cooler a kit or did you custom?
I’ve removed inlet butterfly on my 02 NM only because of bad idle from bad solenoid and now get CEL.

Thanks for the info.
May wedge the butterfly open on mine, just to see what it does at different engine speeds.
Surely a free and open air passage would be better for the engine?

Intercooler is a generic V-mount with some bends to connect it to the stock IC piping.

[JHwick]

Just disconnected my vacuum lines and secured the butterfly in the open position with a cable tie.
Started and ran just fine but tended to run on a little when the engine was turned off.
Reconnected everything afterwards and had a closer look at wat the butterfly does in operation.

On my non-common rail 3.2 DiD, fully open appears to be the default position for the butterfly. It remained that way on idle and when the engine was revved. The only time I saw it move was when the engine was turned off.

Looking down the guts of the intake with a torch, it doesn't look like the open butterfly plate would create a lot of restriction. Given the run-on issue that I encountered when turning it off, I think I'll leave it be ... unless someone out there has other ideas.

Here are a few photos of the intercooler. It's more than twice the size of the stock low-mount Mitsubishi unit and gave me 2psi more at the intake manifold, so it clearly flows better.

[Kingmarz]

Just disconnected my vacuum lines and secured the butterfly in the open position with a cable tie.
Started and ran just fine but tended to run on a little when the engine was turned off.
Reconnected everything afterwards and had a closer look at wat the butterfly does in operation.

On my non-common rail 3.2 DiD, fully open appears to be the default position for the butterfly. It remained that way on idle and when the engine was revved. The only time I saw it move was when the engine was turned off.

Looking down the guts of the intake with a torch, it doesn't look like the open butterfly plate would create a lot of restriction. Given the run-on issue that I encountered when turning it off, I think I'll leave it be ... unless someone out there has other ideas.

Here are a few photos of the intercooler. It's more than twice the size of the stock low-mount Mitsubishi unit and gave me 2psi more at the intake manifold, so it clearly flows better.

Did you mount cooler with inlet/outlet facing down and how hard was it to mount did you do any cutting and what sort of piping did you need?
Cheers

[JHwick]

Did you mount cooler with inlet/outlet facing down and how hard was it to mount did you do any cutting and what sort of piping did you need?
Cheers

It was pretty easy with minimal cutting - just had to shave off a few mm to make room for the width for the new 76mm wide unit at the bottom. It's mounted on a 70-deg angle BTW but seems to do the trick.


Photos should explain the rest.

[Kingbrown]

Might be the camera angle but is one of the pipes touching/rubbing on your radiator tank ?

[JHwick]

Might be the camera angle but is one of the pipes touching/rubbing on your radiator tank ?

Nope, there's around 6mm of clearance and I'm keeping an eye on it — can drop it closer to the sway bar if it rubs.

[muzzy]

Why remove it?
It helps low down power by accelerating air at lower speeds.
By having it always open you'll love lose low down power.

[Muzza]

Why remove it?
It helps low down power by accelerating air at lower speeds.
By having it always open you'll love lose low down power.

The intake butterfly, only closes when you switch the key off to enable a quicker shut down, on the NP at all other times it is wide open, later Pajero the butterfly moves according to EGR demands.

[Kingmarz]

The intake butterfly, only closes when you switch the key off to enable a quicker shut down, on the NP at all other times it is wide open, later Pajero the butterfly moves according to EGR demands.

If that’s true then why has my NM Pajero have two separate solenoids operating two different diaframs controlling the inlet butterfly? From what I understood the inlet butterfly move to EGR demands since the release of the facelift 4m40 (2.8td) with the electronic pump back in 1996 which is a motor I believe was never available in Ausie. Correct me if I’m wrong of course.

[Muzza]

My bad, one solenoid to control on and off the other is to move according to driving conditions ( quote from my Mitsubishi training notes from 2002) oops forget , but then it was 17 years ago ��.

[k100dennis]

I was the OP, sorry for not replying earlier. No, I never removed the butterfly as I found out about the engine-run on and the CEL coming up. Not worth the effort. I may still remove the CAT from the exhaust though.