Plumbing the air intake on EFI engine buggy

[rcx132]

Just trying to figure out what the air intake will look like on my buggy as I need to get an idea of where the MAF will be located so I can provision for it in the wiring loom.

The pic below shows the engine in the donor car. The MAF (3) is located by the air box. There's also two small air hoses that Tee off from the main 64mm pipe labelled (1) and (2). Hose (1) goes to the cylinder head, so is that just a breather? And (2) goes back to a component that has the IAC / Idle Controller on it. So is this an air intake for the idle control mechanism? Do these two hoses have to be downstream of the MAF ? Could they also draw from a separate filter, as I'm not sure how I will Tee them into the main intake if using universal air intake parts.

 

[rcx132]

I've found some silicone reducer and connector hoses that will let me connect the MAF to the alloy engine manifold.

I've also found a reducing 70-70-25mm Tee, seems to be designed for dump valves, but may let me plumb the two small hoses (1) and (2) into the main intake. The Tee reduces to 25mm which is too big so I'll need more fittings to complete the plumbing.

 

[8ob]

You will need to check to see if restrictors were installed on any of the pipes/tee`s that connect any of the breather system to the inlet side of things.

Bob

 

[rcx132]

You will need to check to see if restrictors were installed on any of the pipes/tee`s that connect any of the breather system to the inlet side of things.

Bob

The hose that goes to the component with the idle control valve has something fitted inline. What could this be?

 

[rcx132]

The small outlet on the eBay Dump Valve Tee is 25mm. All the Tees on eBay are this size. But the two breathers on my engine are 14mm. I'm starting to think I'll need to machine a 25-14-14mm Tee :/

 

[rcx132]

You will need to check to see if restrictors were installed on any of the pipes/tee`s that connect any of the breather system to the inlet side of things.

Bob

The component that sits inline on the hose that goes to the idle valve looks like an empty box.

 

[rcx132]

What car are we looking at

The engine is from a Vitara (the original hairdresser model), it's going into a 4x4 tube buggy. Buying the original pipes is an option but I like the idea of using universal parts that will make it easier to add a snorkel later.

 

[8ob]

The component that sits inline on the hose that goes to the idle valve looks like an empty box.

View attachment 390146 View attachment 390147

No idea, all I am saying is be wary of omitting or changing anything connected to the inlet. The whole pcv and any other air admittance systems are dialled into the fuel mapping. A mate of mine did similar on a Ford, ran like a pos afterwards, eventually found a brass bung with a tiny hole in it pushed down one of the pipes he had replaced, just saying look carefully at whatever you are changing.

Bob

 

[Neilj]

Idle air needs to flow through the MAF unit, so hose (2) needs to be downstream of the MAF as it is now. The funny looking box is probably just a damper, something with a bit of volume to dampen out any pulses in the air flow. The breather hose (1) should really be downstream of the MAF as well, if it was connected upstream then you may be oil mist contaminating the MAF unit

 

[rcx132]

Thanks. That answers most of my questions. That leaves me to figure out how to plumb in those two small hoses. Either buy the Tee with the 25mm outlet and reduce to 14mm, or have a Tee made.

Does that funny looking box have a part number on it?

Good idea. I looked it up in the parts catalogue and it's labelled as "1814558B00 CHAMBER, ISC". It is in the Emissions section of the catalogue. One online shop describes it as the "CHAMBER, IDLE". Maybe ISC is Idle Speed Controller?

 

[Robotstar5]

Idle air needs to flow through the MAF unit, so hose (2) needs to be downstream of the MAF as it is now. The funny looking box is probably just a damper, something with a bit of volume to dampen out any pulses in the air flow. The breather hose (1) should really be downstream of the MAF as well, if it was connected upstream then you may be oil mist contaminating the MAF unit

That probably explains what the 2 plastic cubes are on my Suzuki, they are empty and just stabbed into the intake after the air cleaner.

 

[rcx132]

I agree with Neilj its probably just a damper. What do you plan to use to connect the MAF+airbox to the intake? A metal pipe will allow you to add fittings for these vac hoses.

I've done some online browsing and it looks like engine tuning shops sell silicone hoses, reducers and fittings to plumb this all up.

 

[redlig]

No idea, all I am saying is be wary of omitting or changing anything connected to the inlet. The whole pcv and any other air admittance systems are dialled into the fuel mapping. A mate of mine did similar on a Ford, ran like a pos afterwards, eventually found a brass bung with a tiny hole in it pushed down one of the pipes he had replaced, just saying look carefully at whatever you are changing.

Bob

Agreed ! From past experience leave it all as per standard unless you really know what you are doing. The manufacturers spend millions developing a workable system and along comes a guy in a shed and redesigns it with possibly only basic knowledge . I'm not saying it can't be done but usually ends in tears.

 

[redlig]

That probably explains what the 2 plastic cubes are on my Suzuki, they are empty and just stabbed into the intake after the air cleaner.

View attachment 390182

Plenum chambers?

 

[PhillipM]

That probably explains what the 2 plastic cubes are on my Suzuki, they are empty and just stabbed into the intake after the air cleaner.

View attachment 390182

They're helmzholt resonance chambers they'll be there to cancel out an annoying intake hum usually, occasionally to fill a dip in the torque curve from other effects too.

 

[redlig]

They're helmzholt resonance chambers they'll be there to cancel out an annoying intake hum usually, occasionally to fill a dip in the torque curve from other effects too.

I new as soon as I posted it I had used the wrong name .

 

[Robotstar5]

They're helmzholt resonance chambers they'll be there to cancel out an annoying intake hum usually, occasionally to fill a dip in the torque curve from other effects too.

Shame I'm too old, "I've got a nice pair of helmzholt resonance chambers, would you like to see them?" would be a good pickup line

 

[rcx132]

Plenum chambers?

Ah that reminds me, would you look at my original photo, above the MAF (3) is an air chamber on the side of the main intake pipe. What could that be?

I agree with @8ob and @redlig to keep everything as original as possible. But within reason. If I use the original pipe then my airbox will be in the wrong location. The original system is also impossible to make a waterproof seal with a snorkel as it's an odd shape.

 

[Neilj]

Ah that reminds me, would you look at my original photo, above the MAF (3) is an air chamber on the side of the main intake pipe. What could that be?

Are there any other hoses or connections to it apart from the one to the air intake pipe?

 

[redlig]

Shame I'm too old, "I've got a nice pair of helmzholt resonance chambers, would you like to see them?" would be a good pickup line

Tried that !! Took me two weeks to regain my hearing.
Also tried F.M.P.O. ( for medical purposes only) Also failed!