Alfa Romeo Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
2,370 Posts
Discussion Starter #1
I'm curious and semi-interested in doing something with the intake hose that goes from the AFM to the throttle body. It's about 10 in long (16cm) and starts at 3 in inside dia and end at 3.5 or 4(?) in inside dia. It has some corrogated outside - probably for stiffness, and two smaller hoses attached to it. One goes to the idle circuit - some electric device that controls the idle, and one goes to the oil separator.

I'm wondering several things. Are the two connector any special type? ie, if a replacement hose with no holes were inserted instead, can the holes be just poked in and connect these two hoses, or is there something else going on?

Are the placement of these hoses along the length of the intake hose important? Is the length of the intake hose important?

I'm wondering this because as I look at this whole contraption, I wonder if this hose were shorter, I could have a lot more room for a different kind of air filter and maybe fabricate something to guide the air in from the opening next to the radiator.

If finding another AFM with the same diameter as the TB should be done at the same time, I'd like to hear opinions on that too. Is there another size available for that?

Thanks,
 

·
Registered
Joined
·
297 Posts
why bother? apart from maybe gaining two tenths of jack sh.. Go map and piss it all off together. :confused:
 
A

·
Guest
Joined
·
0 Posts
took me this long to learn to resize the xlarge images this new camera creates, hope the photo makes sense, the 2 ends are the sizes you mentioned. 75 TS's and 164's and Spider's were all from the same parts bin, many items are as close as the nearest "salvage" Alfa.
 

Attachments

·
Registered
Joined
·
452 Posts
alternate TB hose

Iachella-- alternate hose is as close as Auto Zone and similar auto parts sources. They stock corrugated cut-to-your-desired-length intake hose available w/ straight connectors or stepped adapters. The same vendor also offers an annular ring which can be inserted anywhere along said intake hose and contains the holes/connectors for oil separator, IAC valve or whatever you need to plumb in ahead of the throttle body. Hey, don't worry-- I won't tell where you got it, and besides you can cut it to fit and paint it to match satin black--the Rice racers will be none the wiser.;) I have read that the length from AFM to TB is not so important but you should have at least a few inches of straight, unrestricted hose BEFORE the AFM. Possible air cleaner tip: after measuring, looks like the air filter assy'. from a D-90 Land Rover Defender (mid 80's, USA version, pix on Ebay) will fit in my '74 GTV, with some careful effort. You probably have even more room in your Alfetta. It's a dead simple round can with latches and a proper element and has the right size rubber connector outlet. The intake trumpet looks as though it could be shortened and plumbed directly to the cold air intake:D Rave on.
 

·
Registered
Joined
·
2,370 Posts
Discussion Starter #6
Capp - Excellent suggestions. I found the picture and it looks very Spica-like. I don't mind Auto Zone either. I befriended a Mitsubishi rice rocket kid behind the counter who let me browse all the radiator hoses in stock to see what I could get to fit. They are all aware of imported engines that don't quite line up.

Hugh - I'm on the MAP trail too. I found a guy who is making a kit to plug the Bosch connector to a Ford MAP and the signal will be correct to the Motronic ECU. He's a BMW guy and has put a few newer BMWs engines into older BMWs. He's an electronics and robotics guy and plans to sell it at a low cost. I told him us Alfa guys could be quite interested in it, so he'd like to test it on my car soon. I'll keep his name to myself until we do that (I'd like to get a discount or free one in the process). I will certainly post for anyone to contact him after that.

The idea of the short tube will not conflict with this conversion either. It's just to gain some room in the engine bay for a better air filter solution.
 

·
Registered
Joined
·
2,370 Posts
Discussion Starter #8
Just checked out my previous communications with him and it is programmable. There will be several maps to chose from or you can download your own map.

Correction though - I had said it uses a Ford MAP. It is a Ford MAF. I think that is the heated filiament to sense the air flow, not the vacuum to sense the air flow.

It was supposed to be ready late August. I'll check in with him soon.
 

·
Registered
Joined
·
150 Posts
just change stock hose with short one of your choise ... eliminate 2 small hoses
one is from oil separator -> put breather filter direct on separator :) other is for
iddle solenoid again put some small filter direct on solenoid and you are done :)
 

·
Registered
Joined
·
2,370 Posts
Discussion Starter #10
Good idea TS-turbo, I could do it for the idle, but for smog purposes, I think I'll have to plumb the oil vapor separator to the intake. I don't see how the idle would be important to smog, but you never can tell, I'm in California after all.
 

·
Registered
Joined
·
2,370 Posts
Discussion Starter #11
I was wondering something else with repect to the idle filter. If all the air at idle come from an external filter, the flap would never be open at idle, right? What effects on the signal back to the computer would that cause? I'm not concerned about the fuel pump relay as I'm not running my fuel pump with this scheme. I'm talking about the flow signal for the mixture.
 

·
Registered
Joined
·
199 Posts
Afm

Hi Stefano

Like you, I've looked into replacing the vane-type AFM on my Spider with a mass air flow sensor in a somewhat bizzare search for improved air flow. The Bosch HFM5 seems like a reasonable alternative. http://rb-aa.bosch.com/advastaboschaa/Category.jsp?ccat_id=129&language=en-GB&publication=1

The HFM5 can be mated to a Split Second PSC1-004 ( http://www.splitsec.com/ ) but the issue is primarily cost, with the total package costing north of $500. The SS unit is also more complex than it really needs to be as it has a 3D map consisting of both the MAF output and rpm signal. Although it could be an interesting way of tuning an Alfa.

So, I'd be interested in hearing what your friend has to offer.

Best regards
Simon
 
1 - 12 of 12 Posts
Top