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Discussion Starter #1 (Edited)
I am looking at 3 things
1 VAF to AFM,
Reasons, replace the VAF with a MAF, no moving parts, no tracks to wear out, no spring that gets weak over the decades leading to inaccurate output.

2 coil to DIS, wasted spark, CNP, or COP
more accurate powerful sparks, no coil, no distribution cap, no rotor, no parts that fail in damp conditions "still got the HT leads...." or electrodes that get worn down.
Buchka Wasted Spark Board Installation Instructions – CFloMoTo

3 remapping of Bosch Montronic ML4.1
off the shelf chips wont be as accurate to an individual map to each car
pcmhacking.net - View topic - Alfa Romeo Motronic XDFs
pcmhacking.net - View topic - MotronicPlugin - Tuner Pro KWP71 plug-in
pcmhacking.net - View topic - Motronic Real-time NVRAM module

MOATES OSTRICH 2.0 EPROM EMULATOR by Moates from only £201.80 | Tegiwa Imports

I will update this first post with links to options as they come up
 

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Well, it depends on the current ECU (or what does it support), as I recall at least one of your 33s has a non-factory one.
With the factory ML4.1 ECU there's no support for dizzy-less operation, but you can still have the hot film type MAF.
But replacing the vane type AFM with MAF in itself won't bring any spectacular results.
By modifying the fuel (and ignition) map at the high end may gives you a few extra HPs
(due to the lower air restriction and the higher volumetric efficiency).
 

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Discussion Starter #5
talking about my standard 16v, i was looking to get rid of the barn door and go dizzy less, how come you cant go coil pack, the ecu is self learning up to an extent and able to adjust within a certain amount.

talking about my omex 500 16v i was looking at going dizzy less but worried about plug types and wasted spark reverse discharge and damage to plugs
 

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Well, in case of the standard 16V there is only one ignition trigger channel is available, since it is designed as a single coil system. In order to use a coil pack and get rid of the mechanical HT distribution at least two independent ignition trigger channels would be required. With two channels a "waste spark" type coil pack can be used, like on the late 1.7 8V engines or on the 145/146 1.6 and 1.7 16V engines. (with four separate triggering channels you could address all cylinders individually, and every cylinder can have it's own coil) So this is not related to the self learning function, it's more like a design limitation.

In theory the reversed current that flows through one of the paired spark plugs would reverse the electrode wear.
(instead of the center electrode the surface of the ground electrode should wear off)
In practice I've used to check this phenomenon on my late 1.7 8V which was also equipped with coil pack, and I found nothing extraordinary during the service life of the plugs, the ground and center electrodes were looked normal when I compared the relevant spark plug pairs. IMHO there's nothing to worry about.
 

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Discussion Starter #7
is there a way to convert 1 ignition trigger channel to 4, using the cps to determine tdc engine position to differentiate which plug needs the spark?

how easy to transfer over the 145/6 setup onto a 33 16v and is it worth it?

on the 8v they use different plug types platinum / iridium, maybe because of the reverse discharge
the 16v use a different type of plug and don't like other types
the omex uses 2 ignition trigger channel, so a wasted spark coil pack could be used but worried about the above.
 

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is there a way to convert 1 ignition trigger channel to 4, using the cps to determine tdc engine position to differentiate which plug needs the spark?
This would require to split the CPS signal between the existing ECU and an external ignition signal de-multiplexer circuit. In theory this would be a de-multiplexer circuit that should contain a voltage level detector which resets a two bit incremental counter, and a driver stage towards the coils. I don't think this kind of circuit is readily available on the market, since this type of conversion/approach not too common.

how easy to transfer over the 145/6 setup onto a 33 16v and is it worth it?
90% of the parts are bolt-on compatible, but the wire loom lengths are different. (the ECU and the O2 sensor from the 145/6 16V are also needed) Some fiddling will be necessary around the fuel pump power supply to match the existing wiring with the new loom, and there might be other unpleasant surprises.
I think the throttle position sensor from the 145/6 can't be put directly in the place of the 33's throttle position SW.
The 145/6s are also equipped with an extra position sensor for one of the camshafts, this is needed for the phased injection (not all four, just two injectors will be fired at once). I'm a bit unsure about the trigger ring tooth count on the flywheel, which may be different from the ones installed on 33s. Sorry this was a long time ago...
Regarding the "worth it" part... beside the part costs this will require a lot of work, and the new configuration won't increase the engine output, just some more up to date parts were added.
So from a purely economic point of view I don't think it is worth the effort.

IMHO the main thing behind the iridium plugs is the longer service life, because changing the plugs is a pain in the @ss on the 16V engines :)
 

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Discussion Starter #9
With the factory ML4.1 ECU there's no support for dizzy-less operation, but you can still have the hot film type MAF.
But replacing the vane type AFM with MAF in itself won't bring any spectacular results.
Thanks for your reply :)
ok, so this i am interested in, just to get rid of the barn door, is there a way to adjust idle mixture, like on the barn door afm?
 

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In case of MAFs there's no provision for adjustments.
But... inserting a thermally compensated, adjustable precision amplifier circuitry between the MAF output and the ECU input it will be possible to alter the signal. This is true for those MAFs that have analogue output.
The more recent units have a "digital", these require a frequency to voltage converter in order to work with the ML4.1 ECU.
 

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Discussion Starter #11
any kits, links, diy tutorials?
the idle mixture screw just sends a steady voltage that is adjustable to set the mixture though...
 

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Not that I'm aware of, usually kits are include ECU and other stuff too and also the manual.

I guess you'll need to fabricate an adapter connector between the AFM connector and the new MAF.
A GND and an ignition activated +12V supply needs to be wired to the MAF connector.
There may be a difference in the air temperature signaling characteristics between the AFM and MAF.

In the new arrangement the (analogue !) MAF will provide the 0..5V flow signal without the need the 5V feed from the ECU. In the existing setup the ECU sends 5V to barn door and CO pots plus to the air temp sensor NTC.
This 5V won't be needed for the MAF, but it may work if a new pot (maybe a linear 5kOhm one will do) is connected between the AFM connector pin#1 and 4 if I'm correct.
 

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Discussion Starter #13
I'm surprised no one else has done this, or rather finished it
 

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Good catch ! (y)

The description doesn't say too much about the installation, and as I saw the air temperature sensor/signalling was not mentioned at all.
 

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Discussion Starter #16 (Edited)
Universal MAF Kit 3.0-A | (splitsec.com) as well
air temp is part of the MAF, what i dont see is the pot for idle mixture

i came across this as well,
What the stock 75 TS Motronic can and cannot do. | Page 17 | Alfa Romeo Forums (alfabb.com)
a really good read, learnt a lot, eg s30 connector switches on the fly. i run my 33 16v non cat non lambda car in 97 ron non cat mode but use 95 ron fuel, iv'e not heard any pinking, would i better setting the s30 to 95 ron no cat?
i remember that, but it went dead :(
i did manage to find a .bin file but no .xdf file :(
Alfa Original ECU Files – Chiptuning.pw

The Ultimate BMW MAF conversion (millerperformancecars.com)

looking at bmw and porche forums now
 

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air temp is part of the MAF, what i dont see is the pot for idle mixture
I'm aware that :) but your ECU will need the air temperature signal, which is currently comes from the AFM, and that is need to be rewired from the MAF,
otherwise the ECU will see -50*C incoming temperature.

I think the pot part needs to be hand-wired, because this is mostly replaced by the electronic mapping.
 

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Discussion Starter #18
i would have thought that the MAF temp signal is just wired to the ECU straight...
check out that thread, festy did a lot of work and lots of info in there but nothing from him since :(
other options are MAP conversion...
 

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When reading this thread I was exactly thinking about SpitSecond. 🙂

There are multiple possibilities.
The AFM to MAF (or MAP) can be programed to tailor it to what the engine needs. Also different sized injectors can be taken in account.
But to get it completely right some mapping of the original ECU('s) will be still needed, mostly regarding ignition mapping I think.

About splitting the iginition signal:
on the EZK iginition ECU from the VOLVO 740 Turbo the signal can be split in two so you can use a wasted spark DIS coil.
 
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