Another 3B to ABY conversion (Successfully)

[Carles20vt]

Well, I have done one of the major upgrades to my S2 3B from 1992. I have installed a AAN ECU with TFSI red coils with no problems.



I will explain a little my experience to encourage someone that want to do it

I started to make an Excel sheet to make the conversion pins but I have many questions about Clima and others. Searching a little at forum I seen that it’s done by S2Central. My pin assignations are well and I solved my questions with this Excel file. So finally I have been guided with these proved info: S2Central 3B to ABY conversion.

I used these coils and loom to do it: Coils and harness 3B to ABY


I not made a pin change, I made a ECU pin converter. More work yeach but I’m a nerd



When I fitted the new TFSI red coils I need to drop the rubber and cut 1-2mm the plastic base to fit at 3B rocker cover.

Engine started at first key so I was so happy. ^_^

I find some differences from 3B ignition to ABY/AAN. First it’s more smooth, sounds better and… The engine feels to have more power/torque at low/mid RPM. It’s another car, more nervous and responsive. I’m very happy. (My ignition dizzy are new and with metallic gearwheel, good wires… so it was not failing).

I have some moods to do. I want to put AAN cam cover. Why? Here we have very restrictive vehicle inspection programs so I want to see my engine looks stock. I like not justify to an ignorant inspector what it is, why, etc…

Another mod to do is put ABY fuel rail with stock 4bar fuel regulator, stock AAN/ABY injectors. It will do soon as I have a flexible fuel line and regulator clip that I don’t have yet. The have all rest of needed parts. I do it to match 100% ECU fuel rates and improve fuel economy (4 holes vs one).

So… Questions!!:

Could put AAN cam cover with stock throttlebody and admission tube? It looks that tube will not fit with these cam cover…

Could TFSI red coils will dead soon if I don’t change DWELL value at ECU? Or are these more tolerant at original DWELL value?

Thanks in advance guys

[vism]

Could you build another of those adapters?

[Carles20vt]

Could you build another of those adapters?

I could, but need a broken ECU (BMW, Alfa, and others have T55 connector too) and cut car harness with T55 female connector.

[igor136]

Do you have same boost? Mine is 0.2 bar lower with tfsi coils

[Carles20vt]

Another 3B to ABY conversion (Successfully)

Have you stock software at 3B and ABY/AAN ecus before compare it? What setup do you have?

Yes I have same or similar boost. (Now I have overboost)

[UrS4boy]

I think it would have been way easier to just swap the necessary pins at the ECU connector than build that "adapter".

Keep the 3B cam cover. Otherwise you will need an ABY or ADU cover.

The Dwell change isn't 100% necessary unless you plan on tracking the car and/or sustaining high RPMs for extended periods of time = heats up the coilpacks and kills them (partly due to the 4 ms OE dwell vs 2.5 ms revised dwell).

[VagOrBust]

Nicely done!
Now chiptune that AAN ecu and you'll have permanent overboost!

[SteveH]

Nice work!

I moved from 3B to ABY/AAN in a series of steps.

Pin swap and ABY ECU - Major neck and back ache after hours spent in the footwell fiddlin' with pins! Your connector means you can do it on the bench. Dizzy was still used for the hall sensor.
TFSI coil conversion and machined 7A cam cover
Dizzy deleted when I moved to an ABY head and cam hall sensor

It's been exceptionally reliable since and I don't have the worry of spark hop on the dizzy.

[DeS]

Also interested in this adapter

[gmac78]

Well done!!

I really must crack on with this myself! Not looking forward to hanging out in the footwell for hour after hour, your idea looks a lot less painful on the back!!

Interesting to hear how much smoother it runs after the upgrade, looking forward to it.

Cheers

[ralleyquattro]

I wonder where VEMS get their 55 pin connector, would be perfect for such adapter, need to do this on my 3B

[Kieron20V]

Cheap source for 55pin connectors. I have an ecu from a bmw 316 I think it is, cost me a tenner delivered on eBay. Will be using it to make an adaptor harness for mine.

Loads of bmws from late 80s and 90s use them, and some volvos too.

Sent from apollo 13 using tapatalk

[Carles20vt]

I think it would have been way easier to just swap the necessary pins at the ECU connector than build that "adapter".

Keep the 3B cam cover. Otherwise you will need an ABY or ADU cover.

The Dwell change isn't 100% necessary unless you plan on tracking the car and/or sustaining high RPMs for extended periods of time = heats up the coilpacks and kills them (partly due to the 4 ms OE dwell vs 2.5 ms revised dwell).

Thanks for your reply

Yes, it took to me many time to do, check, check and check again hehehe. The advantage is that is more comfortable do it on a table than on the floor.

When you say ABY/ADU cover, is the piece that covers the coils? Or other part?

Okey!, thanks for info. Really I use the car for all... It’s my only car and my illusion over child. But I don’t want to use only it for abuse at track days etc. So maybe I won’t worry about it. Only problem would be the very hot days at summer at my country.

Nicely done!

Now chiptune that AAN ecu and you'll have permanent overboost!

I’m trying to buy a ECU from friend with some sweets on it!!!

Nice work!

I moved from 3B to ABY/AAN in a series of steps.

Pin swap and ABY ECU - Major neck and back ache after hours spent in the footwell fiddlin' with pins! Your connector means you can do it on the bench. Dizzy was still used for the hall sensor.

TFSI coil conversion and machined 7A cam cover.

Dizzy deleted when I moved to an ABY head and cam hall sensor

It's been exceptionally reliable since and I don't have the worry of spark hop on the dizzy.

Thanks Steve! Many days/hours of schematics and soldering iron only hehehe.

Yes, it was the principal purpose of do the connector, and I was not 100% sure that all car functions will be running after it if I make a mistake or something. So I need to quick rollup if something is wrong.

Any improvement when changed to ABY head? If my memory is not bad it would be the same, except for dizzy of course…

I changed the dizzy or distributor entirely when I bought the car. It was with a broke plastic tooth gear and it will fail soon if broke another. Now have a metal gear. Until it I have no problems but the spark hop loose spark quality how you know…

You could have a nice engine, any pic?

Also interested in this adapter

I could made some and send it hehehe

Well done!!
I really must crack on with this myself! Not looking forward to hanging out in the footwell for hour after hour, your idea looks a lot less painful on the back!!

Interesting to hear how much smoother it runs after the upgrade, looking forward to it.
Cheers

Thanks Gmac How I explained upper of this reply it was done to don’t hurt my back. hehehe

Yup, I could feel it. Go to 3B to ABY with TFSI coils is a double upgrade… better than stock ABY/AAN spark so…

I wonder where VEMS get their 55 pin connector, would be perfect for such adapter, need to do this on my 3B

Yup, nice if you don’t want to kill and old random motronic T55.

Cheap source for 55pin connectors. I have an ecu from a bmw 316 I think it is, cost me a tenner delivered on eBay. Will be using it to make an adaptor harness for mine.

Loads of bmws from late 80s and 90s use them, and some volvos too.

Sent from apollo 13 using tapatalk

Exactly, and don’t forget to cut de female T55 connector from these car from scrap.

[Bowie69]

Are these them?

http://www.simtekuk.co.uk/product.ph.../?k=:::1618731

http://www.simtekuk.co.uk/product.ph.../?k=:::1618735

[Carles20vt]

Are these them?

http://www.simtekuk.co.uk/product.ph.../?k=:::1618731

http://www.simtekuk.co.uk/product.ph.../?k=:::1618735

Yes, they are!

I also found these:

Male/ECU Side

Female/Harness Side