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Discussion Starter #1
I was thinking of asking these questions on BradGTV's "Twinspark turbo using motronic?" thread, but since I'm not interested in a turbo, felt it best to start my own.

I'll admit I've asked many of these questions in sundry and various places, but will try to ask them all at once:

On my 75 TS I'd like to include slightly hotter cams, the inlet one retaining the VVT* (see below), slightly higher compression pistons (10.2:1)*****, individual throttle bodies** (most likely from a Spica, combined with the stock inlet manifold), and I'd like to retain the Motronic***.

I'd like any input regarding if the TS Motronic Squadra chip would be a good investment for this project.

I'll throw in here that if I could get 165HP at the (engine) flywheel along with better low end grunt, I'd be happy. Not at all looking for an engine which makes most of its HP at the upper RPM range. I want an engine in my Alfetta GT that can run errands and what I'll term be a bit more fitting for what I consider a gran turismo should be.

I've said this a million times (+/-) that it must idle smoothly and there must be a provision that bumps the RPM up (roughly) 500 RPM when the A/C comes on - so no more braking and keeping the revs over 1,000 every time I come to a stop, or just slow down when the A/C is running.

*VVT: Apparently Wes Ingram can reverse engineer the stock cams to come on later, like 3,600 to 4,000. Unfortunately I want lower end grunt so perhaps that won't benefit my needs - though if someone could do a (professional - welded and hardened) job of reprofiling the inlet cam to allow for more low end torque, that would be ideal. If not, then a non-VVT cam that can do the job will be fine. Obviously I need a more aggressive (perhaps not the correct term) exhaust cam.

**Individual throttle bodies: I realize that if I go ahead with this, it might well be a deal breaker for using the Motronic. I have no idea if the Motronic could handle the manifold pressure sensor, throttle position sensor, etc. but assume it could. I have to admit I really, really like 69Alfa/David Munro's Suziki (believe that's correct) throttle bodies on his TS.

Since there would no longer be a means of using the AFM, is it possible that an add on control module could then use a wideband sensor - or is this sensor too intertwined with all of the other sensors?

***Motronic: The four main reasons I don't want to use an aftermarket system are (1) I do not want to make a custom wiring loom, period. Though I'd be game for fabricating an add on one. (2) Cost. (3) Complexity. (4) Reliability - meaning I'd never be sure if I had it set up right or not and I don't want to have to worry every time I venture far from home.

*****Compression: Does anyone know what the compression bump is for switching to Nord rods (I have more than a few sets of them)? And does the head have to be relieved the 1 mm? I'd think not.

If anyone can point me in the right direction on any of these items I will be needing and of course comment on the feasibility of staying with the Motronic, I'd really appreciate it.

Last time I asked about TS cams a fellow ABBer sent me a large list of cam profiles and asked which one do I want. Unfortunately I need to have my hand held as I venture into mostly unknown territory. I envy you who are fully versed on electronics but have the knowledge to suggest something like...."In your case get a throttle position sensor from (a particular year and model car) but switch the green wire to...or some such information.

I'd sure like to quit daydreaming over the TS project and get on with it, but I need to have all of the questions and suppliers nailed down before I begin.
 

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About the ECU.

You can put megasquirt PNP to Motronic.



Almost the same is Kdfi, based on megasquirt.

k-data.org

Staying whith Motronic and run whith ITB´s, you need a piggyback ecu and another AFM or a specific chip and the AFM problem again.



DIYautotune gives you support to make the conversion to the ml4.1 for sure.

 

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I will be doing something very similar early next year. There is no reason that you can't use the original AFM. I have a BBR powerchip for my Motronic too!

Take a long look at the set-up of the ITBs/TPS/Motronic system on the 16V Boxer engine. However, I would not run the fuel pressure regulator off one port, I would run four vacumn lines into one plenum (also supplied by the idle speed actuator). You could use the idle speed adjustment do-hickey off the Spica as a junction port (of course without the fat O-ring). The volume of the supply hose from the ISA should smooth out the pulsations from the ITBs.

Bob's yer uncle!

BTW: I achieved 165 bhp on a stock T-S engine with a port job, 45mm carbs and some pipes.
 

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Discussion Starter #4
Luis, thanks for this information. Was the stock ECU a Motronic? If so I find it interesting that the other one uses the same connection. I gather the guy had it preprogramed?

I sure don't understand what it was that he substituted for the AFM. He talked about four or five pins, but I wasn't able to pick up what he was saying about it. It almost seemed as if 'why would anyone have an AFM on their car'?

What exactly was supplying the engine with the correct air/fuel mixture?

Clayton, I really don't find the AFM's very attractive. I'd like to not have to install the long 'air box' going into the intake manifold. I really like the look of TS engine bays that aren't cluttered, but in my case I want to stick with fuel injection.

If you don't mind, could you ship over a - "Take a long look at the set-up of the ITBs/TPS/Motronic system on the 16V Boxer engine." I promise to return it after I'm through with it. Except for a few 'exception Alfa's' the latest Alfa's here are '95 Spiders.

It does sound as if what I want to do is possible - though I need to know more about the system you're suggesting, Luis.
 

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If you don't mind, could you ship over a - "Take a long look at the set-up of the ITBs/TPS/Motronic system on the 16V Boxer engine." I promise to return it after I'm through with it. Except for a few 'exception Alfa's' the latest Alfa's here are '95 Spiders.
It isn't a book. I meant to have a look at how Motronic is set up on the car... But then I forgot that you never got that model in the states.

Ask the boys on the boxer forum for some pictures and info.
 

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t-spark

Biba,

I am curious about the information you are getting. I have had a similar project in mind.

However, like Clayton and many others, so far on a t-spark I've had pretty good success just switching to carbs and a distributor. I re-profiled the cams and kept the electro-mechanical unit using a simple rpm trigger to activate it. There are a number of simple ways to kick up your rpm at idle when the AC is on. Why use the Motronic if it seems like too much trouble?

I suppose, here in California, you might have a better chance of getting through the smog check process with a computerized system, both for looks and what the sniffer picks up. Good luck.
 

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Luis, thanks for this information. Was the stock ECU a Motronic? If so I find it interesting that the other one uses the same connection. I gather the guy had it preprogramed?

I sure don't understand what it was that he substituted for the AFM. He talked about four or five pins, but I wasn't able to pick up what he was saying about it. It almost seemed as if 'why would anyone have an AFM on their car'?

What exactly was supplying the engine with the correct air/fuel mixture?

Clayton, I really don't find the AFM's very attractive. I'd like to not have to install the long 'air box' going into the intake manifold. I really like the look of TS engine bays that aren't cluttered, but in my case I want to stick with fuel injection.

If you don't mind, could you ship over a - "Take a long look at the set-up of the ITBs/TPS/Motronic system on the 16V Boxer engine." I promise to return it after I'm through with it. Except for a few 'exception Alfa's' the latest Alfa's here are '95 Spiders.

It does sound as if what I want to do is possible - though I need to know more about the system you're suggesting, Luis.

The Twin Spark have Motronic ML 4.1, it´s a 35 pin Bosch ECU.

Megasquirt it´s a DIY programmable ECU, you can purchase a PNP kit that basically it´s a Programmable ECU whith the Pinout you need to work with the Stock wiring loom.

If you have a Ignition map you can get the Injection map whith a wide range lambda sensor, a computer and a few rides.

Whith this ECU you can run the stock components, run ITB´s and go for distributorless ignition whith a little modifications when you want.

You don´t need the AFM anymore, it´s all based on manifold air pressure versus rpm or Alpha-n (throttle position versus rpm).

I know that DIYautotune gives support and can help you to get your car run, just mail them whith what you want to do and they give you and answer whith the configuration you need.

About the Boxer 16v ITB´s running on motronic, it´s silly as if you put ITB´s on the intake runners, throw away the stock butterfly and all the system (plenum, AFM...) stays stock.
 

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Nice option

This DIYautotune seems like a great option. It's tough to beat a factory wiring harness for reliability plus you could easily put the factory motronic ecu back if you are having issues. Wish I found this earlier.

Daron
 

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Discussion Starter #9
Dan, having fuel injection is one of the main priorities of the TS project. I have DCOE's on my '75 Alfetta GT, like their simplicity (by comparison) but I want precisely metered fuel, and the smoothness of FI. I've not found anyone to come forward to offer specific suggestions as to how to make my DCOE's increase 500 rpm when the A/C is switched on - though several have said how easy it is.

Luis, thanks for all of this good info. I have an email into DIYautotune and am curious as to what they'll suggest, along with cost.

Where does one get the injection map for a TS? Also, what is meant with 'rides', as in, "...a computer and a few rides."

Things are looking up.

The photos are of David Munro's/69Alfa, Suzuki throttle bodies. The second one is with it sitting on top of the TS inlet manifold. It sure looks cool to me.
 

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Discussion Starter #10
I received a questionnaire back from DIYAutoTune and one of the questions was (and here I thought I was the only person that gave a danm about idle): "Does this engine have a fast idle valve (IAC)? If so, how many wires are connected to it? Do you know if it is an on/off, pulse width modulated, thermal, or stepper type?"

How would you have answered these questions? And if it has one of those things, where is it located and how many wires are connected to it?
 

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The fast idle valve is the cylindrical thing that hangs off the main plenum on the twinspark. If I remember correctly, it is a 2 wire unit. Do an internet search for Motronic ML4.1 for the particulars on how it is actuated.

Regards,
Lawrence
 

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Discussion Starter #13
Another question I (we?) need to answer for Matt at DIYAutoTune: He needs to know everything the ECU controls. I have the TS shop manual, do I just go down the list and try to include everything that looks like it goes to a sensor? However, I have no idea, for instance, if '20. Fan control cable' simply goes to the fuse box or to the ECU.

He says he has no knowledge of the European Motronic. Is it much different than the unit in US Series 4 Spiders?

Is there a list of what all connects to the 35 pins?
 

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Discussion Starter #14
Never mind, I'd forgotten I had a really nice Motronic colored wiring diagram that iachella sent me which of course includes all of the sensors, etc.
 

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There's a ton of information on the Megasquirt sites. Between the manuals and forums (including archives), you should be able to come up with the answers to DIY's questions. They're building the ECU to your requirements so you have to plan out the full conversion ahead of time.

I suspect keeping the stock ECU is more trouble than its worth if you're looking to go to ITBs. Also, Megasquirt is far from a plug & play system. I had to buy an oscilloscope to troubleshoot some of the signals on mine. Make no mistake - this is a lot of work.
 

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motronic?

Great point from Logwin, updating the Motronic or a completely new programmable system can be a lot of work. Interesting and fun for sure though! Biba, I am installing AC in my Jr.Z and I will be installing the very kind of idle adjustment switch we're discussing. I've done it before on another project with good results. I'm thinking of getting a signal form the relay from the AC. Then installing the switch/solenoid to "push" anywhere I want to give the idle adjustment an nudge (a few 100 rpm at idle with the AC on). Quite simple and easy to install. These switches go by at least two names: idle up switch or step up solenoid. The last one I bought was only about $40. D
 

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A few Schematics of the 75 ml4.1, can´t get the ECU pinout in easiest way but it has almost the same pinout and sensor than other 35pin Motronic used on BMW cars.

A1 Battery
A8a Ignition distributor A
A8b Ignition distributor B
A12 Spark plugs
S12a Petrol pump relay
S12b Motronic relay.
G131 Ground upper cover.
S7 Coolant temperature sensor.
M15 Emision control solenoid valve.
S10 Lambda probe.
S30 Motronic swithc connector.
T2 Diagnosis.
T1 Alfa tester.
S29 Idle adjusting actuator.
S13 Timing sensor.
S6 Aceleration Throtle switch.
S5 AirFlowMeter.
S3 Injector.

Wires have Color initials and section, like B1 it´s Black 1mm.

About S6, it´s a switch not a potentiometer one, Motorcycle ITB´s have potentiometer, change the motorbike plug to the motronic one or viceversa and you are done.

About the Ignition MAP, searching Youtube i have found TS conversions, maybe they can share their maps, or even users on this forums whith TS conversions.
 

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Discussion Starter #18
(Most likely) out with Megasquirt and on to k-data.org (maybe - just emailed them). I just received this reply from DIYAutoTune: "It looks like you would need control over the fuel, ignition, PWM idle, and the variable cam relay. THat's not too hard to arrange. However, what we don't have is a 35 pin ECU plug. I'll email you if we add this to our lineup, but at the moment, you'd have to cut the plug out of a junkyard ECU and solder one of our pigtail harnesses to that. Would an approach like that meet your needs?"

No.

I'm really considering gambling with the Squadra chip, making my fairly mild compression and cam modifications, along with using 2002-03 Suzuki motorcycle throttle bodies and 'larger' injectors (would definitely need help on that, as well as the cams).

The really big questions are if it is possible to use a Lambda sensor for fuel/air mixture rather than the AFM. If a pigtail arrangement would work, then I'm fine with that.

The 75's TS is noted for good torque and all I'd like to do is increase that 'somewhat' along with improving overall response. I'll make no bones about it, the intake arrangement is 75% aesthetics - I hate the looks of AFM's and all the myriad hoses, both large and small, needed for it.
 

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Biba:

Just saw this post. Two things to consider with the existing Motronic:

1) It must have an AFM signal
2) The TPS is a switch, not a sensor

For the AFM, there are discussions about a MAF (Manifold Air Flow) like an AFM without the flap. You replace the AFM with the MAF, but you have an extra box to re-map the signal because what comes out of the MAF isn't quite the same as the AFM. It's a long thread that I participated in as well as Craig. It's because of that discussion that I abandoned that idea and went with a stand alone ECU.

For the TPS, if you have Jim make your Spica TBs on the intake manifold be sure to tell him you will be using a switch. He will by default install a GM sensor, as he likes that better. I tried to have him use a Bosch as you could swap it for another Bosch in switch mode, but I didn't push that hard.

I understand looking into every available solution to come to the least amount of modifications. I had run through so many scenarios as well. In the end, the amount of work for most options turns out to almost as much as a stand alone system. As far as driveability, some of the systems have adaptive learning with a wide band 02 sensor that will map it for you. I'm also going to keep the robust Motronic harness and make a "patch cable". I have another thread going on that. I found some interesting things when I started playing with the Bosch 35pin connector and a pigtail from a junk yard. If you want me to elaborate, let me know.

I think you could chip it with Spica TBs and a TPSwitch attached. Maybe hide the AFM in front of the radiator with a cone filter on it and pipe the air back through the radiator support air hole. Also, a bigger AFM from a big BMW is available and not too much work, I understand.
 

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Discussion Starter #20
Stefano, do you have a thread on your entire 'plan of attack'? If not, why not?

Also, did you check out the video that Luis included? Somehow a BMW, pretty sure that's what it is, is running without an AFM or MAF. I've dug out my "Bosch Fuel Injection & Engine Management" book. I'd read through the Motronic part after I first got it, and everything went right over my head. Having done a major detailing on a client's '88 Quad in which I removed most all of the L-tronic stuff from the engine bay so I could detail them out, I did get a bit of a learning experience - or more accurately a somewhat familiarity regarding the different parts of the fuel injection set-up - including sending the injectors off to Greg Gordon for cleaning and reassembling with hoses on the plated fuel rail.

The read of the book this time is making more sense. This is a by the book book, and there is nothing about installing aftermarket systems. However, it sure seems as if the lambda sensor - and I'd assume especially the later ones - sure gives the ECU a lot of information. This is why I emailed k-data.org, though I'm not too hopeful since all of their ECU's are either for BMW's or VW's.

If there is absolutely no other way to avoid all of the crap that has to attach to the head, just to accommodate the AFM, so be it...but I won't be happy with it.

Of course carbs take care of that problem, but to me it is a shame not to get all of the benefits of fuel injection.
 
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