[PSIG]

I have a 1981 Rabbit Pickup that I am attempting the same Fuel Only conversion on. … I am keen to learn about using the distributor for the ignition trigger.

In fuel-only conversion, the ignition portion is simply ignored.

If one is using just the output from the destributor hall sensor to trigger ignition on the speeduino , how do you address ignition timing advance (mechanical and vacuum).

In fuel-only conversion, the stock ignition operates dwell timing and advance independently. Only the distributor pulses are shared in order for Speeduino to sense rpm, calculate, and time fuel events. Addressing ignition timing advance is not fuel-only, and is a fuel & ignition conversion. Choose your path so you do not become confused by the different options. We are assuming by your statement that it is to be fuel-only.

Every choice is a set of compromises, and the lack of ignition control can be very limiting unless it is a short intermediate step to a full conversion. Choose wisely. While it may appear that fuel-only is simpler to convert, in other ways a full conversion allows the operation and tuning to be simpler and more effective as they are coordinated. Fuel and spark work as a team to extract energy, and controlling only one limits the capabilities. Still, some lesser gains can be made, limited by the one you do not control. Make your informed choices and set your plan.

Does one lockout the advance in the distributor and let speeduino handle the advance or …

Again, in a fuel-only conversion, the stock system operates independently without other change. Commonly, these are "piggyback" conversions, allowing the original ECM to handle everything but fuel injectors. Speeduino simply watches the distributor signal for fuel functions.

Yes, the injection timing will shift with the independent ignition pulses, but that is less important than if you were to shift timing randomly. Either allow injection to shift timing, or take control of ignition timing. The goals of your conversion will help dictate which path is better. For further discussion, please start your own threads, so the OP's thread is not hijacked further.

[zwelsh91]

Thanks for the explanation PSIG. Looks like I do not have enough of a grasp on the terminology of the different configurations yet. Sorry to have "hijacked" this thread. I'll do some more searching in the manual (Which is very vague about it's interface with distributors ) and on the forum for more information. Thank You Again!

Cheers to soultron on his project. I'll be keeping an eye on it. would be pretty neat to see it up and running.

[soultron]

Thanks for the explanation PSIG. Looks like I do not have enough of a grasp on the terminology of the different configurations yet. Sorry to have "hijacked" this thread. I'll do some more searching in the manual (Which is very vague about it's interface with distributors ) and on the forum for more information. Thank You Again!

Cheers to soultron on his project. I'll be keeping an eye on it. would be pretty neat to see it up and running.

Sorry for the delayed feedback, no worries on the thread hijack, there's not many for this platform so I understand. I'll do a condensed explanation once I'm done for future folks.
But it would seem my coil and possibly my module aren't functioning (maybe). Or I did something wrong but either way, I was only going with the distributor until I could make my own trigger wheel.
Since I would have to spend money to replace the distributor parts anyway I ended up going with one from Tech 53.

I made things a little more complicated by swapping to a serpentine belt but so far its not still pretty straightforward. I have to decide on trigger angle and make a sensor bracket.
I'm likely going to be happier with it in the long run.
Here's one of the other threads I've found :
http://speeduino.com/forum/viewtopic.ph ... d17ddbdae0

[soultron]

Nearly assembly. All that's left is the trigger wheel and sensor I mocked up on another block.



I'm very close to cranking. Everything tests great
Att thinks this site is phishing so it's difficult to post sometimes. Very annoying.

[zwelsh91]

Looking good man! I fired mine up last night for the first time. Best feeling in the whole world when it all comes together and works.

[soultron]

Looking good man! I fired mine up last night for the first time. Best feeling in the whole world when it all comes together and works.

I'm working on getting the base map together for the first start. It's really exciting.

[zwelsh91]

I am working my way through my base tune as well. Got my truck fired up and idling fairly nicely but I do not have my O2 sensor installed so that is about all the tuning I can do at this point. Without feedback of the AFR, anything I do is just shooting from the hip in the dark. It took me a couple times to get the trigger offset figured out and to stabilize the timing. All is good now. I ended up registering my copy of tuner studio and using the table generators to make my own ve and afr based on stock VW 1700 gas specs. I suspect that the Ignition timing table is going to be my biggest hurdle. I generated a table using the table generator in the megasquirt manual but it was way too far advanced at idle and everywhere else. I ended up having to scale back the all the values quite a bit.

[soultron]

I gave the car a test start this evening. Tried my best to set up a base map but I'm likely missing something. It cranks well and starts to fire up but doesn't stay running for longer than 10 seconds. It was a little late and I don't want to bother my neighbors so tomorrow I'll check all the settings again and maybe add fuel. It's been quite a process but I feel confident that it's going to work quite well.

[zwelsh91]

Congratulations! hearing your project fire the first time is the best, even if it doesn't run quite right, at least you are doing something right if you can get that far.

Where are you pulling your map from? I abandoned the ports on the throttle body ( I just do not have the patience to try and find out which ones are ported and which ones are manifold vacuum. I ended up hooking my map line to the extra port on the feed to my brake booster (not ideal, I know, but I have not seen vacuum signal change much at idle while I mash the brakes repeatedly). The reason I ask is that I see a vacuum line attached to the front port on your throttle body in one of your pictures. That particular port is where I started and it ended up being ported so I could only seem to get 35-40 kpa with the throttle closed and basically 100kpa at any throttle position than that (talk about making tuning hard).

What did you end up deciding on for trigger?

[soultron]

Congratulations! hearing your project fire the first time is the best, even if it doesn't run quite right, at least you are doing something right if you can get that far.

Where are you pulling your map from? I abandoned the ports on the throttle body ( I just do not have the patience to try and find out which ones are ported and which ones are manifold vacuum. I ended up hooking my map line to the extra port on the feed to my brake booster (not ideal, I know, but I have not seen vacuum signal change much at idle while I mash the brakes repeatedly). The reason I ask is that I see a vacuum line attached to the front port on your throttle body in one of your pictures. That particular port is where I started and it ended up being ported so I could only seem to get 35-40 kpa with the throttle closed and basically 100kpa at any throttle position than that (talk about making tuning hard).

What did you end up deciding on for trigger?

I'll keep the vacuum line in mind. I might have to take it off to figure out if it's manifold but it looks like it's behind the blades. My throttle body is from a later Audi. It already had a spot for the throttle positioning sensor.
I'm using a crank pulley and 36-1 but I'm researching crank seal set up I've seen. I haven't got all the info (probably something I've missed) but it's from a later block.
One issue I hadn't thought of when I did the ce2 conversion: the starter switch. I had everything hooked up to my own relays before but the ce2 fuse box gave me an opportunity to clean up the wiring and simplify things. However I forgot the Volkswagen starter switch has to be turned all the way to the off position each time you try to start it. The plan is to set up a starter button sometime this week. I'll still turn on the car and accessories with the key but I'll have a button to turn the starter.