'87 505 GLS Fuel Injection System

[FONT=&quot]Hi everyone,[/FONT]
[FONT=&quot]I have an update! Stewart, I hope you're listening, I need a seasoned ZDJL expert on deck![/FONT]
[FONT=&quot]I've successfully built and installed the missing tooth wheel crankshaft wheel. The 505 is running and I am controlling both fuel AND spark![/FONT]
[FONT=&quot]I owe much of my design to an Australian friend of mine, Rob Swan, he built a similar system last year and is using it on his 505 ZDJL 851.y (the 851.y is the high compression Series 1 GTI ZDJL, my engine is the US spec 851.x with lower compression).[/FONT]
[FONT=&quot]Anyways, I noticed his timing map looks much like the one Stewart posted earlier on this thread, about 35 degrees of max centrifugal advance. Bizarrely enough, my US spec manual shows the maximum centrifugal advance to be only 25 degrees. Using his spark map, my engine performed beautifully with absolutely no knocking. Could this be why the USA ZDJLs were infamous for being more sluggish than their Renault counterparts. Massively retarded timing to meet some emission standard? I'm shocked, I can't imagine that retarding my timing 10 degrees would result in better performance, from what I understand power will flatline past a certain advance - sometimes before the knock limit, but I've never heard of 10 degrees of flat power and no knocking![/FONT]
[FONT=&quot]Here is a link to some pictures of my build, as well as my ZDJL 851.x spark advance table from the manual:[/FONT]
[FONT=&quot]https://goo.gl/photos/gZ13wHQKazLwqyVc9[/FONT]
[FONT=&quot]Bizarre.[/FONT]
[FONT=&quot]I will report economy improvements soon. Drive-ability and responsiveness has improved significantly with the better crank trigger installed. This car drives way better than the factory ZDJL did.[/FONT]
[FONT=&quot]Wade[/FONT]
 
I'm watching Wade! I can give you a close ignition map so you can tune mixture and a map which will go very close to perfect based on mathematics and geometry too. I'll get to it.
 
Base map and final estimate

ZDJ ign map.PNG Here you are. Light red is close to std curve and should be safe to set up fuel first. Dark is Ideal prediction. Use manifold pressure for the Y axis for fuel and ignition. At idle MAP say 45 50 55 at 700 to 1000 set at 13 to 15 deg. at rpm above for 50 to ) Map add 6 deg to the base map above and you should go close. Curves are for 100 Map, eg wide open throttle. Make sure the engine isn't pushing oil into the inlet while tuning as it throws the tune out the window. Cool stuff!
Would you like the Megasquirt prediction too?

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6700
</xAxis>
<yAxis name="kpaix" rows="12">
25.0
32.0
39.0
46.0
53.0
60.0
66.0
73.0
80.0
87.0
94.0
101.0
</yAxis>
<zValues cols="12" rows="12">
13.0 10.0 18.0 23.1 28.1 33.2 38.3 40.8 40.8 40.8 40.8 40.8
13.0 10.0 17.7 22.7 27.7 32.6 37.6 40.1 40.1 40.1 40.1 40.1
13.0 10.0 17.4 22.3 27.2 32.1 37.0 39.4 39.4 39.4 39.4 39.4
13.0 10.0 17.0 21.9 26.7 31.5 36.3 38.7 38.7 38.7 38.7 38.7
13.0 10.0 16.7 21.5 26.2 30.9 35.7 38.0 38.0 38.0 38.0 38.0
13.0 10.0 16.4 21.1 25.7 30.4 35.0 37.3 37.3 37.3 37.3 37.3
13.0 10.0 16.2 20.7 25.3 29.9 34.5 36.7 36.7 36.7 36.7 36.7
13.0 10.0 15.9 20.3 24.8 29.3 33.8 36.0 36.0 36.0 36.0 36.0
13.0 10.0 15.5 19.9 24.3 28.7 33.1 35.3 35.3 35.3 35.3 35.3
13.0 10.0 15.2 19.6 23.9 28.2 32.5 34.6 34.6 34.6 34.6 34.6
5.0 10.0 14.9 19.2 23.4 27.6 31.8 33.9 33.9 33.9 33.9 33.9
5.0 10.0 14.6 18.8 22.9 27.0 31.2 33.2 33.2 33.2 33.2 33.2
</zValues>
</table>
 
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Thanks Stewart!

So is that dark red curve the maximum performance curve that you found by experimentation on your own engine? Was this found on a dyno? Awesome information to have! I'm assuming you have the ZDJL 851y model that has the 9.9:1 compression ratio. The US model had an 8.8:1 ratio and had a reputation to be somewhat of a sluggish, noisy gashog... Funny, that sounds awful like the symptoms of retarded timing. Turns out, my lower compression engine came to life when I advanced the timing curve from it's factory max centrifugal advance of 24 degrees to the 32 degrees used on the GTI! (Thanks Robs for your GTI's table).
When I sent Robs a picture of my 505 851x low comp engine timing curve in the manual, we initially thought that his table had been corrupted it was so far off from mine!

It's no wonder that this engine was seemingly far less popular in the US than it is in Australia! Thanks Stewart for that optimized timing chart, I'm sure Robs will be excited to see that. As for me with the lower compression engine that is slightly different, it sounds like I may be able to experiment a little further with the timing (after fuel is set, of course). I may be able to push the advance further due to the lower compression. God, I'm adding so much advance to the factory curve that I'm almost worried my rotor will completely pass the intended spark plug lead before the coil fires! Well, I guess I can always twist it the old fashioned way and try to balance the phasing, right now I have it centered in it's slot. (God, is the engine bay hell to work in on the ZDJL, the 45 degree lil hemi pushrod in my 404 is like the grand canyon in comparison).

I guess my next step is to get my fuel map set, need some open road - or I may take it to a dyno shop. A guy tapped me on the shoulder in one of my classes today because he saw me fiddling with my TunerStudio. He was a guy probably in his late 30's who said he has done dozens of megasquirt builds. I may be able to link up with him and get some tips on the art of tuning!
The new megasquirt code has some great additional features. You can set up what is basically Proportional control for the spark timing at idle. This complements the PID controller for the PWM air valve and has given me a lot of idle stabilizing tools. All in all some cool stuff. You can even reroute the A/C compressor clutch wire to the MS unit, and then have the megasquirt activate the compressor after boosting the idle a few hundred milliseconds before clutching the compressor (granted, the current MS unit has open loop versions of both the air valve and the a/c idle up that probably work okay).

Whew, I wonder what some of the ZDJL guys in the USA "Peugeot of North America" will think of this! Although, I am not sure that they could just advance their timing by rotating the distributor without hitting some pinging.

I'll report back when I get some fuel tables dialed in!
 
By the way Wade the Peugeot ZDJ was pathetic when compared to The R25. Renault used the same valves cam and combustion chamber but had smaller inlet ports and a longer and hotter inlet manifold, tuned exhaust manifold plus the beautiful Renault engine management. They were very fast discrete touring cars here in Australia. 3 speed auto was my favourite .
 
Cool Wade. Good on you for jumping in with us! I have proven the programs I use as well, on 5 unusual to me, engine builds.The ideal timing is provided the engine is free of pinging.( I like to advance the cam timing on those 505 engines and have a 280 deg cam with 0.410" lift too).
I proved the data on a test rig I made for an XN2 I made EFI with wasted spark. Software said 150 lb ft at 4500 at X degrees , Provided the air fuel was 12.5 and the fuel didn't ping.
It did it too. 150 lb at 4500 rpm. N/A throttle bodies etc.
What we are doing here is a quite accurate guess at a peak mean curve. Essentially write your predicted map and start tuning fuel in a retarded state to the new map. In other words load the map and make it start 5 degrees retarded and tweek the idle degrees back up to the prediction while you tune. Have you got an Innovate or wideband 02 hooked in? We have no hope without that.
The fuel map is a real difficult thing to make with out an auto tune function and a Constant Inlet Temp and Coolant Temp. If you want a Volumetric prediction I can do that too. Great fun !
 
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Hi Stew,
Yes, I have a wideband O2 sensor hooked up that will help me dial in the VE bins. I currently have my desired AFR table set to provide economy in the cruising bins (just lean of stoich, maybe 15.3), and then a health rich mix as I approach WOT (12.5 to 13) bins. It seems idle does well around 13.7.
So, the next step is finding some open road where I can maintain a constant coolant and intake air temp as I cruise and tune the VE bins appropriately. First, I'll get an oil catch can to prevent any oil from making it's way to the intake. My engine doesn't ping at all so far, probably the lower compression ratio is helping with this.
Regards,
Wade
 
Wade,may I suggest making your air fuel ratio bins 12.5 in all bins until the ignition is sorted then
for VE over 80% , leave at 12.5 and say 13.5 for 70%. For cruise under 70% 14.5 if you can.Any leaner and the power drops off which becomes difficult to tune ignition with risk of lean misfire. The heads are very good at lean mixtures but the power difference between 14.5 and 12.5 is quite a lot. The engine loves 12.5 and becomes very smooth in torque delivery. They will idle at 14.5 and cruise at 14.5 no problem but it's getting the ignition point perfect at 12.5 is the key to fine tuning up to 14.5. Just thought I'd share what I have learnt with my Link G3. It has an auto tune for mixture but if the ignition isn't right it's a nightmare! What dwell time do you have on the coil, by the way?
I recall tuning in the ZDJ/L closed loop and reading 14.5 on all conditions apart from full throttle high load where the TPS had closed the full load switch. Even then it was 13.7 or close to that. I guess you could start there with the VE but the smoothness and extra power from 12.5 will surprise you. I find if the engine is making the best torque it can the economy isn't really compromised anyway. Just trim to 14.5 in areas like cruise and over run once you find the sweet spots in the engine!
 
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