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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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 Posted: Thu Apr 22, 2021 10:56 am Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Thanks guys, very clear. I suspect the idle screw is maxed out, will investigate. The TB seal is there and in good shape. One time I did not install it well and it produced a loud 'whistle '. I will get there in the end!
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'71 411 stationwagon |
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Sat Apr 24, 2021 8:24 am Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Checked the idle screw and it does make a difference, once I went clockwise a few turns, so it was indeed maxed out. I decided to tinker with the ignition timing just a bit, turning the distributor counter-clockwise and just a bit of that did increase the idle rpm quite a bit. I did this also because after I installed the properly functioning vacuum canister on the distributor and setting timing to factory spec + replacing the points and rotor, the car ran well, however:
- cold starts became MUCH harder (before they werd instantaneous, now it took maybe 5 to 7 attempts) and
- I could hear some engine knock at higher speeds like 50 MPH under load
Now I think turning the distributor counter-clockwise only adds more advance, not less. So that would worsen the knocking. Have to check with timing light.
The running characteristics, from just having set timing a bit different, are very pronounced. Car started better this morning, although still not as quick as before. Idle much higher, and now also big difference between in and out of gear, whereas before the timing change there was no difference at all (likely due to changed vacuum, which has affected the "throtthe pusher" that I had set at a certain point). Also, idle in neutral is 'uneven', staying high, then settling down, bit unpredictably. Before it was very even and always the same.
So I am starting to appreciate that minor adjustments and factors (like vacuum leaks) have major impacts on the tune (as others with actual experience have already commented) and there's actually a lot to this. Would probably really benefit from having an actual expert go over all the various aspects and check, set and tune it properly.
Still, it runs well and strong, so no immediate need to dig in much more. Will see what I can do, starting with timing light, dwell meter, vacuum meter and so on.
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raygreenwood
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Joined: November 24, 2008
Posts: 21507
Location: Oklahoma City
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| Posted: Sat Apr 24, 2021 11:59 am Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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| Cees Klumper wrote: |
Checked the idle screw and it does make a difference, once I went clockwise a few turns, so it was indeed maxed out. I decided to tinker with the ignition timing just a bit, turning the distributor counter-clockwise and just a bit of that did increase the idle rpm quite a bit. I did this also because after I installed the properly functioning vacuum canister on the distributor and setting timing to factory spec + replacing the points and rotor, the car ran well, however:
- cold starts became MUCH harder (before they werd instantaneous, now it took maybe 5 to 7 attempts) and
- I could hear some engine knock at higher speeds like 50 MPH under load
Now I think turning the distributor counter-clockwise only adds more advance, not less. So that would worsen the knocking. Have to check with timing light.
The running characteristics, from just having set timing a bit different, are very pronounced. Car started better this morning, although still not as quick as before. Idle much higher, and now also big difference between in and out of gear, whereas before the timing change there was no difference at all (likely due to changed vacuum, which has affected the "throtthe pusher" that I had set at a certain point). Also, idle in neutral is 'uneven', staying high, then settling down, bit unpredictably. Before it was very even and always the same.
So I am starting to appreciate that minor adjustments and factors (like vacuum leaks) have major impacts on the tune (as others with actual experience have already commented) and there's actually a lot to this. Would probably really benefit from having an actual expert go over all the various aspects and check, set and tune it properly.
Still, it runs well and strong, so no immediate need to dig in much more. Will see what I can do, starting with timing light, dwell meter, vacuum meter and so on. |
OK...some notes.....I know you are just experimenting so all is good...but just so you know....you cannot use the ignition timing to adjust idle speed...not ever and not even just a little bit.
The ignition timing setting for D-jet injected engines must be SPOT ON...set as factory.....unless you have a different than stock cam or you are doing some performance tuning or are counteracting for the installation of an electronic points replacement module.....and in all of those cases....you can only move timing a small amount and must usually correct fuel mixture at the MPS.
The problem the ignition timing tinkering causes...is that is a MAJOR, MAJOR change factor of engine vacuum signature. That causes changes to fuel mixture at the MPS...which changes everything.
To add to this.....you cannot just move ignition timing around at will....BECAUSE....the injection timing is slaved to the distributor and moves around with it. This changes how it is key to camshaft position for intake valve opening point. This is another of those MAJOR change factors to vacuum signature and fuel mixture.
But.....this is not saying that the testing and R&D you are doing is not excellent to do. It is.....just understand what it causes and controls...so you do not make changes on a whim.
In fact.....the correlation between vacuum signature and ignition timing....and vacuum signature and injection timing....and the effect of both of fuel mixture......is one of those things that is very hard to get D-jet owners to wrap their head around.
The distributor/ignition timing R&D you are doing or "could be" doing....is a major key to really getting some of the detail tuning for D-jet down.
Understand this.....the combined movement of ignition and injection timing by turning the distributor to timing positions different than the factory setting.....have a profound effect on the MPS and fuel mixture....and seeing this in REAL TIME can REALLY help you tune the system. Try these things:
1. Make sure your distributor is clean, oiled, advance operating perfectly and is tight with no slop in the points plates etc.
Make sure the trigger points for the EFI are as perfect a possible as well. Check resistance on both channels....make sure you are getting 180* of open time on each point set.
Adjust your valves as perfectly as possible
Adjust TVS as perfectly as possible.
Get rid of ALL vacuum leaks.
Make sure voltage to the system is stable at 12 volts or better
Make sure your fuel pressure is correct and stable
Adjust the ignition timing per the factory....with a strobe....and set idle speed.
In other words...make sure everything is a correct and nominal as possible.
2. Before you start this...get a spare set of trigger points. In fact get several. They are no longer made. Install them in the distributor and with a sharpy pen or a scribe....make a small mark on the centerline of the trigger points plate below the three pin plug. Make a mark on both the trigger points plate and the distributor ....so you know where the original mounting point is. Also mark the centerline of each screw hole in the trigger points plate.
Remove this points plate ........and slot the screw holes.....about 5mm on each side of the centerline mark on the screw holes. make the wholes oval....so you can slide the trigger points plate left and right....to adjust injection system timing...seperate from ignition timing. 
3. Install an accurate fuel pressure gauge onto the fuel rail.
4. with everything installed and adjusted factory normal....start the engine and leave it idling
What you are doing/observing/looking for:
When the engine is idling at factory settings in park or neutral......watch the fuel pressure gauge. It should look relatively normal and will rarely be dead stable....but will oscillate at a very high speed....across about a +/-1.0 to psi span. Meaning....if its set at 28 psi....the needle will be swinging/moving between 27.0 psi and 29 psi....this is a 1.0 psi oscillation.....which is a 2.0 psi spread. This is as off as it should get.
This oscillation at idle is primarily caused by the injectors opening and closing in pairs.....and bleeding pressure off for a split second before its replaced by pump volume. The movement of the needle....the oscillation speed....at 900 rpm will be about 7.5 oscillations per second.
Now......with the timing strobe light connected.....give the distributor a slight turn counter clockwise to increase idle timing......and watch what happens to the fuel pressure gauge reading.
At the point of movement of the distributor body.....you will see the fuel pressure gauge swing wildly....2-3 psi in both directions ....like down to about 25-26 psi and up to 30-32 psi. It will settle down in a second but will usually have a rougher and wider oscillation swing than when it was set perfectly at factory.
Try the other direction with the timing now.....it will either be slightly better or much worse. The car may try to stall in either direction.
You can see fuel pressure swings by as much as +/- 5 psi
So what's happening here?
With D-jet....moving ignition timing makes huge changes to combustion efficiency. This changes vacuum signature radically. That changes the MPS response radically. That changes the fuel mixture radically by making injector pulsewidth longer or shorter....which further changes the vacuum signature radically. This is a cascade effect.
Identically to changing ignition timing.....changing injection timing does the exact same thing. It changes combustion efficiency...which affects the MPS...which changes pulsewdith....which further affects vacuum signature....a cascade effect.
The next check......put the ignition timing back to factory normal.....and with an offset screwdriver....very slightly loosen the two screws that hold the trigger points plate tight. Just loosen them enough so that you can slide the plate with some effort.
Now.....rotate the trigger points plate first clockwise....and then counter clockwise. Watch the fuel pressure gauge each time. You will see that it increases its oscillation range wildly. It may stall the car.
Injection timing and ignition timing.....both together....and separately.....greatly affect fuel mixture, idle stability and all fueling functions.
How can you use this?
I have found that one of teh keys to FULLY tuning out D-jet ....better than factory....comes from timing the ignition properly....and then slightly adjusting the injection timing either positive or negative....until you get the absolutely smoothest most stable fuel pressure reading....at idle.
This actually means....this is the leanest point with the shortest injector pulsewidth. At that point.....you usually are slightly too lean at WOT.....but...have better control of the injection cycle and have split the difference in injection timing to the best of your ability on all four cylinders. So...at this point....you can more confidently and accurately make a slight increase to overall richness with the MPS center armature screw.
Likewise....this same method is used...whenever you install a points replacement module....because that always causes the need to have the distributor body adjusted about 5* different than factory setting....which is fine for ignition timing ....but you need to be able to bring the injection timing back to where it was at a bare minimum. Ray |
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Sat Apr 24, 2021 5:00 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Ok, all clear. Will follow it step by step, as soon as I finish the body work and painting - paint came in today (mixed to Shantung Yellow factory color) and I have some more rust repairs to do, so I want to just get all that out of the way before I focus all energy on the engine settings.
Thanks a million Ray, it's through your encyclopedic knowledge that cars like this get a second lease on life. Mine, in another year or two, might have been 'retired' forever. I saw some trigger points and distributor rebuild service offer on the classifieds, will look into that. Also, an option is the 123 electronic ignition - have installed it on 3 of our vintage cars now, and always a success.
To be continued ...
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raygreenwood
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Joined: November 24, 2008
Posts: 21507
Location: Oklahoma City
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| Posted: Sat Apr 24, 2021 6:12 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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| Cees Klumper wrote: |
Ok, all clear. Will follow it step by step, as soon as I finish the body work and painting - paint came in today (mixed to Shantung Yellow factory color) and I have some more rust repairs to do, so I want to just get all that out of the way before I focus all energy on the engine settings.
Thanks a million Ray, it's through your encyclopedic knowledge that cars like this get a second lease on life. Mine, in another year or two, might have been 'retired' forever. I saw some trigger points and distributor rebuild service offer on the classifieds, will look into that. Also, an option is the 123 electronic ignition - have installed it on 3 of our vintage cars now, and always a success.
To be continued ... |
Yes!....the 123 ignition should be really interesting...BUT....make sure you get the "fully tunable" one...that allows some timing adjustment to injection.....there are two different models from what I have been told.
I am watching those using the 123 system with interest! Once yu get that dialed in...a tweak to the MPS and some ballast for the TS-2....and you should run FAR better than factory. Ray |
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Tue May 18, 2021 7:23 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Last weekend I managed to finish work on the passenger door dent (there was a rather large dent that, while not so deep, covered about half the door's surface) and also prepped the new/old hood, that replaced the original one whose 'nose' was completely rusted through.
Then I applied urethane primer, 3 coats. Last night I managed to blocksand that all back with 320 and 400 grit. 600 grit is next, then scuff the rest of the car this week and, hopefully, this weekend a coat of epoxy sealer/primer and then the single-stage 'Shantung Yellow' paint.
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Tue May 18, 2021 7:26 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Incidentally - when I removed the lower stainless steel trim, off the rocker panels, some of the plastic clips broke. Is there a replacement somewhere available (VW or, e.g. my 1969 Mercedes uses a similar clip system for its body molding) where I can get a few of these clips?
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Fri May 28, 2021 1:50 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Last weekend I started constructing the temporary paint booth for the VW - will paint it this (long) weekend. The 411 is a relatively large car! Especially compared to the other paint candidates (240Z, Spitfire and the Lancia Fulvia). At least the booth will be plenty big enough for those, for the VW I will have to be careful.
Yesterday finished installing the exhaust filtration system:
Last week's birthday present from my son:
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Pepperbilly
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Joined: April 08, 2017
Posts: 977
Location: Seattle, Wa
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| Posted: Sat May 29, 2021 3:14 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Hey Cees,
Wow, your project is coming right along! Very ambitious in such a short time. Can’t wait to see the finished product. I am also looking for those rocker clips. They are a 411/412 part only. BugCity back east shows some in stock but super expensive! If you want to look there you have to type in the vw part #. Let me know if you find anything else.
Bill |
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Sat May 29, 2021 8:18 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Thanks Bill! Will check out those clips at BugCity. And the Mercedes suppliers, they may fit with a bit of adjustment.
Today I spent most of the day constructing (literally) the intake / positive pressure filter-and-fan-box. Lots of lumber and screws. Now I have 40 square feet of intake filtration, a fan that really moves air, and also 40 square feet of outgoing / overspray / fumes filtration. Also constructed the door to get in and out of the booth. Tomorrow will cover all the walls, the floor and ceiling with 4 mil plastic sheeting. Also will so some final-final sanding of the 411, washing, cleaning and moving it into the booth for final pre-paint degreasing, masking and so on. Then Monday if all goes well, one coat of epoxy primer, then two coats of the single-stage urethane Shantung Yellow. Wish me luck ...
the intake filtration almost finished:
how it is all looking as I am typing this:
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raygreenwood
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Joined: November 24, 2008
Posts: 21507
Location: Oklahoma City
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| Posted: Sat May 29, 2021 9:49 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Niiiiiiiiiicccccccce!
I have worked in clean rooms that are worse than that!
Ray |
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NurseryWalt
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Joined: January 29, 2016
Posts: 143
Location: Abbotsford, BC
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| Posted: Mon May 31, 2021 10:18 am Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Cees,
That looks awesome! Keep up the great work and take lots of photos.
Walter
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Mon May 31, 2021 10:37 am Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Thank you gentlemen! Finished the booth yesterday, the positive pressure and filtration system appear to work very well. Car is now washed, sanded and masked up inside. Getting painted today, will take pictures indeed. Hope tonight will be a good result.
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Mon May 31, 2021 7:12 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Just finished the painting. Phew! It came out well, although I was battling two issues: firstly, the spray pattern of the gun was not even - rather than an elongated 'football shape' it was more like an hourglass shape, with more paint toward the top than the bottom that also came out kind of 'thick' despite the paint being pretty thin (I added 10% reducer). Playing with the settings (air pressure, amount of paint, amount of air, fan shape) also did not really help. I managed to made it work, but it was not as expected and more difficult to get an even coat. This is a $30 gun which had good reviews but perhaps I just need a lot more practice.
Secondly, some of the inevitable overspray settled on the floor, which I had covered with the same 4 mil plastic sheeting as the walls and ceiling. In the beginning, when I put on one coat of epoxy primer, that was all ok, but as I was applying the finish paint, especially the second coat, my sandals started picking up the semi-wet paint on the floor plastic, and it was sticking to the plastic. Sort of like walking on fly paper. The soles of my slippers became sticky and covered with tacky paint, which I then tracked to the working area outside the booth where I was mixing up the paint, filling the gun etc. After the second finish coat, I had enough paint made for a third coat, but by that time the floor plastic was so sticky, I was afraid to try and apply the third coat. Anyway, even after the first coat the paint looked quite good, and the paint instructions called for 2 or 3 coats, so I decided to call it a day. Here's some pictures. First of the epoxy primer, then after the second color coat.
There's just a bit of dust specs that somehow made it onto the hood, not the rest of the car (I must not have cleaned out the intake filtration box properly) so I will wet sand and buff that out. Almost no orange peel, so far it looks very good. Will need to see it outside, and will most likely need some color sanding/buffing, but that's ok:
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hulken
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Joined: January 29, 2009
Posts: 95
Location: Norway
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| Posted: Tue Jun 01, 2021 4:28 am Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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That turned out really nice, despite your problems with the gun. Congratulations on a superb result!
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Wed Jun 02, 2021 4:32 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Many thanks Hulken! Some small issues to address but I am very happy with the result. Car looks somehow 'chiquer' now, the paint is very glossy and 'thick' compared to the lighter/yellower coat before.
Upon reflection (pun intended) I think I did not clean the gun adequately when I moved from the epoxy primer to the finish paint, and that caused my poor spray pattern.
Some more photos, now outside. Can't wait to put the bumpers, lights and other trim back on for the Full Effect:
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Sun Jun 06, 2021 5:45 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Have been putting all the exterior trim and lights back in/on, all done now. Car looks really good. Then today I decided to put the old shocks back in, since the new old stock ones I had bought were basically shot out of the box. Way too weak, very little resistance. Plus, recently I found a post from a previous owner of this car, saying he had among other things replaced the shocks. The old ones were Sachs, the NOS ones I am ditching are Boge. Now the car rides better again.
Another thing I did was to install the new engine-to-body seal. The old one was barely there, gone in about 1/3 of the length. It was a bit fiddly but not too hard.
Question: inside the car it seems much quieter now. Is that possible because of the new seal, or just imagination?
Question 2: the engine compartment just below the floor, and also the exterior spot right underneath the rearmost window and the tops of those louvered vents, and even the lock thing you press to open the rear hatch, all were quite warm to the touch after my long drive, something I never noticed before. I took the engine cover off and it was quite warm as well, seemed much warmer than before I replaced the seal. Is that all normal / the way it's supposed to be? As far as know, that seal is very important to keep the engine cool. I guess if that is correct, it will also prevent the heat from the top of the engine to 'leak out' to below the car, if that makes sense.
Anyway, it runs like a top, starts up quickly, idles great and there's none of the hesitation off the line that it had when I first got it, so I think I am leaving well enough alone for now. When cruising at say 45 MPH in third, when I press the throttle into the kickdown, it really revs easy and pulls hard. But normal coasting along, it's quite comfortable.
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Cees Klumper
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Joined: March 13, 2021
Posts: 60
Location: Long Beach, California
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| Posted: Sun Jun 06, 2021 5:50 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Photos of how it's looking now. I picked up self-etching primer and chrome spray today, to try and rejuvenate my front bumper a bit. The chrome is really past it, and so is the rubber strip, but I found someone on CL who says he has some NOS ones for the 411/412, so hopefully this will round things off. Only things left are some details in the interior.
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Pepperbilly
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Location: Seattle, Wa
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| Posted: Sun Jun 06, 2021 6:47 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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For as quickly as you did this the old 411 looks really nice! Be very careful about anyone offering bumper impact rubber. The front bumper is 411/412 only because of the length. The rear is the same as a late model Type 3 or maybe Ghia. Nothing in common with a Type 1. I have been looking for months for both front and rear as close to new as possible or NOS. Can you let me know if you find something?
Bill |
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Cees Klumper
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Posts: 60
Location: Long Beach, California
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| Posted: Sun Jun 06, 2021 7:02 pm Post subject: Re: Newbie with a '71 411 3-door sedan automatic |
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Hey Bill, actually the strips he has are not nearly long/wide enough, 68/69 inches, while mine is more like 90 inches. Will need to look for an alternative.
Like yesterday, to put that lower molding on on the rocker panels, I found GM clips at Autozone that ended up working fine, alongside the original ones I had left. They are sold in sets of two in those small blister packages. Brand 'Needa?' and the code is 480130 GM Body Side Molding Retainers:
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