Trials and testing Will van Gemert
Turbo Mini Forums

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I'll try to give all answers in once:
(I was not able to bye new plugs today tomorrow I will test with new plugs.)

I am using a ford edis coil pack with the leads that go with this coil pack. I thought I did not need resistor plugs but I might be wrong? Lead resistance is 5K, spark plug resistance also about 5K

About the second trigger I checked this with the diagnostic function of tunerstudio and everything looks fine there. Above that it never runs good always lean on two and rich on the others (did however run good before) and it swaps consequently when swapping the plugs.

My dwell settings are: maximum dwell time 6msec acceleration comp. 1 msec max. spark duration 1.5 msec. Thought this was more or less standard

Graham, about your remark on the afr’s not seeming to change when changing the injection timing and this perhaps being the same problem. I think this was caused by not switching on and of the ms after going to hybrid mode Paul might have been right on this but I could not test this anymore because off the current problem. (will be continued)

Checked the Ford fiesta manual the edis coil pack and leads I am using needs resistor plugs so bought a set of NGK BPR7es put them in and all is ok again! I went back to square one and I am now first trying to get it as right as possible with the 460 cc injectors I know these are too small but then I just won’t go full throttle with them. I took the car around the block with ve-analyze live running. The car ran reasonably ok but still a lot of work to do I am now trying to analyse the data to see what I can optimize after that I will take it around again and will post the datalog to share it. For now I am a happy man again.:)

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Schrödinger's cat - so which one am I ???

After having analysed the data of my first run I made a few changes and took the car for a second run ( it looks a little bit better than the first). I have attached my MSQ file and the datalog of this run. It is setup for speed density and single table injection timing, hybrid mode is disabled. Although the log shows a lot of room for improvement the engine runs ok it’s quit responsive on the throttle especially when low on the throttle. It is hard to get it to idle correctly I will first try to get the optimum with speed density before I switch to alpha-N which might be the better choice for my cam. I will try to analyse this run and see if I can get it better ( I am new to this compared to almost all of you so I can use all the help I can get).

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Your log looks pretty good as it is. It's probably not worth getting too hung up on getting the AFRs exactly equal, but if you want to improve it then have a look at this:

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=319675

I could email you the spreadsheet with minimal data if you want to go down this route.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

will ,if it helps ..

with that cam ,id be expecting a 1200 rpm to maybe 1400 ,for a smooth idle .for a rumpy rumpy idle i'd expect around 900 to 1000 rpm .

this would depend on valve port size and rocker ratio ,and any anti reversion you may have designed in .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Paul,

Thanks for the complement but I must say the logs I saw from you are looking much more stable and equal in AFR's I am far away from that!. I am quit good with spreadsheets and understand what you did very smart to use turntables fore this. Can you please send me the worksheet? Would love to see what it will give with my log.
regards Will.

Robert,

I’ve got 36mm inlet and 31mm exhaust valves both rimflow. Rocker ratio is 1.5. No further provisions to prevent reverse flow. The engine idles smooth at 1500 and above but drops of quickly below that and will stall.
regards Will.

Just noticed that I had my VE bin wrong this had the values for alpha-n instead of the values for speed density I think this is one of the reasons idle was not so good and also fuel load throughout the range was far from optimal as effectively I was using only half of the table!

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Paul,
Your Excel spreadsheet is very useful It shows exactly where the problem area’s are from a injection timing point of view. It shows in my last log that timing is off between 3000 and 4000 rpm and a map between 85 and 55. also very interesting to see is the area at a map signal of 60 to 65 there it goes from rich on the inners to rich on the outers over arev range from 3000 to 5000 rpm. The run was made with the attached timing tables. Pdf of results also attached red is running rich on the inners and blue is rich on the outers. To be continued

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Glad you found the spreadsheet of use.

We found it the easiest way to see where adjustments were required, rather than trawling through the datalog charts.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Edited by robert on 25th Apr, 2011.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

What is your injection strategy then Will?

Two injector timing tables and a single VE table?

Graham T has used this method with success, detailed in this thread:

http://www.turbominis.co.uk/forums/index.p...tid=350549&fr=0

Personally I prefer the hybrid mode. We did some tuning of the MS3 yesterday. Just set the VE Analyse Live running and concentrate on a single timing table.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Paul,

At this moment my injection strategy is single timing table and single ve table. I thought it was sensible to keep things "simple" to start and try to optimize with that as far as possible before going to dual timing and or ve trim tables. After having optimised this (as far as possible) I have planned to test hybrid mode to see if that gives better results.
I am slowly getting better results with the current settings at this moment the engine idles ok at 1500rpm but I'am experiencing the following. When I have idle to drop to about 800 rpm I get equal AFR's with a lumpy idle then when increasing to around 1500 the outers are going lean ( I can not fix this with single timing no matter what I try) then when going to fast idle (2000 rpm) I am getting equal AFR's again.
Next thing I am going to try is using the VE trim tables to see if that brings any improvement. On the other hand I think it might also just be the effect of reverse flow of the inners wich causes the outers to suffer 1500rpm is the point where the engine starts to get 'on cam' then at very low RPM (800 and lower) it is that much ‘of cam’ that both inners and outers are perhaps suffering equally. I will read thru the tread you mentioned.
To be continued.

Wil

I took a good look at the strategy that GrahamT used (timing the injection pulse of the inners in such a way that some of the pulse enters the outers to get equal afr’s).
I started with getting things right at idle and then moved to the full throttle area and it did not take long to get reasonable results see graph where I go thru the gears at full throttle. (you can see where the pulses merge and the all goes lean around 6000rpm.) After this I started to work on the tables in the part throttle region with my girlfriend driving the car. My experience is that the quickest way is to use Pauls tool to find the problem area’s and then make adjustments while driving the car in that area. I have the timing tables attached which gave the best results up to now. When examining the numbers and doing some math at 4000rpm I realised that the timing values I used with the single table were far from correct. 4000rpm and injection time of +25 and a pulse width of 3,7msec saw already some of the pulse of the inners going into the outers this means I will have to inject much earlier.
I had my ms to loose its complete program! I had to reload from scratch with the bootload jumper. This occurred while driving with VE-analyse live running. I think it happened when I tried to burn new values at the same time that ve analyse burnt new values. Has any of you ever had similar problems?

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I've not had the problem that you have experienced. Maybe it is not a good idea to burn new values whilst VEAL is running.

Other than that, Congratulations. You seem to have cracked it.

How is idle now?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Paul,

Idle is much better now in the sense that it idles smoother but it still drops quicker and further down when going ‘off cam’ compared to the carburetor. Using GrahamT’s approach is, as I see it now, in fact a bit like doing semi hybrid because you time table two in such a way that the pulse goes to both the inners and the outers. Having said that I think that going to hybrid mode might be the best (easiest) option with the big overlap of my cam to maximize the amount off fuel that can go in with a minimal size injector.
Theoretically I should be able to get more fuel into the engine then with a normal cam because my injection window for a cylinder pair is 286+286-122(total overlap)=450 degrees this gives a maximum window of 225 degrees per cylinder in theory. In real life that still should be something like 200 degrees taking into account that it there will not be happening much in the first and last 10 degrees of intake valve opening. This sums up to a duty cycle of 36%. It will not be before Saturday that I can start testing this because I also have a steering rack problem. I had had bought a new (rebuild) steering rack and had mounted it without pre-inspection to find out now that its rubbish It’s a rack with a plastic nut off about 33mm to set the pre-load of the rack and pinion. The plastic nut has been pushed out (or over tightened during re-build) and is useless now. Never seen a rack like this is this from a later mine?? As I am only used to work on older mini’s (pre-1978) I had never seen a rack with this kind of nut. (seems rubbish to me but then again I have no experience on these)
Wil

You seem to have reached the pulse width limit at 7k.

6mSec at 7k is over 250 degrees.

What injectors are you currently running?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

No help on the fuelling side, but could your falling revs at low rpm be an air speed thing?

I only ask as my 205 would do this- on returning to idle say if clutch dipped from 3000rpm with throttle closed, the revs would drop too quickly and it could not "catch" itself so would cut out.

It was setup with a small clearance on the throttle butterfly, and a small air bleed bypass.

The way I got around it was to open the butterfly clearance a touch which increased the idle, and then wind down the air bleed to get the idle speed back down. My theory that the sudden drop in air speed on overrun and increase in vacuum wasn't enough to pull air through the bleed to catch the engines falling revs.

With the adjustment done it sorted it.

Possibly not your problem but worth a think about.