View The Full Version : Advance injection 1.3 Mjt - MJD8 vs MJD6
It's a bit that I was studying the maps of the advance of the 1.3 multijet and compared to that of a MJD8 that comes from a project that OLS should come from a damos... and then conftrontavo with that of my Point 70CV then MJD6.
For? in tabular cos? as from the file OLS for me not to ? correct ilverso of reading, in fact, the degrees of advance will increase with the increase of the rpm and not the contrary.
6670
But, as I said, for me, has to be read in this way:
6671
In MJD8 the map ? 8-bit with a conversion factor of 0.3 (at least from what c'? in the file OLS...) while in the MJD6 the map ? to 16 bits conversion factor 0,015625 (from what I've found on the net)
The 70 HP then works with advances more perhaps due to the lower pressure of the rail, and then the resulting time of injection pi? high.
Now wanting to optimize the advance on my engine, 70 HP that calculations must be made to compensate for the increase of the injection timing? So do not go in afterburner but even in precom.?
These that I have analyzed should be maps of the main inj.... as we all know, the multijet has several injections... pre and post...
To do a good job, you should also change the maps of the pilot injection and pre-injection?
The post injections that would serve to increase the temperature of the catalyst or DPF if this can be deleted (since I know of no use at all for the performance)?
I know it's not ? an easy subject but I hope someone can help me and help anyone who has these questions.
Thanks
hgtferma
07-03-2014, 12:45
It's a bit that I was studying the maps of the advance of the 1.3 multijet and compared to that of a MJD8 that comes from a project that OLS should come from a damos... and then conftrontavo with that of my Point 70CV then MJD6.
For? in tabular cos? as from the file OLS for me not to ? correct ilverso of reading, in fact, the degrees of advance will increase with the increase of the rpm and not the contrary.
6670
But, as I said, for me, has to be read in this way:
6671
In MJD8 the map ? 8-bit with a conversion factor of 0.3 (at least from what c'? in the file OLS...) while in the MJD6 the map ? to 16 bits conversion factor 0,015625 (from what I've found on the net)
The 70 HP then works with advances more perhaps due to the lower pressure of the rail, and then the resulting time of injection pi? high.
Now wanting to optimize the advance on my engine, 70 HP that calculations must be made to compensate for the increase of the injection timing? So do not go in afterburner but even in precom.?
These that I have analyzed should be maps of the main inj.... as we all know, the multijet has several injections... pre and post...
To do a good job, you should also change the maps of the pilot injection and pre-injection?
The post injections that would serve to increase the temperature of the catalyst or DPF if this can be deleted (since I know of no use at all for the performance)?
I know it's not ? an easy subject but I hope someone can help me and help anyone who has these questions.
Thanks
hi faith, can I ask you why? you need this info??if you make a map with push ok but otherwise the 1.3 for a map to soft and slowly increasing too much the time of injection should be already more than good...
it is, however, the advance has to be seen to the contrary
Hello, the idea was to maximise my Point 1.3 70CV... now I am undecided to mount the BV35 gi? modified with geometry that works with a wastegate... or put on the GTB1549V derivation of the 2.0 Multijet 170 CV, even if, perhaps, the solution pi? sensible would be the middle of the road... or the GTB1446V of the 1.6 Multijet
Now, following some advice I am limited to anticipate of 1.5 degrees with respect to the original.
if I remember well, and was told somewhere else that does not anticipate a diesel cazzum....
worth serious problems...
to act with knowledge of the facts you need to calculate how many degrees does the main injection from microseconds to degrees of motor rotation, and by them out where we can? push with the advance...
we put the case that your injection to 4000 rpm is 890us that have been converted with a formula that now I don't have on hand correspond to a duration of 25? of the rotation, if at 4000 rpm with the iq that you are injecting the ecu adopts an advance of 20? (random numbers) you know that your injection ends 5? after the pms....
time and belief in general that you should not inject more than 10? after the pms....
I sincerely for the few maps that I adopted another strategy....
It is, in fact, I just wondering for advice on how to anticipate correctly. Unfortunately ? a topic that perhaps few know in detail.
Cos? as I have done, I know that's not good.
I think I told you how to do it anyway....
search for the formula and made the calculations..
already by doing so you will realize for yourself that the main injections are not exceeding never tot of degrees duration...
Ok, prover? to understand how to do the calculations.
Thanks!
Then from what I understand I don't have to have injections over 10? after the pms but as the beginning of the injection?
Somewhere I read as the beginning of the injection values of 20? before tdc...
In the original map of my Point 70 HP I have a maximum advance of 29 degrees (IQ greater than 26 mg/stk and 4688 rpm)... Possible?
If it were so? I could inject diesel to 39 degrees (29 btdc + 10 after tdc) without and then go in afterburner?
angelus.d87
02-04-2014, 17:06
but the advances that address have?
Then from what I understand I don't have to have injections over 10? after the pms but as the beginning of the injection?
Somewhere I read as the beginning of the injection values of 20? before tdc...
In the original map of my Point 70 HP I have a maximum advance of 29 degrees (IQ greater than 26 mg/stk and 4688 rpm)... Possible?
If it were so? I could inject diesel to 39 degrees (29 btdc + 10 after tdc) without and then go in afterburner?
not ? just so....
in your case you know that your iq(26mg) at 4688 rpm you an advance of 29?.....or? you know when to start the main injection....but as I hinted before, you know how many degrees it ends??
10? they are a non-written rule that for? pu? vary from engine ? engine especially as we use the v? to set the "hardware"...
if you know how many degrees of duration angle match your injection times with the advances in hand, you can already? get an idea of how the manufacturer decided to go with the duration of injection in addition to pms.....
remember that when you are searching for high power with degrees quantity? diesel fuel is of primary importance to monitor the egt....
there is a mathematical calculation to do and not many people know about...in the maps of advances intervenes with the policy otherwise you do damage, and then in the single map change to all points on the basis of the duration of iq...
if I remember well, and was told somewhere else that does not anticipate a diesel cazzum....
worth serious problems...
to act with knowledge of the facts you need to calculate how many degrees does the main injection from microseconds to degrees of motor rotation, and by them out where we can? push with the advance...
we put the case that your injection to 4000 rpm is 890us that have been converted with a formula that now I don't have on hand correspond to a duration of 25? of the rotation, if at 4000 rpm with the iq that you are injecting the ecu adopts an advance of 20? (random numbers) you know that your injection ends 5? after the pms....
time and belief in general that you should not inject more than 10? after the pms....
I sincerely for the few maps that I adopted another strategy....
Then I want to explain a p? things to improve? many people start to learn...
suppose that at 5000 and 60 mg we have a map duration of 44? and a SOI of 27? before TDC...
we know that the duration for these 60 mg ? 44?...but how do we calculate the duration if we want to increase the mg diesel?
so if you take some? inject no more? 60 mg but 65 mg make? 65 x 0,733 = 47 ?
now with 65 mg we will have a duration of 47? and a soi 30? before TDC...
Yes, but there should be a formla that you rule to the other regimini and not only at 5000 rpm
As a rule, the SOI most of 3-10? non pu? go why? pu? cause serious damage to the engine...there are so many calculations behind it and can't explain them here in two words...normally if you increase the mg should be increased as the duration and SOI...I'll give you a small example in words, so at least you can understand: get in the car turn the car starts to give gas, behold, in this moment, the ECU goes to act on the map the pedal and understands that for that 30% acceleration needs to inject 16 mg so far so simple...but the ECU for these 16 mg should decide on a SOI and a duration.
The designers of engines measure the time in degrees of rotation, that is why? you hear people talk about engine timing. The ideal point to inject the fuel ? the top dead center TDC. This ? the point where both valves are normally closed and the air ? was crushed to the maximum.
Inject 16 mg of fuel to the avr? a time (duration), why? the piston is going up and down??we need a point of BEGINNING OF INJECTION.
Suppose that 2 mg of fuel take 1 degree of rotation of the motor shaft to inject.
Assuming that the best time of injection ? 0 ? before TDC and 16mg avr? 8? to inject(DURATION).
Exelion1986
16-10-2014, 13:23
if it can? to be useful, here are the accounts:
revolutions per minute / 60 = revolutions per second
revolutions per second / 1 000 000 = revolutions per microsecond
revolutions per microsecond * 360 degrees = degrees per microsecond
degrees per microsecond * injection duration (in microseconds) = time of injection in degrees
then I would like to raise another question
take, for example, the last column (the one that spins the most? high) and we see that it ranges from 26 to 29 degrees of advance
but of course, to inject a few mm3 of fuel it takes only a few degrees, which is absolutely not 26
in other words, we see that equality? iq, and rpm increases, it also increases the advance
then as you rule? I are two alternatives in mind: a ? put the calculated values and, in fact, distort completely the advance control to the partial, the other ? calculate only the maximum iq and then give a scalatina hand in hand down the iq...
voglioimparare
18-11-2014, 09:04
As a rule, the SOI most of 3-10? non pu? go why? pu? cause serious damage to the engine...there are so many calculations behind it and can't explain them here in two words...normally if you increase the mg should be increased as the duration and SOI...I'll give you a small example in words, so at least you can understand: get in the car turn the car starts to give gas, behold, in this moment, the ECU goes to act on the map the pedal and understands that for that 30% acceleration needs to inject 16 mg so far so simple...but the ECU for these 16 mg should decide on a SOI and a duration.
The designers of engines measure the time in degrees of rotation, that is why? you hear people talk about engine timing. The ideal point to inject the fuel ? the top dead center TDC. This ? the point where both valves are normally closed and the air ? was crushed to the maximum.
Inject 16 mg of fuel to the avr? a time (duration), why? the piston is going up and down?...we need a point of BEGINNING OF INJECTION.
Suppose that 2 mg of fuel take 1 degree of rotation of the motor shaft to inject.
Assuming that the best time of injection ? 0 ? before TDC and 16mg avr? 8? to inject(DURATION).
i'll give you my congratulations! you're one of the few who has the desire to explain things that others would take for them undoubtedly! I am also following I the discussion why ? very constructive!!!
voglioimparare
18-11-2014, 13:50
we post a sample file and we do this step together? it can be constructive, x it is an example of this kind...:)
jacktheripper2
20-01-2015, 01:14
now with 65 mg we will have a duration of 47? and a soi 30? before TDC...
The SOI for? becomes 30 degrees if you want to have the same EOI, otherwise you can? keep a Soi 27 and finish it to? injection 3 degrees later than the original.. Especially if you are talking about quantity? high keep the same EOI is impossible unless you anticipate a lot
then we see a little bit if you find yourself with me:
I climbed on the break of the rail in advance and the driver wish to inject 65mm3 up to 5500 rpm, the injection time is not c'? need to redo them why? in the map we have already? the
65mm3 serving.
these are the results of my calculations on the basis of the new injection time:
At this point, I'm a little bit lost in the sense that if the injection now lasts 48? at 5500 rpm it means that the 29? original I need to add more
19? of advance?
then we see a little bit if you find yourself with me:
I climbed on the break of the rail in advance and the driver wish to inject 65mm3 up to 5500 rpm, the injection time is not c'? need to redo them why? in the map we have already? the
65mm3 serving.
these are the results of my calculations on the basis of the new injection time:
At this point, I'm a little bit lost in the sense that if the injection now lasts 48? at 5500 rpm it means that the 29? original I need to add more
19? of advance?
You are completely out of the way.
A 16v injects already ori 65mm3 about and does not even need to touch the advance. And the duration for 65mm3 at 5500 rpm ? 27 degrees..
Then you need to do 5500 rpm with turbo ori?
I would not want to go off topic, not horsemanship turbo ori, I the duration of the intake and exhaust elongated and also the 1.3 mjet from the original injects stops at 45 mm3.
the duration ? 27 degrees perhaps with time the original
and also the valve lift is not ? the most original (close ot)
According to me in the 70cv, to reach those injections, you need to begin to replace the high pressure pump and the injectors with the ones from the 90hp....
help me understand how do you calculate the duration in degrees?
I multiplied the duration in the Us for 0.000006 that should be a fixed number for the number of revolutions of the engine
According to me in the 70cv, to reach those injections, you need to begin to replace the high pressure pump and the injectors with the ones from the 90hp....
The CP1H of 90hp avr? also pi? pressure but less flow..
I investirei in the change the CP1 of the 70cv with pistons and rotor...
injectors 90hp damage 9 Milligrams to 1450Bar with 400 blows
I would try the injectors that fit in the mount with the same angle of spray that will give at least double..
yes, but the point is it not ? this, according to you ? correct my reasoning or how I have to move on?
should be scaled also, the axis of the maps out of the driver?
I agree for the pump, even if, according to the objective you want to achieve, you will directly to that of the 90hp....
Regarding the injectors, I recalled, had the same vaporizers... (we have a lot of ot)
With regard to the conversion from us to degrees of rotation, I refer back always to this:
degrees= [rpm/60(r/s) * 360(degrees/s) * Tinj(time in us)] /1000000
Then:
degrees= Duration in us / 1000000
then, 1183 (time in Us) / 1000000=0.001183 how many degrees would be?
instead, if we duration * 0.000006 * rpm we
1183*0.000006*5500=39? it seems to me more correct as the calculation
(these are the duration of the original map)
And' what I have written I...
In summary:
Degrees = [rpm (revolutions/min) / 60 (to get rpm/sec) * 360 (get degrees/sec) * Tinj (us)] /1000000....
from which [360/60]/1000000=0.000006
then... rpm * Tinj * 0.000006 = degrees
I hope I was more clear.
we said the same things in different ways.
then, according to you ? just the calculation that I have done? the table that I posted ? exact?
maybe... it would be very interesting
according to you then ? correctly calculate the length in degrees of the original map and add the map to advance the difference between the times gold and those mod?
I also like the strategy I avoid tap advances changes are not extreme... If I make a change the more heavy with mechanical ori arrival for a maximum of 2 degrees of advance and always with an eye to diagnosis and personal feelings!
In the case of the mechanical changes of the type of fairy turbine, then the discussion changes, and come into the game too many factors to say that there is a strategy unique...
According to me the difference between the times ori and mod can be considered as indicative but not mathematically exact... that is' not' said that if there are 20 degrees of difference in the duration must anticipate additional 20 degrees...!!!!
instead, I think the opposite:
the original map, however, still has a mathematical logic to ensure that the injection takes place at the exact moment, and if the injection lasts tot degrees in va early
same number of degrees to make it finish at the same point as the original, this is theory but ? obvious that may not be so.
anyway ? very nice to exchange opinions with you
Thanks... I try to study and learn as much as possible, and surely the exchange of ideas, opinions and experiences is a fundamental...!!!!
I agree, just a shame that we are not arrived yet concrete results
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