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Injector deadtime

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I'm kinda hoping for some help I'm searching all over for info on these injectors dead time @13.2 volts as well as the battery voltage correction needed. Thought maybe soneone might have the info handy, I know since they are high z I'll set current limiting off. Wanting to make sure since I'm gonna dyno very soon and I want to do things right!!

441cc 42lbs Bosch 0280150558

I'm using these drivers too

Thank you!

Attached Files

Based on looking at this injector in another ECU, I think the following deadtime info might useful:

3-bar differential pressure

8V - 2.479 ms

10v - 1.722 ms

12v - 1.335 ms

14v - 1.106 ms

15v - 1.019 ms

Interpolating for your requested 13.2v, I get 1.1976 ms

Hey thank you! One of the concerns that i have had is that some of the info ive gotten from other Bosch injectors has been lower like into the .7 ms as well as a listing for what i think the injector were used for originally in the ford lighting. would it be safe to say larger injectors have larger deadtimes? Also is there a way to find the voltage correction? as well as a way to know if the deadtime is correct once applied?

Thank you again for you help i'll try those figures but i'm guessing the only real way to know for sure is to bench flow them.

Megasquirt ? (based on your picture)

If the offset ("deadtime") is correct, the change on the AFR table (or VE table) would be point on with the the AFR value.

IE: 10% increase on the table would be 10% more fuel.

As for the specs of your injectors:

Bosch 0 280 150 558 = Ford M-9593-F302

So, @13.2V

0.755ms for 39psi (2.7bar)

0.780ms for 45psi (3.1bar)

And the correction would be ~0.120ms/V

yes megasquirit didnt want to out right say it because of some negative things people always say! thanks i'm positive those are them. they came in a kinitic vr6 gti golf turbo kit i bought but long story short i am not using them on the chip tune anymore. thank you for your help! i hope most people wont hate on that brand i feel it has come a long way since it started and i have had nothing bad to say about the people that use it and build and support it. thanks again for you help both of you!

The car seems happy with those settings, afr's seemed more stable as i was running auto tune tonight i didnt get a chance to -+10% yet since my map is fairly rough, looking forward to switching to Lamda and doing some steady state with in the next few weeks... on a side note i gotta fix my stupid IAC it seems to get stuck or maybe its all cause by the way i have it plumbed with just a filter and not plumbed but into my intake piping i dont know but its intermittent so it's leading me to thinks its just the valve. havent been too worried about the miner boost leak

Sorry if my values weren't correct. Another way to verify deadtime settings, is to switch between batch fire injection (ie, squirt once per rev), and sequential injection (once per cycle ). The Lambda or AFR reading will not change if you have the deadtime set correctly. If it's leaner in batch mode, then increase the deadtime to cause actual pulse width to increase.

If your ECU can do that on the fly, it's an easy test.

Batch fire or sequential has nothing to do with the number of time each injectors opens but if they are commanded all together or alone.

For example you could open all injectors together once per cycle, that doesn't mean it's sequential.

Other than that, changing the number of squirt (when you can) is a good idea.

With a megasquirt you can't change on the fly the number of squirt per cycle (or the type of injection) but it doesn't have to be as long as you can go on the same cell. (like idle)

Same rule for apply for tweaking the VE value to see if the offset is OK.

Anon, I guess you have a DIYPNP with the "injection kit" module ? (paired two by two as follow: 1-6; 2-5; 3-4)

If so, I guess you have it set to "alternating" and 6 squirts per cycle (2 for each pair), so semi sequential injection.

actually i just have the standard ms2 batch fire i can not run sequential.. i used that photo because i heard that injector driver can change the injector characteristics and wanted to give all the possible info. David no worries i had actually been running it very close to those figures you gave for a long time and the car ran well but im glad we got it sorted thank you. here is a picture of the beast and the idle valve on the left of the log short running open to atmosphere

Thanks again ill confirm the changes tonight by adding and remove some fuel.

Attached Files

Okay so tonight i got to play with the car got the idle valve sorted! i added 20% more fuel at 14.0ish afr at idle it dropped it down to 12.0 12.2 from my calculations tho that not 20% 11.2 would be or am i wrong? if its wrong is there a way to get an idea of what the deadtime would be from it? also i know how to add fuel by percentage on megasquirit by putting 1.2 into the math bar but i dont know what math to do to remove it, does anyone know?


LUDO when you get a chance could you teach me how you used that data sheet to get those figures?

To reverse a multiply of 1.2, you either divide by 1.2, or multiply by the inverse (ie. 1 / 1.2 = .83333).

I would expect the AFR to drop to 11.1 - 11.2 if you were at 14.0 with a 20% increase in fuel. (and to 12.5 - 12.6 if you were to use a 10% change). I suggest you change your deadtime in small increments and change the table back and forth until you see the commanded change give the expected result.

so i think i figure how to add subtract by % so thank you. so my math was right and m dead time are off i'm gonna set my base fuel pressure again engine off pump on to 3 bar to confirm that but im pretty sure its correct since i just finished a surge tank and pump install. If you were to guess would it need a increase in deadband time? also given those figures why would it be off i'm 90% sure those are them unless they are china knock offs which i doubt that kintic Motorsport would sell. Are we reading it right seems like theirs a lot there to take in

Thanks again Im learning tons

There is two "point" to consider for the injector data.

One is the offset, the other is the maximum theoretical flow.

If one or the other is wrong, the slope is wrong and so will be the result.

In the Ford datasheet, the flow is 43lb/hr (451.6cc/min) @ 39.15 psid

That's a 2.5% difference to the value you provided.

if you start with an AFR of 14:1, a 20% increase of fuel should give you exactly 11.67:1 (14/1.2 !), not 11.2.

If you have 12:1 instead, that's 16.7%, so a 3.3% error.

You should make a log next time, it's a lot much more easier when you can see the pulsewidth and corrections (that can have a huge impact)

it's looking like my high school math teacher was right i should have paid i bit more attention to her>>> LUDO If i can upload a log from Megalogviewer can you view it? I'm not sure to what exactly i'm gonna be looking for and would love to learn how to use that info better thanks again for even taking the time in the first place! i can also setup and flow test them if that would be the better and fast way overall i'd just need to buy a few things

I'm a megasquirt user too, so yes I can view it. (i have both Tunerstudio and Megalogviewer)


here is what I would use (for 3 bar)

Required fuel -> Injector flow: 45.4 lb/hr (or 477cc/min)

Injector dead-time @13.2V: 0.775 ms

Battery correction: 0.120 ms/V

Attached Files

LUDO Thanks i will try the editedt setup later tonight, let me send you my msq and a datalog so that you have some info on your side the car runs pretty good but id just like to have it setup correctly before i spend time on a dyno ... one question i did ask about is lag factoring does that just smooth the spikes in my datalogs?


edit it wont let me post my msq or datalog do you have a email? and what should i use for engine displacement? stock? i'm bored to 82.5mm 8:5 to 1

hey good new the car is much more stable at idle with those numbers!!! are we not quite there yet if i add 20% and it only drops to 12 or is that a normal situation/acceptable? the only thing that could be off on my end from those figures that you gave is the displacement like i brought up before..

thanks again for everthing

Of course the displacement as a huge impact too.

With 82.5mm, you increase the displacement by 104cc.

Stock 2783cc, now 2887cc <- that the number you should use.

Also, you should check the voltage at the injector (with a multimeter) and make sure you take into account any discrepancy with the value on tunerstudio.

Finally, of course you can post your MSQ / MSL here. You just have to do it before the "time out" (happens if you're too long to time your message)

Best way to do it is post your message, hit the "Edit" and add your file(s) ;)

Thanks man you're like a fountain of knowledge!! I'll check my voltage and factor in my new displacement .. I'll try get a log upload like how you said to too

Thanks again!

Attached Files

Okay car off battery volts it cold out was 11.8 running was 14 at the battery stable... At the the injector it was 13.84 +- .2.. till the fan turned on and it drop to 13.5+-2....I did my best to correct MS focusing more at the running volts and got it within .5 of the two injectors volt reading.

i'm also gonna check for any timing drift i dont think i have any but i want to make sure..If you don't mind looking at those attachments maybe you might see something i missed or could do better on

Thank you!