• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Injector dead time

That's fine. Still isn't the place to be hate****ing each other. Not you Gary. Mostly ZVOLV, Nick, and Kenny. I love you guys but come on.
 
Strides in, waves big flaming stick around, shouts in loud voice, implies nobody else gets any.

That's how I spread love and good cheer as well.

EDIT: I'm just razzin ya man. This thread could be a lot more mmmmmm zippy. It just it needs zazz.
 
Last edited:
That's fine. Still isn't the place to be hate****ing each other. Not you Gary. Mostly ZVOLV, Nick, and Kenny. I love you guys but come on.

The **** do you want, guy? Seriously. We don't own your car, you do. The entire reason Bosch, Rochester, Deka, et al don't publish how long it takes for the injector to deliver fuel from the time it's energized is because that information has nothing to do with their hardware. Many factors play into this, the entire idea already discussed by Kenny in this thread. The methods to determine this information already linked in this thread. Hint: scopes have no accuracy on this topic.

People are going to take a **** in **** threads. Everything you need to know has already been posted. What the hell else do you want?
 
Not exactly, but close enough for practical purposes. When the field collapeses in some instances, where the pintle is stuck, the view on the scope will be slightly different. Very similar to this, but when you scope other injectors on the same vehicle you will see the difference.

Additionally, if you use a sensitive current probe you can see the pintle open. You won't see that monitoring the voltage unless you have such a huge resolution you can use the wiring harness as a shunt. As Kenny says, there's bugger all correlation between that and fuel flow because while you can see the open even you can't see how fast it opens and what the fuel does during the open event, but you can see the event itself.

****loads easier just to pull the injector and watch it open and close.

There is so much variation on dead time because it depends on temperature, battery voltage, resistance of the wiring harness, inductance in the wiring harness, differential fuel pressure, plus, plus, plus....
Each factor contributes a 10th of a gnats cock, but they all add up.

I always figured a flow bench was the way to get a starting point, and observation and tuning from there.
 
Pintle movement doesn't determine when fuel flow starts or ends. It's true that scoping current will to some extent track pintle movement, and it's a cool exercise. But, it still doesn't tell you where fuel flow begins and ends.

Using a flow bench to map delivery gradients, while a great way to determine the latency of the hardware itself still doesn't accurately simulate the dynamic operating characteristics in the injectors' environment.

The easiest way to determine latency, still, is to introduce a modifier and calculate the lambda differential as a result from the modifier. Takes no more than the vehicle and a laptop to determine, as long as variables are kept to a minimum during operation. Constant load around 50% duty cycle will usually yield the best results.

If Harald is complaining about an AFR delta of .5 across the operating range in open loop, other than determining the specific operating characteristics himself, I'm not quite sure what else he's expecting from other people's crap data.
 
Last edited:
The **** do you want, guy? Seriously. We don't own your car, you do. The entire reason Bosch, Rochester, Deka, et al don't publish how long it takes for the injector to deliver fuel from the time it's energized is because that information has nothing to do with their hardware. Many factors play into this, the entire idea already discussed by Kenny in this thread. The methods to determine this information already linked in this thread. Hint: scopes have no accuracy on this topic.

People are going to take a **** in **** threads. Everything you need to know has already been posted. What the hell else do you want?

In the simplest terms, anecdotal experience for a starting point so that I don't have to remap my VE table constantly until time is found to determine the actuals. Also,

1204-buddy-guy.jpg


Hey good mediation, Harribert!

index.php

I'll take it. It's been a ****ty car week.
 
In the simplest terms, anecdotal experience for a starting point so that I don't have to remap my VE table constantly until time is found to determine the actuals. Also,

So you have time to repeatedly update your VE table but no time to work on your deadtime compensation. Makes sense.
 
That's fine. Still isn't the place to be hate****ing each other. Not you Gary. Mostly ZVOLV, Nick, and Kenny. I love you guys but come on.

I don't hate anyone in this thread. I find various posts amusing for a number of reasons (author, content, etc)but in laymans terms I ain't even mad bro. It's just funny to me that now that zvolv has discovered scopes, everything he talks about involves using a scope, even when it's not necessary for a given task. They're great tools for a number of problems, but they're not the end-all be-all (just like a code reader isn't the ultimate diagnostic tool for obd2 cars). I suppose what that boils down to is this: it's a great tool to have (mine is indispensable when that's what I need), but the implied suggestion that you should have one to determine the info requested in this thread is a bit false economy-a $200 scope or $200 for brand new documented and flow balanced injectors. I'll use any excuse to add to my tool collection, but even that one is tough to justify (just for this particular issue. there is obviously greater future value in owning a scope than say $400 in timing lock tools if you only plan to change the timing belt once).


In the simplest terms, anecdotal experience for a starting point so that I don't have to remap my VE table constantly until time is found to determine the actuals. Also,

I'll take it. It's been a ****ty car week.

I posted anecdotal info in the thread as well in addition to things you can do to further narrow things down. The reason I didn't say "hey n00bz the opening time for that injector 355325060-352464646 is obviously .75ms at 12v bitchez" is a) I don't know the exact opening time for the injector referenced in the thread (but I bet I could get close on a wag, just from prior experience) but more because b) I would rather discuss how I go about determining a starting point for an unknown injector, as that is more universally helpful.

gotta wrap the post up, kid pooped.
 
why not flow the injectors to get your dead time like all of the other folks whom use MS. it takes at most 1 - 2 hours on the car pending on how much you can move your fuel rail around.

Here is a reference to one of the many threads that covers what is being done.

http://www.msextra.com/forums/viewtopic.php?f=131&t=41357

Search that forum for a bit and you may find the spreadsheet used for recording you data.

Finding that you need to do your homework if you want to play. Playing with others data is not always the best route with your given setup. In short you will spend more time chasing your tail putting in values that others claim to work for your setup. Take measure and calibrate your sensors and outputs before trying to tune.
 
Back
Top