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Re: Injector dead time and pulsewidth

Posted: Fri Feb 07, 2020 4:41 pm
by craig903
I have a bosch motorsport one silver with a plastic end.

https://www.motorsport-systems.co.uk/do ... 650379.pdf

Re: Injector dead time and pulsewidth

Posted: Sat Feb 08, 2020 5:07 am
by stevieturbo
Those are extremely poor for air temp, as they are ridiculously slow.

As an ambient sensor they might be ok, but no use for charge temp.

Get an open bulb thermistor type. Cant recall part numbers with the same thread, but I ended up using the ATS04 as found on Cossies etc. They're cheap and very common. ATS04 is a spark plug M14x1.5 thread.

Although there probably are others with the M12 thread too like the Bosch.

Re: Injector dead time and pulsewidth

Posted: Sat Feb 08, 2020 7:45 am
by craig903
Okay, I've ordered the AtS04 sensor with an adaptor to put it in the silicone hose. We shall see on that one when it arrives,

In the mean time I have disabled closed loop lambda, OH MY GOD what a difference that has made. I'm going to just stick with driving and logging from now on and forget about the corrections etc spent days pissing about and the corrections seem to be the issue. I've attached the lambda settings I had for those who maybe able to spot something wrong and I Know the allowed correction is quite large at 20%/10% but it was a base map and things where far from perfect.

Re: Injector dead time and pulsewidth

Posted: Sat Feb 08, 2020 9:38 am
by stevieturbo
Never used closed loop to try and fix bad tuning. And for closed loop to work, the base map needs to be good, all lambda settings need to be correct for your install, and with small corrections allowed.

Closed loop systems are not some magic

Re: Injector dead time and pulsewidth

Posted: Tue Feb 11, 2020 7:21 pm
by craig903
So I've had a lot of good results. All seem to be going well. Replaced the IAT with a Marelli ATS04 Sensor. The sensor works a lot quicker.

Now I have another question. I have set out a 20 x 14 map compensation table and at the moment set the different pressures as per the ideal gas law. ie. 30kpa -70% fuel. Some of the cells in our main fuel table are accessed with different manifold pressures. Now what would I do in a situation where Lets say at 100kpa I want a target of lambda 0.94 but at 140kpa I want lambda 0.92. at 3k rpm and in the same load site. Would I simply just add 2% extra fuel in the map compensation table for that load site.

For example:

3000 RPM, 20% throttle, pulse of 4Ms but all 3 pressures below can access this cell.

80Kpa Target Lambda 0.96 : -18% compensation ( -20 as per gas law but we want a richer target so we don't remove as much fuel.)
100kpa Target Lambda 0.94 : 0% compensation
140Kpa Target Lambda 0.92 : 42% Compensation (40% required for the different pressure and 2% required to reach our richer target).

I hope you all understand what I'm on about. Thanks

Re: Injector dead time and pulsewidth

Posted: Wed Feb 12, 2020 3:10 am
by Rob Stevens
In the lambda parameters page you can change map or TPS as target 20x14 for the very reasons you mention.