Megasquirt with EFI Flywheel and CPS question..

[Karlos G]

... helping a mate fit MS to his EFI RS so we'll be using the existing CPS and flywheel setup. What settings do I use in MS, is it a 36-1 flywheel, what angle is Tooth 1 @ BTDC when the missing tooth is aligned with the CPS? Thanks!

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[xr2wishy]

spot on that fella, 80 degrees, same as mine.

[Karlos G]

Oh! lol
Thats just what mine happens to be, and i'm using a trigger wheel not the EFI flywheel and CPS.
You using EFI Flywheel and CPS yeah?

[JesseT]

it's a 36-1 wheel, and the missing tooth is aligned with the CPS when the engine is at 90deg BTDC.

[Karlos G]

[xr2wishy]

Originally Posted by Karlos G

Oh! lol
Thats just what mine happens to be, and i'm using a trigger wheel not the EFI flywheel and CPS.
You using EFI Flywheel and CPS yeah?

cvh efi flywheel and zetec cps, but it's in the same place as a frst/2i/3i one.

[Red_bull]

what injector timing delay are you guys running with this flywheel and CPS?

[xr2wishy]

Originally Posted by JesseT

it's a 36-1 wheel, and the missing tooth is aligned with the CPS when the engine is at 90deg BTDC.

really?
i need to get a strobe on my engine as i could be running way too retarded then.
all the settings i've seen for cvh/zetec are 80 degrees on other maps, hmmm.

[xr2wishy]

http://www.diyautotune.com/tech_arti...ford_zetec.htm

just had a look on that site and confirms 80 degrees.

[xr2wishy]

sorry for cluttering this thread, but i realised i had mine set to rising edge instead of falling edge, i guess the angle ATDC that the cps is positioned could be 90 degrees if on rising edge, seems way more responsive on the falling edge setting, but then there is 10 degrees approx between the two settings (360 degrees/36 teeth)

[JesseT]

You're talking about the #1 tooth, I'm about the missing tooth. So that makes a 10 degree difference...

[Red_bull]

what injector timing delay are you guys running with this flywheel and CPS?


Anyone?

[Karlos G]

What do you mean timing delay?

[Rob_DOHC]

sorry to ask a random question on your thread karlos, but has any one ever drilled a block to accept a cps?

Rob,

[Karlos G]

Think plenty of people have, you need a fuck off drill bit though! lmao
I'd get your local engineering company to do it for £20 save the ball ache of doing it yourself.

[Rob_DOHC]

May well be the way forwards mate, was a bit dismissive the last time i spoke to you about it, think the position is fairly critical and probably quite hard to be accurate, we shall see

Rob,

[Karlos G]

So long as it lines up with the 'Teeth' on the back of the flywheel it will be fine, the critical bit is how close the CPS is to the flywheel 1mm> or you risk dropping the signal at high RPM's.
If you have a CPS holder it will be easy to offer it up and mark the block.

[Rob_DOHC]

Doesn't its position, as in what angle round from tdc its at matter then? i know this can be changed in ms but would that mean having a good measure after its fitted???

Rob,

[Karlos G]

Yeah it can be changed easily, all you have to do is count the 'teeth' there is 36-1 so thats 10 degrees a tooth 36x10=360deg.

[Rob_DOHC]

Ahhh, simples, so count the teeth from sensor to missing tooth @ tdc and work out the angle from there.... Do you trigger on the rising or fallng edge karlos.

[Karlos G]

Rising edge mate.

[Rob_DOHC]

Cool, cheers buddy.

Rob,

[xr2wishy]

it seems it depends on firmware you use determines which you use, had a good look on diyautotune site for installing to ford zetec and for some it's rising edge and some it's falling edge.
i'm using code 2.1.1 extra code and that runs best with falling edge, where as on ms regular B&G code then on using edis you need to use rising edge.

i had no idea about this till this post popped it's head up again.

[Karlos G]

Rising/Falling edge refers to the voltage increase/decrease from the CPS so it either triggers as the CPS signals or as it stops signaling, code in the ECU shouldnt have anything to do with it, unless they calculate the timing differently?
Your calculated timing will be advanced (set to rising when should be falling), retarded (set to falling when it should be rising), or correct (set to what it should be) when checked against your physical timing (with a gun) and should be matched to it or your entire spark table will be wrong.

Unless i'm missunderstanding it....

[JesseT]

Originally Posted by Rob_DOHC

sorry to ask a random question on your thread karlos, but has any one ever drilled a block to accept a cps?

Rob,

I drilled an S1 block once for my Orion. Very easy enough because of the soft cast material. And you don't need a 30mm drill bit. I think I used 16mm as this was the biggest one I had. Then I used a step drill, and a rotary grinder as last. So, basically whatever I found. Was done with the engine in the car in minutes.
Everybody seems to warn about getting it dead right to the correct location. Bollocks, nothing will change if it goes a mm here or there. Even a huge 2mm error will result in less than a degree of timing error.

[Red_bull]

Originally Posted by Karlos G

What do you mean timing delay?

It's one of the general settings of megasquirt


Here's the discription of megamanual

Injection Timing Delay (InjStart): This is a user input in percentage after tach pulse that tells the controller when to start an injection event (i.e. a 'squirt'), and users can tune this to optimize the injection timing. Injection Timing Delay is a value that is a percentage of the number of degrees between injection events. Valid numbers are between 0 and 100 percent.
ANY NUMBER LARGER THAN 100 WILL PREVENT THE INJECTORS FROM FIRING. You must use a number LESS than the values below.
To convert the injector timing delay from the percentage used to crank degrees, multiply the injector timing delay percentage by these numbers:

• 90° for a 4 stroke V8,
• 120° for a 6 cylinder/4-stroke (even fire),
• 180° for a 4 cylinder/4-stroke.

So a value of 40% on a 6 cylinder gives an injection delay of 40%×120° = 48°. The injection will then occur at 48° after the tach event, or 48° - trigger offset (btdc).
Note this is a variable for injection start angle relative to the tach pulse (not necessarily TDC). The start of the fuel injection pulse width will begin at:

Tach time + InjStart % × predicted delta_t (between present and next tach pulse)

which is in crank degrees. When that time is exceeded in the main loop, MAP is grabbed, the pulse width is calculated, and fuel is injected in that sequence.
Now because MegaSquirt® does not do sequential injection (though the MS-II Sequencer™ controller will), it won't squirt at the same point in the engine cycle for all the cylinders connected to the same injector driver, but by moving the injection timing delay around you may be able to improve your idle. There is no simple calculation to come up with the best number for you to use. The general idea is to avoid injecting into an open exhaust valve. Since MegaSquirt® controllers use a banked injection system, then it would be better to move the timing on all the cylinders to a place where it avoids this on all cylinders (or as many as can be accommodated).
What you have to do is adjust the injection timing delay from 0% to about 80% and see which value gives you the best idle - as determined by the highest vacuum, or leanest AFR, or smoothest idle, or whatever else you are tuning for.
Of course there is a limit - you can't inject at say 98% of the next predicted tach pulse interval because there may not be time to calculate it all. Plus there is bit more fluctuation in fuel timing - NOT in the overall fuel pulse width, which will still be interrupt driven and exact, but in when the injection starts. This could vary by as much as a few milliseconds at low rpm, but the idea is that it is way better to inject within +/- a few ms of optimum than to consistently inject at a non-optimal value. However, to ensure there is plenty of time to calculate the PW and start the injection, the fuel start time is limited to force it to occur at least 2 ms before the predicted next tach pulse. So if you look at a scope you will see the fuel pulse move right relative to the tach input as you increase InjStart %, but it will stop when it gets within 2 ms of the next tach in pulse, regardless of your increasing InjStart %.

[Karlos G]

Ah you are MS1!!
I have not used that so never seen this setting before.

[Rob_DOHC]

Originally Posted by JesseT

I drilled an S1 block once for my Orion. Very easy enough because of the soft cast material. And you don't need a 30mm drill bit. I think I used 16mm as this was the biggest one I had. Then I used a step drill, and a rotary grinder as last. So, basically whatever I found. Was done with the engine in the car in minutes.
Everybody seems to warn about getting it dead right to the correct location. Bollocks, nothing will change if it goes a mm here or there. Even a huge 2mm error will result in less than a degree of timing error.

Brilliant, thank you very much

Rob,

[Red_bull]

Originally Posted by Karlos G

Ah you are MS1!!
I have not used that so never seen this setting before.

No i'm running MS2, i will make screenshots of it. It's a setting that's also on ms2