Leeroy_25

Quick Question on timing with a rotary.. (20B running Microtech in this case but guess it makes no difference hence the general post)
Am I correct in thinking idle timing is usually up around the 5-10degs area. Should it then rise from idle until peaking out or is it common for it to drop before rising?
I ask as on my microtech I have got 7degrees in for 500rpm (idle) 0degs at 1000rpm, then 8 degs for 1500rpm and up. Hopefully image below. I think I added in timing at the 500rpm line originally to try and help engine pick back up to the idle cell which is 1100rpm. However I have since realised that with a working TPS the idle value of 7degrees is used for the timing. Regardless of idle rpm. I guess I could maybe add a couple of degrees in the high vacuum region to have the same effect?
I had a realisation the other day that this drop in timing at 1000rpm could be the cause of a couple of little on and off idle gripes I have been trying to solve.
So, I could do with a picture of idle area timing values and whether adding a bit in vacuum has any benefits before I just go ahead and fiddle!
Engine is standard porting (13B exhaust sleeves) and single turbo with 875cc primary injectors. As I gather porting would likely have an impact on the answer.

Thanks in advance!

chuyler1

iTrader: (1)

I only have experience with an Adaptronic on a N/A 13b but since you're looking for general feedback, here's what I have, which is very similar to the base maps provided for my ECU.

1) the timing map table never goes below 10 degrees.
2) the idle control circuit should adjust timing below 10 degrees once idle conditions have been met (more on this below)
3) timing rises similar to your chart at wide open throttle
4) timing is even higher, like 30 degrees, at partial throttle cruising RPMs but settles back down to 10 degrees at lower RPMs. I don't have this perfect right now so I still get some misfires. I need time on a dyno to get it right.

So Adaptronic idle control can adjust timing once it knows vehicle is not moving and throttle is closed. Since my vehicle doesn't have a speed sensor, I had to do this using digital outputs to override normal "closed throttle" logic. Basically I "AND" throttle position below 1% and RPM below 1300 and that is considered closed throttle and allows idle closed loop to take over. When idle control is not active, the motor revs at 10 degrees and 1100-1200RPM. Once it activates, it'll pull the RPMs down further by dropping timing to 0 degrees. I watched the timing on my stock 12a 1st gen and it behaves similar when you rev, there is a slight pause before RPMs drop.

armans

iTrader: (2)

Hey there,
Idle timing should be as low as possible as long as it doesnt stall the engine. Your timing to make a bump below idle rpm is a useful trick, personally I'd bump it even more to e.g. 20 degrees so whenever RPMs drop below idle range (e.g. engine choking by being too rich or the opposite) the engine would make more torque and kick the RPMs back to idling.
My old FT350 had similar tables to your microtech and I spent quite some time to have a relatively nicer idle (although I never fully finished tuning it as I replaced the ecu), my RPM compensation table looked like this:

Also note I didn't have IAC valve back then hence the this high bump below 800rpm.

And then the load compensation table looked like this:


As you can see my idle was at 6 degrees (10-4) (it is now lower because of IAC valve).

Just a note the boosted area (and anything above 2000 rpm if I remember correctly) is a break-down of the PFC base map (made a program to make two 2D maps out of 3D map by picking the lowest possible values etc, so the multiplication of these two maps (boosted area at least) yields PFC base map where some of the values are slightly lower (and others never higher) than the original PFC map).

Leeroy_25

Thanks for replies guys.
Armans there was not image of your table to look at.. This could be very useful. I do not have IAC either hence like you trying tricks to compensate that! and spending time doing so. Currently have to live with a richer idle to get around this.. but I feel there are some improvements still to be made. I tried to IAC control with microtech but could not get it to work at all which was annoying. Appears to either go wide open or closed and nothing in between. Most likely did not set it right but the user manual is a bit vague on the setup for this.
So back to timing. My idle is 7 degrees as per the rpm table. So sounds like maybe I need to drop this a couple of degrees? As noted above my idle is actually 1100rpm but when TPS trips into idle the timing is 7degrees. I guess it picks this value from the 500rpm line in the rpm chart as such how can I peak up the timing for when rpm drops below idle momentarily? I could maybe do something in the T_Map table. I think this is already up a touch in the higher vac regions by 3 degrees if I remember correctly? This will apply across the whole rpm range though so decel at high rpm would get the same timing increase?! As you decel down to idle rpm your vac also reduces though, So right before hitting idle you are pretty much back at idle vac so it might not work? Maybe I need to bring the 1000rpm line up to 7degrees and drop the idle line down to 3 or 5degrees say? or keep it the same if it does not like the drop. Then as rpm drops it should be very close to 1000rpm maybe a nats below but might linger in that higher timing area until TPS registers idle and the default 500rpm timing kicks in? I would have to drive and watch it .. But I suspect currently as rpm drops timing hits zero just before TPS-Idle kicks in and hence I get a drop off in rpm until it pulls back up? Also with very light throttle there is a little fluff which again I suspect timing suddenly drops as you knock TPS out of idle before rising with slightly more rpm. Just some hunches I have and want to know if I am heading own the right road and what my timing limits are. in vac, idle and just off idle. Curious to know if my 1500, 2000 rpm values are normal too. Seem to be from a few threads I have seen. Maybe 8 could go up to 10?

armans

iTrader: (2)

The two images I posted in my previous post has the idle related table values. I'm not sure if you're asking for some other table images...
In vacuum (or deceleration) you should have much higher timing than in idle. What your vacuum/boost table looks like though?

Leeroy_25

Hi Armans,
No not more tables.. the images you posted have not posted?? or at least I cannot see them.. Then looking further up I cannot see mine! Might be this computer. I will check on another device later. and try and post the T_Map table.

Cheers
Lee

Leeroy_25

Managed to view the images on my phone.. For some reason can't see them on my work PC. Anyway. First I looked at your RPM map and thought blimey those timing values are high! then I realised it subtracts the Load values from it! Will post a pic of my load map later as I did not get time last night.
So what units is the bottom scale of your load map in? Psi or inhg? You are surely not pulling 1bar vac at idle? I am getting about 17inHg on mine. so about -6.3 psi relative. I can see you have pulling the timing up below idle (I guess around 1000rpm?) quite significantly. So I clearly have plenty of margin in mine.
I think the issue I face with the microtech is that Idle timing works on the value set in the 500rpm cell regardless of idle rpm. So I think I have to bring my 1000rpm timing up level with the 500rpm line and then use values in the Map to pull extra timing until the point TPS kicks into idle mode. However I will always be at a point where timing is falling until it hit idle I think? Unless maybe I keep the 1000rpm value a little higher and then drop a couple of degrees into the 500rpm cell? I might have to play around and see if/what works. I don't want to end up with RPM lingering high and not dropping back to idle properly!!

Leeroy_25

Here is my T_Map screen. I also found an old T_RPM which appears to have 1000rpm set as 6degs. So I might try putting it back there first, It is from so long ago I don't know why for sure that value was dropped down.
I came across T_Inj MAP too anyone played with this???
Anyway feedback on my T-Map table please.
Thank you.

armans

iTrader: (2)

Yes my map was in PSI (even for vacuum range).
Your T_Map looks fine. Your maps overall doesn't look bad. The only strange thing as you say that it uses 500rpm value for idle while your car idles at around 1000rpm? That's really strange. Are you sure there is no other idle related settings there? I'm not really familiar with microtech software.

Leeroy_25

Thanks for feedback. So what vac are you pulling at idle? I will double check if anything else sets idle timing but I don't think so. If I get progress when I get around to playing I will let you know.

armans

iTrader: (2)

Mine is idling at around -6.9 to -7 psi.

Leeroy_25

Okay.. So I just spotted your timing map has an idle specific cell.. I am Pretty sure I don't have that luxury.. Gives you a bit more freedom with your settings.