SOLD - 1600 TURBO + oval + downunder

[Piledriver]

at 80 KPA and below (I use a sharp 90/92KPA row transition) you should have a large cruise area at at around 17:1,
This will drop your cruise CHT and improve economy significantly, you likely spend most of your time there.
Mine runs from 2600 RPM to redline, and from 90 KPA down.

30KPA is usually hard into fuel cut, its arguable if that row is better used higher up the map.

Do know that you can use two maps "stacked" to (almost) double your resolution.(works horizontally too)

You need to go to best power AFR by 100 KPA, usually 12.3:1 or thereabouts.
This will transition you into boost properly.

My NA setup "switches" rich hard at 92 KPA.

Note stock (factory) AFR at WOT was around 11:1 to provide plug cooling....

You can also "get some of this" with a MS2E/MS3 feature called "load/time enrichment", which GM and everyone else uses on anything boosted, starts off at target best power AFR and adds fuel over time if you stay in it simply so your plugs don't melt. I asked for that feature because aircooled engines truly need it, boosted or not, and the MS devs amazingly implemented it in days, as it really is a feature for ~any setup.

The timing map will need a bit or corresponding massage as you'll need 3-5 degrees more timing at 17:1, as the burn slows down, and less at 12.3:1.

[Clonebug]

My suggestion was to set it at 14.7:1 in those areas for now......once the tune is stabilized you can then tweak the cruise areas leaner if desired.....

You have some serious lean areas in the real low kpa bins which make your AFR's spike to 19:1at high vac conditions or when shifting gears.

My tune has an annoying lean spike when shifting and when decelerating and then going back into the throttle lightly. I would guess that yours would be worse with those really lean bins........you never know ...every engine is different.

I haven't had a chance to hook the computer up and fix it yet......

[Piledriver]

Running at ~stoich generally causes the highest CHTs, and should be avoided on an ACVW unless you have to run a catalytic converter, which requires it.

[petew]

Oh man PD, you've given me sooooo much to think about there.

at 80 KPA and below (I use a sharp 90/92KPA row transition) you should have a large cruise area at at around 17:1,
This will drop your cruise CHT and improve economy significantly, you likely spend most of your time there.
Mine runs from 2600 RPM to redline, and from 90 KPA down.

30KPA is usually hard into fuel cut, its arguable if that row is better used higher up the map.

Ok, so this is a new things for me. I must admit the thought of running 17psi on much of the map sounds a little concerning. However, I also know that OEM tune is often in this range for all the reasons you've mentioned above.

I also know there's light and shade in there that has to be found. For now I still feel like I'm finger painting.

I'm about to drive the car 600km next weekend. I'd like to make these sorts of changes BEFORE I leave and start autotuning. What I'm trying to avoid is burning holes in the pistons.

Do know that you can use two maps "stacked" to (almost) double your resolution.(works horizontally too)

I've heard about this from CB, but I seriously have no idea how to do that. I'd like to have a go though.

You need to go to best power AFR by 100 KPA, usually 12.3:1 or thereabouts.
This will transition you into boost properly.

My NA setup "switches" rich hard at 92 KPA.

I've been trying to get this right, although your advice today has widened my scope considerably. Would you suggest the same thing in my maps? As you suggested I can easily pull the 30kpa band out.

Note stock (factory) AFR at WOT was around 11:1 to provide plug cooling....

Ok, so this kinda scares me more than a little bit. I've not fouled or melted a plug with this motor yet. So I must be doing something right.

You can also "get some of this" with a MS2E/MS3 feature called "load/time enrichment", which GM and everyone else uses on anything boosted, starts off at target best power AFR and adds fuel over time if you stay in it simply so your plugs don't melt. I asked for that feature because aircooled engines truly need it, boosted or not, and the MS devs amazingly implemented it in days, as it really is a feature for ~any setup.

Is this available to me in MS3 with a microsquirt? I looked up MS and found load based acceleration. Is that what I'm looking for?

The timing map will need a bit or corresponding massage as you'll need 3-5 degrees more timing at 17:1, as the burn slows down, and less at 12.3:1.

Like I said before, keen to do this. But I don't want to do any damage. My other issue is I can't hearing the motor detonating. I can feel it, but not hear it and by the time I feel it, it's probably been happening a while.

[petew]

Alright PD, so I drew up a new tune and made the changes you suggested in the AFR and Ignition tables. Can you have a quick look and make sure I'm on the right track pls?

PDsupgrades AFR draft 1.jpg

PDsupgrades Ignition draft 1.jpg

[petew]

Here's the new VE table BTW... Obviously it's yet to be tuned properly.

PDsupgrades Fuel VE draft 1.jpg

[Piledriver]

Looks much mo betta.
But:;You need a LOT more timing at lower MAP and lean AFRs.
I'll post my current tables as soon as the laptop boots...
To use multiple tables, you use table switching.
(there are very good instructions in the online manuals)

...and "load based enrichment" is what they called the feature, its actually time vs load.
I use it over 92 kpa, note for the hard switch you need a 90 kpa row.
The MS interpolates very well, this is to avoid that.
Also note you can (ab)use the WUE and cold timing features over the full temp range (to 450F) to add fuel and pull timing as CHT heats up.
"aircooled extended temp range" option must be set under "gauge and settings limits"

Also--use idle ve and idle timing features, I think ms2/uS current firmware has both now.
keep idle settings off the main tables.

For your amusement:
You have a t1 so you probably need a tiny bit more timing, and 20:1 is really pushing it on most engines.
I run into lean misfires at ~23:1, and the WBO2 calibration is correct vs. serial readout. (14point7.com JAW v1.03 reads 10:1 to free air)
Theres a bit of noise in my VE table as I redid it from scratch for a "new" WB sensor and controller recently.
(reinstalled the old JAW)

afr-target-pile-ms3.png

timing-table-piles-ms3.png

ve-table-piles-ms3.png

[panel]

Pete , there is a lot of good target AFR table stuff here:

viewtopic.php?f=23&t=132530&hilit=afr+table

viewtopic.php?f=66&t=148487&hilit=afr+table&start=15

[panel]

http://www.autoworks.com.au/cms/blog/15 ... -sensors-3

[Piledriver]

Best efficiency at cruise is (theoretically) at ~17:1 AFR, and you should be able to pull it with a few degrees of additional timing. The burn is slower, so it needs it.
This will run cooler, and will require slightly more throttle, which also helps efficiency.


(diesels and some latest GDI engines have no throttle (older GDI have one for idle but try not to use it),~ all fuel control, this and higher allowable compression is largely where the better fuel efficiency comes from)

[petew]

For your amusement:
You have a t1 so you probably need a tiny bit more timing, and 20:1 is really pushing it on most engines.
I run into lean misfires at ~23:1, and the WBO2 calibration is correct vs. serial readout. (14point7.com JAW v1.03 reads 10:1 to free air)
Theres a bit of noise in my VE table as I redid it from scratch for a "new" WB sensor and controller recently.
(reinstalled the old JAW)

afr-target-pile-ms3.png

I literally roared with laughter when I saw the 20AFRs! The ignition map also made me laugh hard.

This is really awesome stuff and is specifically why I wanted EFI in the first place. It totally changes the efficiency of a motor.

[andy198712]

My motor didn't like going above mid 15 at cruise, got bucky and rough but I was only moving fuel table, it's about balancing that and ignition as I learnt, and you can't do that to this level without efi, totally agree with you Pete!!

[panel]

Found another related post...

http://www.shoptalkforums.com/viewtopic.php?t=142739

[petew]

Had the car out this morning with PD's suggestions installed. I was concerned about the effect it would have on CHTs. I needn't have been. It ran coolest at 17AFR at 2600rpm. Still got a lot more tuning to do, but I feel like I'm on the right track.

[Piledriver]

Cool.
(literally )

There was a mention of aircraft techniques re: leaning the mix for economy...
You must keep in mind 3 things:

They basically run at ~one speed/load, with little variation.
The classic (and still valid) EGT based leaning procedures were developed with carbs (with uneven, (sometimes horribly so) fuel distribution), and fixed timing, thus the "rough running when leaning too much".

They usually don't even have an advance mechanism other than a retard for start up.
Sometimes.

Its a whole different ballgame when you have uniform A/F mix and distribution, and basically can freely time ignition advance as required at any load/RPM.

An EGT gauge is useful for finding best timing, but it may screw with you...
remember, too much advance drops egts, retarding raises them.
Whats ideal? whatever gives lowest CHT? (or best power/efficiency) for a given load?
I go with CHT, as its a direct function of the latter, it's logged by default, and I have a fast response CHT setup.

Note a few degrees too much advance (at light loads/cruise) hurts the efficiency far less than a few degrees retarded. (there's a paper by Toyota or such that beats that to death with a spoon)

It also lowers EGT and MAY lower CHT.
No knock, no foul.