Optimum Spark Tuning for the E40 /LS2

[Gelf VXR]

CALC.POWER_RW pid from my experince gives garbled results.

There is another pid GM.TORGUECALC_DMA, if this pid provides consistant data then it can be mapped against SAE.RPM and GM.APCYL_E40_DMA in the same way GM.KR and SAE.SPARKADV.

This method can be used to monitor effects of changes made to timing on the calculated torgue map comparing before and after results, and in the same way tune optimum spark as if you where using a rolling road Dyno. Advance spark until no further increase in torgue, a few more degrees should see torgue reducing and the onset of knock, retard back a few degrees or to the mid point where max torgue was seen.

Of course you may want to use a RR to verify the results.

Also unless you have hours of Dyno time, WOT timing is all that is optimised, this method tunes the whole spark map and for street use.

Has anyone tried this?

[stigmundfreud]

not tried this but would be willing to give it a go on my ls1 (which will be different mapping)

got more details on what you are doing gelf?

[Gelf VXR]

not tried this but would be willing to give it a go on my ls1 (which will be different mapping)

got more details on what you are doing gelf?

I'm setting up torgue map with rows = SAE.RPM and Columns = GM.APCYL_E40_DMA, which is the same as the Hi octane map. Its probably a good idea to start the process by copying the low octane table over to the hi octane table. This way you should definately be seeing increases in the calculated torgue, so you know your on the right side of the peak torgue curve and hopefully no knock being logged.

B5101 and TORGUECALC maps



My plan of attack:

AutoVE smoothed to within +/- 2% average of both banks

Lowered PE throttle threshold and set my desired PE AFR (13.5:1-13.1:1)

Set up lean cruise (15.4:1) in low kPa cells in OL load multiplier table

Determine whether recorded knock is real or not. I believe that Monaro's in the UK are set up for use with low octane 95RON fuel, I always use 97/98RON

Start by logging the average calculated torgue of low octane map to get a base line reading, save into excel, increase timing incrementally up to the high octane map saving and comparing results with previous each step of the way, keep adding timing until torgue starts to drop and revert timing back to where peak torgue was seen.

Filters will need to be applied so to capture cells that are between cruise and WOT only, no deceleration cells required.

[stigmundfreud]

are you doing too much before completing ve or have you done that now?

Interested in lean cruise - did you go via the route richard did with the commanded table (COS) or did you enable lean cruise?

I think it would be interesting for you to go down to Vixpy's and get a base dyno run then do your changes and guage the result! I need to get back down to his to see how things are different now the cats are in place and I'm commanding 13.1 pe instead of the 12.5 last time.

The timing map I am running is the hsv one and I get next to no knock at all other than a 1 or 2 degree at 6200 but the count is low so putting it down to the fact the sensors go a bit crazy at high rpm.

[JezzaB]

What you will find on the dyno is that KR can be a long way from MBT (Mean Best Timing)

[Gelf VXR]

are you doing too much before completing ve or have you done that now?

I will be on my seventh logging session, I've only just started using filters, hopefully my BEN's will settle close to zero now. With BB logging, it will probably be an ongoing process of tiny adjustments.

PE and lean cruise shouldn't affect my BEN's, only in transtional states which I'm filtering out.

I don't have C03 or lean cruise enable calibrations. What I do have is 3 open loop fuel calibrations, in the load calibration I can set the commanded fuel to 15.4:1 in the low rpm and map cells. You can even set up PE in the higher cells if desired.

I want to tune spark advance map for my desired / commanded AFR's. If you change your AFR's, I believe you will need to retune your spark advance map to suit.

I have a base dyno plot for stock set up, all I've had fitted since is a wortec cat back without remap.

The knock I'm seeing 4-5 degrees at 1800rpm and 0.6 grams per cyl is at 95 kPa and questionably PE was not enabled??? PE map below

[stigmundfreud]

yes aware of the different ways you can command the afr but thought you had gone custom OS.

my personal view on things is to do each bit at a time rather than relying on filters. Ok it takes longer but you are purely doing one bit at a time. timing can adjust the afr readouts (which you know about) but I'd rather tune the ve. Then tune the timing after.

[Gelf VXR]

yes aware of the different ways you can command the afr but thought you had gone custom OS.

my personal view on things is to do each bit at a time rather than relying on filters. Ok it takes longer but you are purely doing one bit at a time. timing can adjust the afr readouts (which you know about) but I'd rather tune the ve. Then tune the timing after.

The options for custom OS is limited with the E40, I have upgraded to custom OS, this allows for FI and hi and lo octane tables with SD.

I spend 5 weeks at a time away with work, plenty of time for theory. I am still only at the VE stage. My thinking is miles ahead lol

I wont be touching my timing, I'll need to log and see what results the TORGUECALC pid gives before i set down that route

[stigmundfreud]

Oh yeah I forgot to replace my low timing table, I'll do that tonight. Looking at the lean cruise option too but getting good mileage anyway.

You certaintly have been doing a lot of theory stuff!!! Weird about the low down knock though!

[Gelf VXR]

Oh yeah I forgot to replace my low timing table, I'll do that tonight. Looking at the lean cruise option too but getting good mileage anyway.

You certaintly have been doing a lot of theory stuff!!! Weird about the low down knock though!

How did your MOT emissions go?