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Holden202T wrote:also another option if you wanted to, you can have two tunes on the nvram and just switch between them via the jumper on the nvram board! .... you'd need to have the car off to do the switch but otherwise no issues....

and you can also buy from the for sale section memcal boards which will allow you to use the same feature without having an nvram in there ... if you so wish that is

Holden202T, thank some useful info there. Another question, above Antus mentioned that you tuned for methanol using the AFR tables rather than VE. Would I be correct in saying:
- When you want to make changes to your tune that would apply to both petrol and meth you adjust VE
- When you want to make changes to your tune that would apply to meth only you adjust the meth AFR table

Thank you

yes and no

I started with a methanol tune from day one so I just changed all the AFR tables and offset tables to be 2.3 times that of petrol AFR tables then I tuned the VE from there.....

I do run it on E85 when not racing just because its easy to get from a local servo and cheaper than methanol etc .... and all I did for that was changed the same AFR tables for E85 and then uploaded the changed calibration and fired it up on E85.

its not perfect but then its a race car so I am not driving it every day to get enough time to get it spot on.

assuming your VE table is right for your motor and nothing else is out of whack like injector offsets and such, then you should be able to just swap AFR numbers in the tune and go from there.

as far as making changes to my tunes, I only ever change the one methanol racing tune that I have, for improvements in VE / Boost VE tables then if I do change them I just bring that over to the E85 tune I have by comparing the two in tunerpro.....

and I have two separate tunes as I use map a/b switching in my tune to change spark and AFR's when on the 2 step rev limiter, then when I let the button off I go back to map a AFR and spark and they are both methanol.

I also have a VL400 data logger in the car full time so I just have each of the tunes on the SD card and just upload as I need (20 seconds pretty much the change the tune over)

when I first started with methanol though I did play around with having map b as methanol and map a as petrol, and what I'd do is flush the system and then add petrol, and then start the motor and when it got really rich on the wideband I'd flick the switch to change to petrol AFR's and it would then just run as normal on petrol, and pretty much the same thing going back to methanol.

this was all with $12P

That's what I was hoping you'd say. I have just updated the stock $11P to suit deka 80lb's, and it starts/runs ok on petrol. I have then taken this tune and divided any afr's and injector rates etc by 1.5 to suit E85. It starts/runs ok on E85. What I intend to do:
1 - do a reasonable tune on Petrol (adjusting VE table)
2 - copy the tuned VE table to the E85 tune (this should get a reasonable result for the E85 tune)
3 - make any additional changes to E85 (VE table/injector rates)
4 - up timing for E85
5 - large burnouts

One last question, to disable BLM's do you use the flag "disable BLM's", or flag "force open loop", or both? This burnout car only so will NOT be wanting any fuel trim.
Thank you

pricemyster wrote:That's what I was hoping you'd say. I have just updated the stock $11P to suit deka 80lb's, and it starts/runs ok on petrol. I have then taken this tune and divided any afr's and injector rates etc by 1.5 to suit E85. It starts/runs ok on E85.

to clarify this. you can either leave the AFR tables alone and adjust the injector rate by 1.5 or you can leave the injector rate alone and adjust AFR tables by 1.5 so the AFR tables are showing E85 values. if you adjust both then your fuelling will increase by 2.25 times!

to clarify this. you can either leave the AFR tables alone and adjust the injector rate by 1.5 or you can leave the injector rate alone and adjust AFR tables by 1.5 so the AFR tables are showing E85 values. if you adjust both then your fuelling will increase by 2.25 times!

When I say different injector rates I mean upped the cranking BPW by 1.5 times and the kinflow changed minimally for E85 (from 0.035 to 0.037 - as per the spreadsheet calculator). I suspect the kinjflow for each will need to be fine tuned a little. I have not upped the injector rate by 1.5 (I adjusted the AFR tables).

Cheers

sounds fair to me

pricemyster wrote:One last question, to disable BLM's do you use the flag "disable BLM's", or flag "force open loop", or both? This burnout car only so will NOT be wanting any fuel trim.

Closed loop fueling has two fuel trims, BLM for a sort of long term learnt trim and INT for a short term or instant trim.

Set force open loop and all narrowband O2 sensor closed loop fueling is disabled, both INT and BLM will do nothing to trim the fuel. Disable BLMs just stops the long term trim from working, you still get the INT working to trim the fuel when in closed loop.

VL400 wrote:

pricemyster wrote:One last question, to disable BLM's do you use the flag "disable BLM's", or flag "force open loop", or both? This burnout car only so will NOT be wanting any fuel trim.

Closed loop fueling has two fuel trims, BLM for a sort of long term learnt trim and INT for a short term or instant trim.

Set force open loop and all narrowband O2 sensor closed loop fueling is disabled, both INT and BLM will do nothing to trim the fuel. Disable BLMs just stops the long term trim from working, you still get the INT working to trim the fuel when in closed loop.

Thank you sir, just what I was after.