can someone cast an eye over my VE table

[Cairb]

So with hybrid do I use map at low throttles and move to alpha N at higher throttles?

No, I showed the VE tables for SD and hybrid alpha-n for comparison. These were generated from an analysis application that generates tables for both algorithms.

I don't blend both. I did modify the software at one point to run in this 2 table mode where it used SD below a certain map then switched to the alpha-n but thought that I may be over complicating things by having to modify 2 tables.

The hybrid aspect is in that the pulse width calcs multiply the VE from the table by the MAP from the ITB's. This is where I think that it may require to multiply by a value that depends on MAP but not linear. I'm using a modified version of MSns-E version 021u, I believe that other versions may work slightly differently. Also, I think that others have used atmospheric pressure rather than MAP in hybrid mode.

Would a more progressive (non linear) throttle linkage help or am I looking for an over simplistic solution?

I can't see that the throttle linkage has any significance on the fueling, it's more for driver control.

Jedrik - I found that a 3D plot of MAP v RPM v TPS that can be viewed from different angles helps to visualise the relationship. If you pm me your email I will send you a datalog.

Colin

[whittlebeast]

Have you ever thought about MAF. It realy makes finding when the airflow realy starts to come on way easy to find.

AW

[Cairb]

Have you ever thought about MAF. It realy makes finding when the airflow realy starts to come on way easy to find.

AW

My arrangement has 4 ITB's with a sausage shaped filter protruding through the bonnet so it doesn't really lend itself to MAF.

I think that some of the variation of MAP at constant TPS and RPM is due to changes in engine load which in turn means an change in air mass flow which needs a change of fuel, which is why I am trying to use the MAP to vary the fuel at a given TPS and RPM. It's just that I have a feeling that the variation with MAP is non linear as borne out by the shape of the SD VE table.

Colin

[mops]

quick non-trlated questin about ITB's.
from where do you take map reading ??? i mean there's no mainfold.... as we know it... do you just take a reading behind one of the throttle valves ? if yes doesnt that pulsate alot ?

[whittlebeast]

Typicaly route all 4 intakes together with 4 small hoses all T'ed together and then run to the Squirt map. You can add restrictors (fish tank air control valves) and volume adders (fuel filters) between the T and the Squirt

AW

[jonfx4com]

Fascinating thread! It was only when I added a mechanical vacuum guage that I realised that just T ing all the ports together was not giving me a smooth MAP reading, the needle dances around the guage. Have added a fuel filter and that helped a lot. Still finding that most of my driving over 50Mph is in the 90-100Kpa range. Even 35Mph cruising is in high 80s. Runs very smoothly though so its just a matter of tweaking. Will save my MSQ in case of disasters and then have a play with alpha-N this weekend. AE is an issue though, waiting for the new x-tau code, sure that will help, its a much better system even if it does take a little more understanding that just squirt some in when you hit the pedal.

Having all kinds of problems with EDIS, I can change the trigger offset from -20 to + 20 and it still runs the same, only the idle quality changes but I know the advance (saw) works as when I move the numbers around the engine idles different. Will have to get out the scope and timing light I think as I am stumped at the moment.


Jon

[whittlebeast]

If you are running Extra code then grab the o26h4 code and use RPM based AE. If you are running ms2 then 2.62 and later for x-tau or the new normal AE will help.

see http://www.msefi.com/viewtopic.php?t=16087

AW