Re: 7749 guru needed....

[Scot Sealander <Sealand@clarityconnect.com>]

Green wrote:

> Changed that as well;  there's a calc that computes the fake 1 bar and
> checks for overflow. Basically had to get new constants in that calc to take
> ~ 1/3 of full range for vac, rather than ~1/2 from the 2 bar.  I believe
> this is the only part of that code section that needs changing ?

No.  The MAP in kPa calc should be changed also.  Last I looked, the 
3 bar MAPindex had not beeen re-scaled.  Some of this is just how
"correct" you want to be in your calculations.  It can be made to work 
with fewer changes.


> So the big code change i made was the 3 bar to vacuum calc.  The changes in
> the tables portion of the chip are extensive also.

Most of this should have been minimal, except the main spark table. 
That 
depends on how you decide to re-scale the 3 bar MAP index.  I re-scaled
it
to 15 kPa steps.  Have never run the code though....  No SyTy. ;-)  I am 
working on getting to 3 bar for my turbo vehicle, but the ONE bar area
needs to 
be correct first.  Getting that just right takes a lot of time.  (Closer
and
closer.)


> The 2 tables (open throttle and closed)  now have a bit less resolution; not a 
> big deal at idle, but at open throttle, you only have like 2-3 lines of table 
> in vacuum, for drivability tuning.

A wrong assumption here somewhere.  The variables that address the VE
tables 
stay the same, if the 3 to 1 is done correctly.  (All in one bar
territory.)


> The closed throttle table wastes a 6x9 table space of low RPM from
> vacuum to 3 bar of boost ! 

Same as above.  The table works just like it did before with the 2 bar.
All in one bar!


> So i'm hoping to change the way the VE tables are setup now.  Maybe make one
> for drivability, that uses vacuum, then make the other in use during PE mode
> only, using full range ..? I'm not sure yet.

You already have the 20 to 100 kPa tables now.  You could add a two axis
table for VE changes above baropress.  These values may be harder to
determine
though!

Scot Sealander
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