VE estimation for boost

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CHB
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VE estimation for boost

Post by CHB »

our MS2 fueling equation "PW = REQ_FUEL * VE * MAP * E + accel + Injector_open_time" is it possible for us to estimate the VE value at certain RPM/kPa?
here is an example. now at 5000RPM/200kpa, my VE is 80 in which i can obtain 12AFR. if i'm going to higher boost, let say 5000RPM/300kpa and to obtain the same 12AFR, can we come out with certain constant factor in which we can multiply it with our VE value at 5000RPM/200kpa?
my issue raised because we hardly maintain at highboost for a period of time where we can actually tune out VE bins.
devastator
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Re: VE estimation for boost

Post by devastator »

In theory you could calculate the VE values. If you're running a RRFPR, I think you'll see that boost VE values are not much different than the values at 100 kPa. My VE values are around 97 at 175 kPa and 90 at 100 kPa with a RRFPR.
CHB wrote:my issue raised because we hardly maintain at high boost for a period of time where we can actually tune out VE bins.
Try using MLV to tune this area. I did and it tuned in nicely as I also only see boost for 3-5 seconds max.
Sandrail-ACVW 2276 cc, Turbo
MS-II W/spark burning E85
The sand must be punished. :twisted:
CHB
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Re: VE estimation for boost

Post by CHB »

yes i'm using SARD 1:1 boost reference fuel pressure regulator. its kinda hard to use the MLV to do the VE analysis as we need to load the Fuel VE everytime we done an analysis. another thing is during a road tune session, if we are in the Fuel VE map, we cannot see the AFR gauge update at behind the VE map. can i monitor the AFR gauge in MT while tweek the VE bins up and down at the same time?
devastator
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Posts: 333
Joined: Mon Feb 11, 2008 10:19 am
Location: Kinda near Tucson Arizona

Re: VE estimation for boost

Post by devastator »

CHB wrote:its kinda hard to use the MLV to do the VE analysis as we need to load the Fuel VE everytime we done an analysis.
It is time consuming but worth the effort IMHO. This is the reason I mounted a touchscreen computer in my sandrail.
CHB wrote:can i monitor the AFR gauge in MT while tweek the VE bins up and down at the same time?
Yes, under Tuning - VE Table 1 (map).
Sandrail-ACVW 2276 cc, Turbo
MS-II W/spark burning E85
The sand must be punished. :twisted:
CHB
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Posts: 19
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Re: VE estimation for boost

Post by CHB »

thanks a lot dude!!
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