Six_Shooter's "little" project v.240z

[Holden202T]

with the knock sensor DTC, if you don't run one set the "ESC params - Coolant temp enable" to 151 (max) which will mean the engine has to get to 151 degrees C before it enables.

[Six_Shooter]

Eventually I want to run one, but for now, I've left it not connected in the adapter harness, simply because I have the wrong sensor for the type of knock sensing system that the '165 uses. I'm going to look into it to see if the '165 can use the MEMCAL mounted knock filter, which would make things simple, external of the ECM speaking anyway.

[VL400]

So if the 20 to 100 KPA table will end up near 100 VE at 100 KPA, what good is the 100 to 200/300 KPA boost table then, if it's all going to be at 100 VE? This seems to suggest the $12P tuning doc is incorrect.

The VE of the engine does not always increase with boost, and if you have 90% VE at 100kPa its not 180% VE at 200kPa. You will certainly see some VE difference between the 100kPa column and all the cells in the 100+ region so thats why the the table is there.

So why have the boost multiplier? Just like the 20-100kPa region the ECU needs to know about the pressure changes. Run the engine at 50kPa and 100kPa with the same VE value, the fuel PW is different. The boost multiplier makes this happen at 100+ kPa by multiplying the fuel PW during the main calc, but rather than being hidden in code you can change it in 12P. Unless you have good reason to play with it it can be left alone.

[Six_Shooter]

So if the 20 to 100 KPA table will end up near 100 VE at 100 KPA, what good is the 100 to 200/300 KPA boost table then, if it's all going to be at 100 VE? This seems to suggest the $12P tuning doc is incorrect.

The VE of the engine does not always increase with boost, and if you have 90% VE at 100kPa its not 180% VE at 200kPa. You will certainly see some VE difference between the 100kPa column and all the cells in the 100+ region so thats why the the table is there.

So why have the boost multiplier? Just like the 20-100kPa region the ECU needs to know about the pressure changes. Run the engine at 50kPa and 100kPa with the same VE value, the fuel PW is different. The boost multiplier makes this happen at 100+ kPa by multiplying the fuel PW during the main calc, but rather than being hidden in code you can change it in 12P. Unless you have good reason to play with it it can be left alone.

This makes no sense.

I understand engine VE, let's just skip beyond that. Though I have NEVER come across an engine where the VE does not increase with boost. By definition the VE will HAVE to increase with boost, since there is more air being put into the cylinder than it could achieve naturally, so that's automatically greater than 100% VE.

What I'm being told here is that the vacuum VE table should be set up to have values that are near 100% VE at the peak. Then do something with the boost table that sounds a lot like fill it with those values at or near 100% VE, so why have that table at all?

FWIW, the only codes I've come across that doesn't have access to the boost multiplier are ones that have a poorly developed XDF/ECU files.

So how does the boost VE table get tuned then? Fill all rows with the 100 KPA values of the vacuum table? If that's the case why have the boost table at all?

In reading the 12P advanced tuning doc, it suggests that the max VE in the vacuum table will be well below 100% VE that will leave the ability to increase the VE numbers in the boost table. This is the only way that it makes sense to have these two tables.

I think I'm going to go with my idea of using effective displacement to get the kinjflow number that will allow values of less than 100% VE in the boost table.

[Jayme]

everyone has their own way of tuning, that is just their general opinion. and here is mine:
forget about getting to X VE number at 100 kpa... just pop in your target injector rate and go tuning, leave multiplier table alone and just work off the boost VE table. the angle of the boost VE table rising will depend on a few factors including your fuel reg etc, ive seen some engines that the boost VE will just keep going up as boost rises and some where the boost VE table will be flat as the boost rises. this is what I thought VL400 meant. of course the actual VE will be more as your boost rises but if your VE is 80% at 100kpa it doesnt nessesarily mean it will be 160% at 200 kpa.
the way I do it is if you hit 100 VE anywhere, then raise the injector flow rate by 10 % and drop the VE tables by 10 % and keep tuning. in my experience this happens more often in the Boost table.

[antus]

I think VL400 means the increase is not linear.

Properly tuned VE in 12P will end up looking something like this:
http://pcmhacking.net/forums/viewtopic. ... =10#p32266

You can copy the 100kpa column across as a starting point, but you'll see on the wideband that is not perfect and can tune the 100kpa+ VE tables to suit.

[delcowizzid]

so you end up with 2 tables like such you can see the shape of the torque curve in the ve table.dont worry about the fact that you are allready maxing out the ve you will lower the VE required with injector battery offsets which by rights should have the ecu one happy camper and allow for a nice ve table and consistant day to day fueling.how consistant well we run 11.1-11.3@120 down the 1/4 all day every day. hot lapping with no cool down we do 11.3 after 11.3 back to back as fast as we can drive through the pits LOL

vacuam VE.JPG

boost VE.JPG

[delcowizzid]

and yes you can plug on a memcal with knock filter board and wire the correct ohm knock sensor to the correct pin of the ecu and have knock control

[Six_Shooter]

everyone has their own way of tuning, that is just their general opinion. and here is mine:
forget about getting to X VE number at 100 kpa... just pop in your target injector rate and go tuning, leave multiplier table alone and just work off the boost VE table. the angle of the boost VE table rising will depend on a few factors including your fuel reg etc, ive seen some engines that the boost VE will just keep going up as boost rises and some where the boost VE table will be flat as the boost rises. this is what I thought VL400 meant. of course the actual VE will be more as your boost rises but if your VE is 80% at 100kpa it doesnt nessesarily mean it will be 160% at 200 kpa.
the way I do it is if you hit 100 VE anywhere, then raise the injector flow rate by 10 % and drop the VE tables by 10 % and keep tuning. in my experience this happens more often in the Boost table.

But this is just it.

the kinjflow calculator gives me a value that is less than what I am already using, and I am maxing out the boost VE table, and need more.

This is why I asked the question about using the "effective displacement" at twice the actual displacement when using 14.7 PSIG of boost, or scaled to whatever boost level I decide to go with. Using 14.7 just made it easy.

I'm trying to take a more methodical approach to using $12P, than I have in the past, with other code.

Lets get past the idea about VE being directly related to boost pressure, it's not, I understand that, we can move on from that.

What I'm trying to get here is a "proper" method for calculating kinjflow, instead of just fudging numbers until it works.

[Six_Shooter]

so you end up with 2 tables like such you can see the shape of the torque curve in the ve table.dont worry about the fact that you are allready maxing out the ve you will lower the VE required with injector battery offsets which by rights should have the ecu one happy camper and allow for a nice ve table and consistant day to day fueling.how consistant well we run 11.1-11.3@120 down the 1/4 all day every day. hot lapping with no cool down we do 11.3 after 11.3 back to back as fast as we can drive through the pits LOL

vacuam VE.JPG

boost VE.JPG

See, that's exactly what I'm thinking here, the 20 to 100 KPA table leads directly into the boost VE table, which requires values much lower than near 100% VE in the 20 to 100 KPA in order to allow headroom in the boost table.

Upon a second look, I see the 20 to 100 KPA table does reach 100% VE, but the boost table starts lower.

This makes it confusing in knowing whether there will be a smooth step between one table to the next.