2 BAR VE resolution poor

Hi All,

Working on tuning a friends turbo charged 6.0.
PCM/harness is an 03 Silverado DBW 4L80.
Green Blue connector.
OS is 12579405

I converted it to 2 BAR and expected a larger VE table. As was the case for my own car with 0411 PCM with 3 bar, the VE size doubled.
However, size remained the same. With everything crammed into the same number of rows.

Attachment 48468

This is proving difficult for me to tune.

Is there a better OS I could use to start with?
Will it flash into this 2003 PCM?
Is there a way to know what you get before changing to the custom OS?
What would a 3 BAR have done?

Anyway, looking for options here. I actually thought the 03 truck PCM had more RAM available.....

Ron

Welcome to P59.

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Originally Posted by DSteck

Welcome to P59.

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This^

I haven't found it to be a huge issue though. They tune and run fine with that resolution. Why is it proving difficult for you?

Ah, I didn't know this was a P59 issue.

I'm finding it very touchy to changes. If I see the fueling 10% off, and move it even 5% to correct, it overshoots badly.

My buddy has the Deka 80's in it as well. And although I have the Banish DVD data and disc, I'm not convinced it's correct.

My own turbo car with the 0411 and ID 1000's has been a dream by comparison.

Life got in the way for him, so I haven't touched it in 3 months. So wanted to ask this question before I get back to it.

Ron

The PCM interpolates between rows, not a big deal. Just don't copy-paste the changes into the VE table directly from scanner, analyze data first then adjust.
I have used several 80 Dekas and they are not known for it's accuracy and repeatability, yet they are great injectors for the price.

When we left off, it was idling happily and I got the 40kpa row decent through 3000 rpm doing as you stated. Analyzing the data making small tweaks.

We were ready to finally drive the car, winter arrived so that's where it sits.

I got volunteered for this job. If it were mine, I'd have figured it out by now. And I'd probably have just put a P01 controller in it.

Analyzing the data is the big thing there and then smoothing across known good cells. The breakpoints are 10KPa increments so if you are 4-5KPa off from the breakpoint you shouldn't use that data to manipulate the point that is 4-5KPa off from it. I've been spoiled with steady state dyno so I can hold engine load and RPM right over each cell to populate the cells to calibrate them. On the street I can see how this would be a little bit more of a pain.

One way around it is to manually setup your scanners VE table histogram to have 5KPa increments so that any data in between breakpoints fill in the middle cell that you wouldn't use. This would keep the cell boundary within +/- 2.5KPa.

Thanks James. Sort of akin to tuning the secondary VE in the 99-00 OS, using the scanner setup for the primary table.

We are going to finally get back to this on Sunday. We should finally be able to go for a drive.

A load bearing Dyno for steady state tuning would be sweet!

Ron

Drove the truck and made good progress. No surprises. Actually runs quite well.
Ron

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Originally Posted by RonSSnova

Drove the truck and made good progress. No surprises. Actually runs quite well.
Ron

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Sounds good Ron....guess the secret for the lack of resolution is to make sure you collect as much steady state data at the exact table break points to populate the ve table giving the pcm the best shot at accurate interpolation between them.

Ed M

For the P59s, I have custom breakpoint histograms to filter out data that doesn't really relate to what's available as James mentioned.

The only issue is vehicles that generate less than 30kPa MAP. You're outta luck in that region and destined to be rich.

Thanks guys. To get it into the ball park, I just had him drive it while I watched the chart display. So the first drives I painted some pretty broad strokes just using the histo data. Kind of fun to hear him say "that's way better" as it got into a happier range.
I had him be a bit more specific with rpm and time in the cells on the following, then worked on the rogue cells from a combination of what the histo said along with what I see in the chart data.
Still a lot of work to do, this is difficult in casual city driving as you guys know. Right now it's within 3% or so across the board.

Dave, got ya on the cells below 30 kpa. Turbo car, lift at the end of a pass, you know it's going below 30kpa! I guess it will have spare fuel to cool and lube the turbo there. :-)

He fired the truck up and drove it to work today. Considering that after his "pro tune" last summer, where the truck was completely un-drivable, and he was ready to give up and sell it, this is huge progress.

Ron

The other guys COS starts at 15kPa and goes in 5kPa increments.... What's up with that HPT?

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Originally Posted by PICNIC_GEORGE

The other guys COS starts at 15kPa and goes in 5kPa increments.... What's up with that HPT?

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On which OS?

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Originally Posted by PICNIC_GEORGE

The other guys COS starts at 15kPa and goes in 5kPa increments.... What's up with that HPT?

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Yes they have a seperate "Boost" VE table but it only goes to 285kpa as well. The other guys also don't have real time tuning with a P59 controller. Even the roadrunner doesn't work with the P59...

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Originally Posted by LSxpwrdZ

Yes they have a seperate "Boost" VE table but it only goes to 285kpa as well. The other guys also don't have real time tuning with a P59 controller. Even the roadrunner doesn't work with the P59...

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285>210 so that doesn't matter

There are 3bar OS's for the P59.... 320kpa...

http://i44.photobucket.com/albums/f4...v.jpg~original

As long as you know to filter the data, the resolution really isn't a big deal, even on the 3-bar OS choices you have 10 kpa increments for the normal driveability range, and then in boost 20kpa is more than enough to hit the AFR numbers correctly.

For 3 bar OS's, what are you guys plugging in for a filter string?