My 383 TBI data logs

[nsxxtreme]

Did some recent data logging on the blazer, I was interested what some of you thought. I have the base timing set to 6 degrees. Idle is a little rough.
Still have a slight hesitation from when you go from low throttle and then floor it.
This is a 383
9.7 compression ratio
edelbrock etec 200 heads
edlebrock 7116 intake manifold
shorty headers
high flow cat and muffler, ypipe
54mm TBI 60lb injectors running at 21psi
aftermarket fuel pump
Lunati roller 60120 cam RPM 1600-5600; Adv. Dur. 262 Int./270 Exh.; Valve Lift .507 Int./.515 Exh.; Lobe Angle 112 Deg

 

[cuervo]

Looks lean on the low kpa side.

 

[nsxxtreme]

Looks lean on the low kpa side.

Changes will be made today hopefully that fixes it. I'll post up more data later. What are you looking at to determine lean? Felt a little lean while I was driving it also.

 

[big pappa b]

I look at those files and I feel like I'm in the matrix..haha

One day I hope to be able to decipher it

 

[cuervo]

The BLMs tell the story on rich/lean and 128 ideal and I see some 130+ numbers in the the lower kpa areas or 20, 30, and 40.

Numbers greater then 128 are lean, numbers lower then 128 are rich.

On the wide average, I assume wide ban average over time, you are lean up to 60s and in some cells you are 145+ which is very lean. I would think even dangerous over a short time if the motor is running hot.

With something this lean I would suggest a bump up in the BPW of at least 4 or 6 right now.

If you can post a screen shot of your VE table. I'm a rookie at this compared to Mark or Dave but I'm pretty good and knowing what to change to get results.

Likewise, your knock count says you could use some more timing until you get some knock then back it off a few degrees.

But, I would be MOST concerned with the high BLMs. Running a motor lean is easy death.

 

[nsxxtreme]

On the wide average, I assume wide ban average over time, you are lean up to 60s and in some cells you are 145+ which is very lean. I would think even dangerous over a short time if the motor is running hot.

Numbers greater then 128 are lean, numbers lower then 128 are rich.

But, I would be MOST concerned with the high BLMs. Running a motor lean is easy death.

Not hot at all. I have the 190 thermostat in there and it barely moves off of the 100 mark on the meter in the truck. I think water temps are in those tables also.

 

[cuervo]

Not hot at all. I have the 190 thermostat in there and it barely moves off of the 100 mark on the meter in the truck. I think water temps are in those tables also.

OK, but the 140+ BLMs are still a concern. I'd get those under control ASAP.

 

[nsxxtreme]

old VE table

new VE table

 

[cuervo]

What is the current Base Pulse Width Constant?

I see you ahve a Main VE and VE adder table.

Hopefully Dave gives you some idea on what to do with them. My current ECM only has a main VE table. Dave has suggested in the bast of combining the adder table to the main, but I've never done that.

 

[nsxxtreme]

What is the current Base Pulse Width Constant?

No idea where to even find that. I know both the VE table and VE adder is being utilized.

 

[dave w]

There are a couple different ways to adjust the VE Table. With the files posted, I would use the Wide Correction 10 Table from the BLM .txt file.

For example:
The BLM log shows: Wide # of samples for 20 Kpa vs. 1200 RPM is 128 samples. The Wide Correction 10 Table shows a correction of 1.109 for 20 Kpa vs. 1200 RPM.

According the screen shot of the old VE Table showing 20 Kpa vs. 1200 RPM is a value of 8.24. The Wide Correction 10 Table for 20 Kpa vs. 1200 RPM is 1.109.

The math is basic. Multiply the old VE Table value X the Wide Correction 10 value.

Example:

8.24 x 1.109 = 9.13816 so with rounding the new VE value for 20 Kpa vs. 1200 RPM is 9.14

I do not agree with the VE Table screen shot for 20 Kpa vs. 1200 RPM showing 12.16.

I recommend only changing VE values with more than 5 samples. In the example I have above, 20 Kpa vs. 1200 RPM has 128 samples.

dave w

 

[nsxxtreme]

New data from new tune

 

[dave w]

I looked at the logs. I think maybe changing the Base Pulse Width (BPW) might be needed. The logs are helpful, but I like using all the files that were in the computer when the data logging was done, (.xdl, .bin, .xdf, and .adx)

With 21 lbs of pressure on 60 lb injectors, the flow should be nearing 80 lbs / hr. Using the attach BPW calculator Excel spreadsheet with 80 lb / hr injector flow, the BPW should be near 103.

Everyone tunes differently. I set the timing to ZERO, and tweak the timing table. I combine VE 1 and VE 2 and then ZERO VE 2. I do all my VE calculations using Microsoft Excel. I feel Excel is the most accurate way to tune VE, but not many tuners use Excel. It's really a matter of personal preference. What one tuner does, might or might not be a logical tuning procedure to another tuner.

dave w

 

[nsxxtreme]

My BPW value is 140 I have no EGR valve.

I want to respect the tuner who is tuning my motor so I'm a little hesitant to post everything. I will ask him if he cares if I release it. If he doesn't care then I don't mind posting my bin. I'm going to let him go through his process then hopefully get it on a dyno. I know nothing so I'm not going to second guess him.

We tried setting the base timing to 0 and the thing would run like crap. Cold start was near impossible. Bumping the base timing up helped immensly. Really what I'm loking for at this point is how to understand the data logs. And what should be changed based on what's in the data logs. I'm just trying to learn.

I ran my truck through DEQ here and it passed but failed. We are only required to pass a sniff test at idle. I passed by the numbers but my idle while in park oscillates slightly.
HydroCarbon allowed =220 hydrocarbon actual= 179
CO Standard=1 CO actual =0.0588

 

[dave w]

My BPW value is 140 I have no EGR valve.

I want to respect the tuner who is tuning my motor so I'm a little hesitant to post everything. I will ask him if he cares if I release it. If he doesn't care then I don't mind posting my bin. I'm going to let him go through his process then hopefully get it on a dyno. I know nothing so I'm not going to second guess him.

We tried setting the base timing to 0 and the thing would run like crap. Cold start was near impossible. Bumping the base timing up helped immensly. Really what I'm loking for at this point is how to understand the data logs. And what should be changed based on what's in the data logs. I'm just trying to learn.

I ran my truck through DEQ here and it passed but failed. We are only required to pass a sniff test at idle. I passed by the numbers but my idle while in park oscillates slightly.
HydroCarbon allowed =220 hydrocarbon actual= 179
CO Standard=1 CO actual =0.0588

I am confused! The first post shows 60 lb / hr injectors with 21 PSI fuel pressure? I think a BPW of 140 is a setting for 60 lb / hr injectors at the stock 12 PSI fuel pressure. Anyway, the data logs show the BPW setting of 140 is close.

The logs posted look like WinALDL logs, which is OK software. I like using TunerPro RT to data log with. One of the features I like about TunerPro RT is the data log play back. It's very useful to replay a data log to review information.

Basically, to read the data log information is very simple. BLM numbers between 126 ~ 130 are good. BLM numbers that are not between 126 ~ 130 are bad.

dave w

 

[eagle mark]

Not hot at all. I have the 190 thermostat in there and it barely moves off of the 100 mark on the meter in the truck. I think water temps are in those tables also.

This means nothing when a motor is running lean. The valves and pistons will melt long before water temperature goes up. Lean produces much heat in combustion chamber where only oil cools pistons and air passing valves cool them.

We tried setting the base timing to 0 and the thing would run like crap. Cold start was near impossible. Bumping the base timing up helped immensely.

Which is OK as long as you add this value to Initial timing in chip/bin file. Which will take it off high rpm/top of advance curve. If not you will get knock/detonation or misfire faster then you can let off the skinny pedal. Usually a broken piston first.

Really what I'm liking for at this point is how to understand the data logs. And what should be changed based on what's in the data logs. I'm just trying to learn.

If you have an experienced tuner it can be done in a couple hours or a couple days if he finds no mechanical issues like not enough fuel for WOT, or vacuum leaks or? Learning to do this yourself from scratch will take months to years which can all be done without hurting a motor if you don't go lean WOT or have to much spark there.

 

[nsxxtreme]

If you have an experienced tuner it can be done in a couple hours or a couple days if he finds no mechanical issues like not enough fuel for WOT, or vacuum leaks or? Learning to do this yourself from scratch will take months to years which can all be done without hurting a motor if you don't go lean WOT or have to much spark there.

The adjustments are being made by an experienced tuner. I'm just posting the data logs and asking questions to learn. So if I ask a dumb question that has no correlation to the person doing the tuning. Because I'm not the one making the adjustments.

 

[eagle mark]

There's no dumb questions. Just holes in knowledge that need filled.

 

[nsxxtreme]

I am confused! The first post shows 60 lb / hr injectors with 21 PSI fuel pressure? I think a BPW of 140 is a setting for 60 lb / hr injectors at the stock 12 PSI fuel pressure. Anyway, the data logs show the BPW setting of 140 is close.

New tune data is attached. Yes the injectors are 60lb/hr and the fuel pressure is 21-22psi. He increased that BPW value to 150

The thing is starting run really really strong!! But also uses a LOT of gas I can almost see my gas guage move as I drive. I'm not driving normal either though. This thing is actually a blast to drive now.

 

[63chevyll]

It takes fuel to make power, so of your cam Is flowing the air, the tune needs to match. Easy right.

Also, are you running cats? Or A cat?.

I'm.not trying to sound like I know what I'm taking about because I am not a tuner, but I have tuned to a gas analyzer before and understand gasses.
But enjoy learning about this.