Back to Back Datalogs of 3100 and 3400 on OBD 1.5

[snowblindburd]

Lol it was running on good ol' 87 octane.

15.611@88.51MPH

[wicked-irocz]

No you can't physically change the duty cycle but you can drop it buy adding in supporting mods such as larger injectors or a higher fuel pressure if using 2000+ injectors, I know its a driven value not a drive one.

I was trying to imply that we can't tune the OBD 1.5 and since it is speed density the computer never even realizes that its running lean when at WOT since it reverts back to 128/128 and no longer corrects the fuel trims. I also think it would be nice to look at a MAF car like this since the MAF would detect the higher volume/mass of air.

You have any 96-99 3400 injectors Mark?

I'll add your time later tonight when I have access to uploading online.

[3X00-Modified]

I was trying to imply that we can't tune the OBD 1.5 and since it is speed density the computer never even realizes that its running lean when at WOT since it reverts back to 128/128 and no longer corrects the fuel trims. I also think it would be nice to look at a MAF car like this since the MAF would detect the higher volume/mass of air.

Correct, But you can work around this buy upping the injector flow rate physically... Because the now the ECM thinkgs they only flow X amount at X Pulse Width and obviously if you bump up the X amount and the PW is the same then you would end up with a richer mixture.

This is why I never spent the time to figure out how to datalog OBD1.5... I knew it would just make me mad to see stuff I couldn't adjust for

[woody90gtz]

Lol it was running on good ol' 87 octane.

15.611@88.51MPH

Boooooooo.

[snowblindburd]

Lol!

Dusty- I may have a set of the original injectors (from the 3400) in my backpack. I would have to have you take a look at them to verify what they are though.

[IsaacHayes]

Gear selector is easy. The actual gear would need two different inputs mapped to one thing in TP, but there isn't a way to do that. You can just have two things show if solenoid A or B is on or off, and just figure out from there....

When I get some time I will compare ours both and see what's wrong with mine. That may be a few weeks off. My code section works perfect. You gotta connect with a different mode of course.

What seems wrong about the TCC slippage one? Mine seems about right I would guess...

Jon, yeah I noticed all the KR too.. WTF is up with that?? I do not have any KR and my engine is modded. Sure it's not a 3400, but I've got bigger runners, plenum, TB, and exhaust.

[wicked-irocz]

Yeah, Jon I know.


Issac, we discussed many times here that too small of an injector combined with low octane is likely causing the knock. Hopefully you figure the transmission stuff out before I do so I don't have to mess with it. Anywhere from 5-35 RPM of slippage is not correct. The TC slips much more than that. Its slipping up to 2100 rpm on my car and the readings should reflect that but they don't.

[IsaacHayes]

I used to get knock when we had straight gas with 87 octane in hot summer (stock motor). Then my timing was pulled cause it was un-responsive and I heard a slight ping. With my modded stuff I have no idea if it would still ping or not. Then I started running 89 and it was enough to curb it and throttle response was up same for MPG. Now by law it must have 10% ethanol (mpg hit right there) so even the 87 octane is really 89 cause it bumps it up. That's why here they sell the 89/87 for the same price cause it's the same stuff coming out of the pump.

When I was logging I was recording more slip than 35 rpm.... lol.... I'll have to dig my laptop out... Did you check out my scanner pro stuff? That works and logs perfectly but it doesn't do CSV export just play back but you can have analog gauges which is helpful playing back real time and looking at stuff. I haven't checked for a new version in forever. It was in beta when I used it.

[3X00-Modified]

More slip that 35 RPM? Yeah I would expect that unless the converter is locked... unlocked you will get way more than 35rpm slip. Locked, well um, I'm not sure how low it actually can get...

[wicked-irocz]

It can go positive going down hills

I have never used scanerpro

[3X00-Modified]

Lol it was running on good ol' 87 octane.

15.611@88.51MPH

Oh yeah I did 13.996@98mph on 87 octane LOL

[IsaacHayes]

Yeah when you left off or go down hills it goes -9000 or something
I'll have to pull my laptop out this weekend and do some logging. Sunday I'm thinking. I should have the battery and hub replaced, and sunday I can wash it, and adjust the sway bar and then go for a cruise.

[snowblindburd]

Lol it was running on good ol' 87 octane.

15.611@88.51MPH

Oh yeah I did 13.996@98mph on 87 octane LOL

I did 13.996 about 3/4 of the way down the strip! How come they didn't stop the time there?

[Barry]

How many miles is on the motor with the high KR?

Im thinking were possibly looking at another internal noise that is causing the KR such as a timing chain or rod bearing... Yes its tuned to detect pre-detonation, but nothing is perfect.

If that timing was advanced a few degrees you may see a 15.4.

[woody90gtz]

Barry could be on to something. I know there are certain headers for LS1s that trigger the stock knock sensor, for example. Internal noise would be even more sensitive.