L30 / L31 "base engine friction torque vs rpm vs vacuum" table

[1project2many]

Some of the even more complex modeling of the LSx engines is not enabled on the L31 van, such as A/C Torque vs A/C pressure.

I suspect that may be due to the number of non-GM companies involved in building and selling van chassis vehicles. I've got A/C systems here from four different companies and there are multiple variations even then. Some of our cutaway chassis run three condenser fans drawing 30-40A, with front and rear blowers adding another 15A or so through hybrid evaporators with orifice tube front and TSV rear units.

What I find interesting is how Ford has handled some of it. Upfitters (body builders) are advised to obtain Ford reprogramming equipment and to download various calibrations for modifications such as larger alternator, dual alternator conversion, dual a/c systems, and possibly others. Much better IMO.

Hmmm... I'd like to meet the guy who's job was to motor an L31 to 8000 rpm to measure friction torque. ;)

If we ever get unburied from snow (we're only 8" from a record February, and they're predicting 6"-12" today and tonight) I'll check out some of my van cals just to see if there are any variations.

The ultimate goal here was to try and develop a model for the 3" stroke engine in my Suburban. It seemed so simple in the beginning...

[Fast355]

I suspect that may be due to the number of non-GM companies involved in building and selling van chassis vehicles. I've got A/C systems here from four different companies and there are multiple variations even then. Some of our cutaway chassis run three condenser fans drawing 30-40A, with front and rear blowers adding another 15A or so through hybrid evaporators with orifice tube front and TSV rear units.

What I find interesting is how Ford has handled some of it. Upfitters (body builders) are advised to obtain Ford reprogramming equipment and to download various calibrations for modifications such as larger alternator, dual alternator conversion, dual a/c systems, and possibly others. Much better IMO.

Hmmm... I'd like to meet the guy who's job was to motor an L31 to 8000 rpm to measure friction torque. ;)

If we ever get unburied from snow (we're only 8" from a record February, and they're predicting 6"-12" today and tonight) I'll check out some of my van cals just to see if there are any variations.

The ultimate goal here was to try and develop a model for the 3" stroke engine in my Suburban. It seemed so simple in the beginning...

On the same token, I would like to tweak my tables for the LT4 cam....I wonder how much a cam changes that model.....

[1project2many]

Hmmm..... Good question. Typically I'd expect it see an inverted version of the torque curve in the tables but with the highs and lows where they are in this table I really don't know what's going on.

[EagleMark]

I think his picture is HP Tuners and I don't know what they use? The numbers from TunerCat look to be percent?. In EFI Live most of this is done in Eq Ratio or Grams*Kelvin/kPa and really confuses you.

I have no idea, have not worked on this? Just looked an EFI Live has nothing, well it's as worthless as tits on a bull for vortec anyway...

[Hog]

Hmmm... I'd like to meet the guy who's job was to motor an L31 to 8000 rpm to measure friction torque. ;)


The ultimate goal here was to try and develop a model for the 3" stroke engine in my Suburban. It seemed so simple in the beginning...

Well we know they didnt use a "blackbox" PCM to rev that high with the L31.

3" stroke ehh, to bad we couldnt get the data for a 94-96 L99 4.3 GEN 2 engine as it uses the 3" stroke crank.

peace
Hog

[Fast355]

Well we know they didnt use a "blackbox" PCM to rev that high with the L31.

3" stroke ehh, to bad we couldnt get the data for a 94-96 L99 4.3 GEN 2 engine as it uses the 3" stroke crank.

peace
Hog

Pauly,

Have a better plan to investigate. Someone find me a HP Tuners .bin file for the same year 4.8 and 5.3 trucks and I will have a peak. Those two engines are identical minus the crankshaft and rods.