I was looking at a log from the truck and was watching the sae engine load and torque output etc etc.
Anyway how does hptuners measure torque inpu and how accurate is it compared to something like a dyno?
Just wondering......

screenshot...

 

Joe by the vehicle speed indicated in the above screen shot it looks like you were driving recklessly. Poor Joe!

 

no, this is a old scan from the track before the trans broke.

 

IDK the answer to your question but it looks like the calculations are used in the operation of the transmission.

 

I know of one instance where an engine that was developed for road racing (C5R type) was dyno'd and when completed they ran a 20 minute log. He was using an OEM scan software and the delivered torque number was VERY close to the dyno torque. That was in a 6 speed but I don't think the auto's should be any different. My stock LQ9 is supposed to deliver 380 lb-ft of torque and I have recorded between 380 and 390 consistently.

 

A similar question was asked on the EFI Live forum, and this is what I remember reading... As long as the vehicle weight is entered correctly in the scanner and the scan is confined to say 3rd gear, flat surface, etc, it should be close... The numbers should be pretty accurate... TQ and HP are basicaly just a math equation that can be broken down to a very simple equation like F = M * A... Since the computer can scan and determine the acceleration, the mass is main part needed. Very similar to a dyno, a dyno generate a load similar to the vehicles weight and scans the acceleration...

 

I see. What about commanded air/fuel?
Don't have a wideband just yet...plan to get one but right now it's a no dice deal....
anyway how much can you trust the commanded air/fuel?
Looking at my scan it should be pig rich for a NA motor...?

 

well your 02's are reading 851 13.4afr lean and 885 12.85 afr

what I have seen is 870 is a 13.0 afr and a 890 is 12.8 afr or close to it

 

How should i go about getting these two even at a 12.8ish afr?

 

Have you tuned your VE table using the fuel trims?