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Skylarking

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To answer my question, where would you suggest the point of going from 5th to 6th at 60kmph would be the most efficient given a bog stock 317kw LS3? Also question 1 and 2, thoughts?
Do you have an auto with paddle shifters?

If so get an BT OBD dongle and an app for your phone and you should be able to log gear position, throttle, rpm and instant fuel consumption. Then go for a drive and when the car is in 5th, at different revs, manually change to 6th. By logging such you’ll work out what the sweet spot is w.r.t fuel consumption and rpm for 5th to 6th gear change.. you can repeat the same for all gears and you’ll have answered your own question and learnt a thing about your car...

If it’s a manual, not sure whether there is any gear position detection sent to ecu or such... but there man be some ways around that...
 

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To answer my question, where would you suggest the point of going from 5th to 6th at 60kmph would be the most efficient given a bog stock 317kw LS3? Also question 1 and 2, thoughts?
not sure what your gearing is like but my E1 has the short 1-5 and 6th drops off so i usually kept it in 4-5th at 60kph or sometimes if it was a long 60kph zone id go into 6th, i usually just go thru the gears u should be able to feel where it likes to work in
 

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Interesting..., so it’s the cluster that caps the display of instant fuel consumption to 39.9?

Any way to remove this silly 39.9 ltr/100km cap as I want to see what’s actually being used.
no that is a cluster readout thing unfortunately, it prob still calculates using higher values but just shows that limit must have been some reason for it, unless someone like envyous customs can hack it
 

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I've seen instant fuel readings on our VX in the 70's and 80's but those numbers are transient and really not relevant as they occur when you give large throttle adjustments when moving off from a stop so you get lots of fuel going in but almost no road speed.

TBH, looking at the instant fuel numbers whilst increasing or decreasing road speed and making throttle adjustments is almost meaningless as the numbers are transient, momentary numbers and really not relevant to overall fuel usage/economy.

If you want to see zero in the panel when decelerating, drop the gears down quicker to keep the engine revs up but under a certain road speed it won't go into fuel cut (I'm not familiar with the numbers for the LS family as I don't have HPtuners) so in that case maybe just clutch in and let the motor idle and just use the brakes (where is the fun in that though?, right?).
 

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also if ur on factory tune then your PE is rich prob in the 10-11's:1 AFR so with a tune u can lean that off to mid/high 12's and use less fuel but make more power
 

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no that is a cluster readout thing unfortunately, it prob still calculates using higher values but just shows that limit must have been some reason for it, unless someone like envyous customs can hack it
I suspect the ECU must still controls fuelling which must be accurate at all engine speeds and the reason it’s capped is probably political as GM/Holden must be embarrassed at mid throttle fuel consumption when taking off at lights.

Heck my old Ford 6 cylinder would get 99 ltrs/100kms (capped to this max due to 2 digit display hardware) but still, was easier to learn where to ease off the throttle as you could see the consumption... and it did make a difference to overall consumption as you learnt where the throttle pedal started to such :p In contrast with the LS3, it’s hard to learn where the throttle sucks as it almost always sits above 39.9 as at 28 you’re almost off the throttle pedal and small cars blast past you at the lights :rolleyes:

Maybe once warranty is done, a new diff ration and an tune (with some other bits thrown in) will change her character and improved efficiency :p
 

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I've seen instant fuel readings on our VX in the 70's and 80's but those numbers are transient and really not relevant as they occur when you give large throttle adjustments when moving off from a stop so you get lots of fuel going in but almost no road speed.

TBH, looking at the instant fuel numbers whilst increasing or decreasing road speed and making throttle adjustments is almost meaningless as the numbers are transient, momentary numbers and really not relevant to overall fuel usage/economy.

If you want to see zero in the panel when decelerating, drop the gears down quicker to keep the engine revs up but under a certain road speed it won't go into fuel cut (I'm not familiar with the numbers for the LS family as I don't have HPtuners) so in that case maybe just clutch in and let the motor idle and just use the brakes (where is the fun in that though?, right?).
I thought control of transient conditions was critical in good engine management, fuel consumption and pollution control... but I don’t know about HPtune and haven’t dabbled with altering a tune...

What I don’t know is if I use medium throttle when taking off at lights, a transient condition to get to 60kph, it has huge impact on overall fuel consumption :p
 

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I suspect the ECU must still controls fuelling which must be accurate at all engine speeds and the reason it’s capped is probably political as GM/Holden must be embarrassed at mid throttle fuel consumption when taking off at lights.

Heck my old Ford 6 cylinder would get 99 ltrs/100kms (capped to this max due to 2 digit display hardware) but still, was easier to learn where to ease off the throttle as you could see the consumption... and it did make a difference to overall consumption as you learnt where the throttle pedal started to such :p In contrast with the LS3, it’s hard to learn where the throttle sucks as it almost always sits above 39.9 as at 28 you’re almost off the throttle pedal and small cars blast past you at the lights :rolleyes:

Maybe once warranty is done, a new diff ration and an tune (with some other bits thrown in) will change her character and improved efficiency :p
yea the only thing i use the instant usage for is to keep track of how it sits at cruise thats all, it stays pretty consistent so if u see it change like i did once i then found an issue with a failing 02 sensor so replaced and readout was back to normal, transient fueling can be adjusted but same as pump shot on carby its needed for most throttle changes, then u have evaporation and impact factor to compensate for but that might be going too far :rolleyes:
 

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I thought control of transient conditions was critical in good engine management, fuel consumption and pollution control... but I don’t know about HPtune and haven’t dabbled with altering a tune...

What I don’t know is if I use medium throttle when taking off at lights, a transient condition to get to 60kph, it has huge impact on overall fuel consumption :p

Well yes the control of transient conditions is critical to engine function but the instant fuel readout numbers for the numpty behind the steering wheel means fairly much nothing.

I did a gear ratio change in the diff on the Super6 during covid, I am still playing with the tune 6 months later trying to optimize ****. I don't have a dyno so I can't do steady state load tuning for peak torque at different rpm/load points so I'm doing it all by street driving.
 

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I did a gear ratio change in the diff on the Super6 during covid, I am still playing with the tune 6 months later trying to optimize ****. I don't have a dyno so I can't do steady state load tuning for peak torque at different rpm/load points so I'm doing it all by street driving.
SD tuning on the street... fun if u only have flat ground, if u can use math/pids with your scanning u can use vehicle speed against previous vehicle speed in time to get a number for acceleration so if u can use repeatable situations and the number goes up ur increasing torque/power, also good for long power pulls so u can see where the engines power range is
 
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