[Ryephile]

Originally Posted by DaveC113

That's the best thing you've posted so far.

However, it doesn't mean that it's impossible to lug the motor. How about when it's fully loaded going up a hill in 6th gear? I would think there's plenty of potential to lug in those circumstances. There are limits to what the ECU knows and can account for.

Check out the other bullet points from post #108. Then consider they work together to form a multi-dimensional strategy. Of course there are limits. Those limits are beyond this threads' topic however. That's a major point.

How does "fully loaded going up a hill in 6th gear" differ from WOT in 1st gear in terms of observed engine load? Of course it's a rhetorical question; it doesn't. You still need to mentally separate vehicle acceleration rate from engine load.

[b4z]

if you have done a lot of lugging on the engine like i used to do with my '87 IROC the crank can eat into the rear main seal. lots of pressure on the crank.

[eimarshall]

Instead of personally attacking each other, why don’t we come back to the question at hand.

It seems we need to break it into 2 questions-
What is lugging?
And
What harm does it do?

What is lugging? I thought lugging was what happened when you had the car in gear and slow down to below idle rpm. It sounds the other ideas posted here focus on load, rpms and duration. I know GM has left this vague in the manual, but it’s not an uncommon term. It sounds like we are all close to the same definition

What harm does this do?
I’m no engineer but I would imagine something similar happens in all those scenarios. Higher cylinder pressures, greater heat build up, potential for pre-ignition. I saw a decent video by the engineering explained guy about why it’s bad but he doesn’t go into the actual math. Can someone speak more to these conditions?


Now I would imagine the tune tries to prevent too much of this with throttle position mapping, pulling timing, etc. but nothing is completely bulletproof. Plus when we modify our cars we introduce unknowns into the equation.

I like the discussion but avoid the petty bickering and maybe we can all learn something.

[Boost Creep]

Originally Posted by eimarshall

Instead of personally attacking each other, why don’t we come back to the question at hand.

It seems we need to break it into 2 questions-
What is lugging?
And
What harm does it do?

What is lugging? I thought lugging was what happened when you had the car in gear and slow down to below idle rpm. It sounds the other ideas posted here focus on load, rpms and duration. I know GM has left this vague in the manual, but it’s not an uncommon term. It sounds like we are all close to the same definition

What harm does this do?
I’m no engineer but I would imagine something similar happens in all those scenarios. Higher cylinder pressures, greater heat build up, potential for pre-ignition. I saw a decent video by the engineering explained guy about why it’s bad but he doesn’t go into the actual math. Can someone speak more to these conditions?


Now I would imagine the tune tries to prevent too much of this with throttle position mapping, pulling timing, etc. but nothing is completely bulletproof. Plus when we modify our cars we introduce unknowns into the equation.

I like the discussion but avoid the petty bickering and maybe we can all learn something.

Good point I wanted to bring up earlier.
When a larger aftermarket camshaft with extra duration is installed, the point where the lugging sensation occurs increases as the power band has moved up higher in the rpm range.
Where a stock cam can produce low rpm usable power to move the vehicle effectively, a larger cam will struggle with low rpm torque production making idle speed parking lot maneuvers a little more interesting.