ZL1 1LE Track Prep Guide: Adjustment Suggestions
 

Have you guys seen this document? It's the second-to-last page of the 2018 track prep guide.

Pretty neat stuff!

Attachment 920015

I honestly don't recall that page. I'm going to check when I get home to see if it's been added. Thanks!

That still has great info for us non ZL1 1LE guys. The 32-35 hot target range sounds about right with my experience on the SS 1LE. Interesting that they say to target 37 hot in the SS 1LE performance supplement.

Here's the entire track prep guide for 2018...information for V6 1LE, SS, SS 1LE, ZL1, and ZL1 1LE:

Thanks for posting the whole updated guide.

I'd love to get an official clarification on this hugely ambiguous phrase.

By definition, the engine's job is to do work, which = labor

High throttle application in wrong gears. Like WOT in 4th gear at 30mph

That would be 1425 RPM, well within the engine's operational envelope per the published SAE chart. Incidentally it would be roughly 1100 Lbf to the contact patch. How do you think the calibrators tune those load points?

I know you're trying to be helpful, but the official verbiage is garbage at best.

If their intent is to imply "don't instigate LSPI", then why even have DBW or a knock feedback loop? Obviously we won't ever get an official answer, because then GM would be tied to an official position. For the rest of us calibrators out there, it's just a legal easy-button for GM to push just in case their guys failed to get the LSPI tuning right.

yep, seen it and posted it before

Indeed you have!

http://www.camaro6.com/forums/showth...4#post10024414

I don't see engine load on the chart? Heavy Throttle in High gears at low RPMs is not ok for any engine. Aka lugging. You are putting the engine at a disadvantage https://youtu.be/soJea7xEt-8

Best definition I've found for lugging, at any combination of load and RPM that results in "unsmooth" acceleration. Sure you can go full load and lowish RPM and have smooth acceleration albeit slowly but thats just extra load on the engine for no reason. If you had an automatic it's literally programmed not to do this.

What load to you think it being presenting in an "SAE certified power" chart? This is rhetorical. It's WOT. Even if that's not explicitly stated in that chart circulating the internet. What the chart shows is SAE has certified the LT1 will make *that* power and torque from 1000 to 6000 RPM, and it's provable by taking your engine and putting in a dyno cell and running it across the same RPM band. It demonstrates that running WOT at 1000 RPM is not damaging, in fact it has a guaranteed output.


What you're saying is you haven't found an actual technical answer on what "lugging" is. Automatic trans are literally programmed to give you peak acceleration at max requested load, regardless of the engines' breadth of capability. Bringing the automatic transmission strawman into the argument doesn't define the term "lugging". If we went further with the strawman, I'll bring up CVT's operating the engine solely at peak BMEP and peak BSFC RPMs. That doesn't help either to define "lugging", because in both instances we're only talking about getting peak performance out of the system, not defining a term on the outskirts of the operational window.

Is "lugging" defined as "WOT at idle"? Show some proof. In practice, even if you floored it at idle, going from 650 RPM to 1000 RPM takes about the time it takes you to get your foot to the floor. If we take one of the magazine tests, a timed 5-60 MPH, that means you'd have to be rolling in 1st at 632 RPM and then go WOT. Are the car magazines knowingly "lugging" the engine, or are they still within a reasonable operational window? Again, show proof either way.


"Lugging" is a leftover term for engines prior to the LSPI-controlled era, and is woefully confused with actual knock and LPSI events. As such, with certain engines in certain conditions, you could be "lugging" at 4k at part throttle. Others are perfectly operational at 400 RPM at WOT. Even then, this archaic term only applies to old engines without closed-loop knock and LSPI control. As such, I go back to my earlier point. GM left such a term in their manual as a legal "escape clause" to keep lazy calibrators from being a financial drain on the company with bad tuning.

Or...they left the language in there because it's colloquial and "LSPI" sounds like a disease on an infomercial to most people reading that manual (if they read it). As far as the intent...I would imagine the directions are in there to prevent those situations from occurring in the first place, thereby preventing the calibrations (which I'm sure are fine) from ever being needed.

You don't apply WOT in 6th going 45 down the road...because it's a useless endeavor, if you want to accelerate, change down...the manual is just reinforcing that thought.

The above graph is a representation of engine power on an engine Dyno with a 1:1 ratio, alternator loads, cooling fans loads..etc but not the load of the vehicle.

What is the engines Ratio to the wheels in each gear? For example let's say you are at 800rpm in first vs 6th. What's the mechanical advantage in each gear? 1st being >1 and 6th being <1.

Going WOT in 6th at 800RPM results in Lugging. Give it a try for your self.

Also automatic transmission comment was more to show that they down shift to prevent high engine loads at given throttle position. For example you are towing something heavy and experience a small hill, and you apply more throttle slowly to keep the same speed. The transmission wil eventually downshifting to prevent prolong periods of high engine loads because lower gears have greater mechanical advantage.

You're asserting that 800 RPM, in 6th gear, is "lugging". Ok, what does that mean, technically?

*Are you dissatisfied with the NVH being transmitted into the body?
*Are you operating the engine at an RPM where there is inadequate oil pressure, losing hydrodynamic bearing properties and causing metal/metal contact?
*Is the ECU unable to control knock at 800 RPM?
*Are you dissatisfied with the amount of acceleration?
*How does what the engine is connected to have any impact on its ability to operate? Why 6th gear, why not held at a static RPM on an engine dyno, like engine dyno's can?

You haven't explained what "lugging" actually *is*, yet here you are asserting a scenario where "it" is happening. If you can address any of those bullet points, we'll be heading in the right direction.