ZO6 HP increase
Thread Starter
6th Gear
Joined: Aug 2024
Posts: 6
Likes: 1
ZO6 HP increase
This sounds strange to me and never heard of this nor did I find any reference on the web, but just got new 2025 ZO6 after I traded in my 2024 Z51. Service Manager at dealership told me the ZO6 only is programmed to use 65% of its HP till it hits 5,000 miles then full HP and that in track mode the HP increases to 740 since the vehicle is tuned differently in that mode. Has anyone heard of this before and I would think GM would share this but I never heard of this? Don't shoot me, I heard it from someone that handles Corvettes at the dealership
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May 29, 2025, 12:51 PM
Drifting
Joined: Oct 2018
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From: C&D 10 Best loop
I suggest you never use that service department again.
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From: DFW Area TX
The C8 does limit torque in 1st and 2nd gear for the first 500 miles. From Tadge:
OP, please name the dealer so that other members can avoid these clueless idiots.
This is a good opportunity to clear a few things up. For as long as I can remember we have recommended a 500 mile break in period for new cars. Not just Corvette, all cars. It has been emphasized in the owner’s materials with further definition around brakes and driveline.
Why is this important? Any machinery that has moving parts, whether they have point contact, a rotational interface or slide against each other will “bed-in” over time. What that means is, no matter the manufacturing process, two interfacing parts will find their own equilibrium. You can think of it as mutually refining each other’s surface texture until they reach a steady state. This steady state condition generally minimizes noise, vibration and wear. Although manufacturing has improved to a point where break in effects are minimized, they are still at play despite claims to the contrary. And the truth is, there may be additional minor benefits to a longer break in period. If it was my car, I would try to be patient for 1,000 miles.
Starting with the 7th generation Corvette we established a variable red line on the tach to give drivers a visual indication on when it would be advisable to take it easy on the car. We used it for the first 500 miles of driving and when the engine was coming up to operating temperature after break in was complete. Our reconfigurable display enabled us to to that. We didn’t actually limit torque, horse power or RPM, it was just a visual indication. Despite the tach and owner’s instructions, some customers use the full capability of the car immediately. We have too many videos of people doing burn-outs off the dealer lot or showing up to a track (both road course and drag strip) with near zero miles. Taking any green and cold engine to max torque and speed can cause undesirable wear patterns that could affect engine operation over the long term. Running full torque through the trans under the same conditions can score gears, especially those in the differential after the engine torque has been multiplied. We have had examples of customers not observing the break in guidelines and then returning the car to the dealer with complaints of gear noise or differential whine.
For the 8th generation Corvette, we have taken it a step farther. With more weight on the rear, the car has more traction and we take advantage of that with more aggressive gearing. That translates into more torque multiplication and more loads in the driveline. We decided for the first 500 miles to limit maximum torque in first and second gears. The torque reduction is roughly 25 to 30% depending on which transaxle (standard or Z51) and which gear. That may sound like a big reduction, but in reality the car is still really fast. In fact, you could easily spin the tires on some surfaces. Engine speed is not limited at all – it will wind out to redline. So the torque reduction limits the worse of potential break in wear, but is not a panacea. We will still be asking customers to stay well off max torque and speed for the first 500 miles. We know it is hard to stay patient when such performance is available, but it will pay off in the long run.
Why is this important? Any machinery that has moving parts, whether they have point contact, a rotational interface or slide against each other will “bed-in” over time. What that means is, no matter the manufacturing process, two interfacing parts will find their own equilibrium. You can think of it as mutually refining each other’s surface texture until they reach a steady state. This steady state condition generally minimizes noise, vibration and wear. Although manufacturing has improved to a point where break in effects are minimized, they are still at play despite claims to the contrary. And the truth is, there may be additional minor benefits to a longer break in period. If it was my car, I would try to be patient for 1,000 miles.
Starting with the 7th generation Corvette we established a variable red line on the tach to give drivers a visual indication on when it would be advisable to take it easy on the car. We used it for the first 500 miles of driving and when the engine was coming up to operating temperature after break in was complete. Our reconfigurable display enabled us to to that. We didn’t actually limit torque, horse power or RPM, it was just a visual indication. Despite the tach and owner’s instructions, some customers use the full capability of the car immediately. We have too many videos of people doing burn-outs off the dealer lot or showing up to a track (both road course and drag strip) with near zero miles. Taking any green and cold engine to max torque and speed can cause undesirable wear patterns that could affect engine operation over the long term. Running full torque through the trans under the same conditions can score gears, especially those in the differential after the engine torque has been multiplied. We have had examples of customers not observing the break in guidelines and then returning the car to the dealer with complaints of gear noise or differential whine.
For the 8th generation Corvette, we have taken it a step farther. With more weight on the rear, the car has more traction and we take advantage of that with more aggressive gearing. That translates into more torque multiplication and more loads in the driveline. We decided for the first 500 miles to limit maximum torque in first and second gears. The torque reduction is roughly 25 to 30% depending on which transaxle (standard or Z51) and which gear. That may sound like a big reduction, but in reality the car is still really fast. In fact, you could easily spin the tires on some surfaces. Engine speed is not limited at all – it will wind out to redline. So the torque reduction limits the worse of potential break in wear, but is not a panacea. We will still be asking customers to stay well off max torque and speed for the first 500 miles. We know it is hard to stay patient when such performance is available, but it will pay off in the long run.
Thread Starter
6th Gear
Joined: Aug 2024
Posts: 6
Likes: 1
To Tadge
Sounds like the service manager heard enough to be dangerous, what was stated here about limiting torque could have been misinterpreted by him. More importantly it’s opened up a discussion on issues(potential) with the C8 during a period of time if the vehicle is driven at max causing significant damage and during a warranty period. The C8 is a finely tuned engine/transmission with a little bit of aggressive driving early on that can result in costly replacements. What about the HP increase in track mode where he stated the tuning changes, anything to that? Thanks
Last edited by Luckydog!!!; May 29, 2025 at 02:10 PM.
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The dealer told you a big whopper
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Paragon used two Dynos for the E-Ray tied together with a belt. As they said the software requires feedback from both front and rear to get max power readings. Tough to beat 100% torque at 0 rpm with an electric motor AND traction from FWD. Why on street pavement the E-Ray is ahead of Z06 about a car length after about 1 second after Launch!
Last edited by JerryU; May 30, 2025 at 09:20 AM.
