Flat-Plane Crank Motor (LT6 Motor/Z06 Corvette) Break-in Methods/Tips?

[ArmchairArchitec]

Hi all, picking up my Corvette Z06 (with the 5.5L LT6 flat-plane crank DOHC motor) in a couple weeks and have a long trip home from the dealership (~6 hours) which is mostly highway driving.

My question is, regarding "varying the engine RPM", when on a highway, how often should I be doing this (every few minutes, seconds, etc.), and should I do it by changing cruising speeds within the same gear, or by downshifting/upshifting?

It's a dual clutch transmission and I read a random person's tip somewhere that during break-in, try to avoid downshifting to reduce the engine speed, as it puts a lot of stress on the DCT during break in.

Any other methods, tips? Thanks!

 

[DemoFly]

The engine has already been rigorously simtested and EPA tested.

Rings don't need to set, your dual overhead camshafts with mechanical finger followers are pressure lubed. The Tremec DCT has a 500 mile clutch break in period. Like any other clutch. No hard launches or full throttle acceleration.

Change the factory fill early as wear metals are higher on a new engine, and enjoy your car.

 

[Zee09]

Congrats
I would change the oil and filter 7x in the first 1200 miles

 

[oldhp]

Take the back roads home. Enjoy the view. Each time you let it sit, everything heat soaks. Rear gears like the cooling off and then reheated. I only drive back roads the first 500 miles to help everything break-in. I.E. Brakes, transmission, engine.

 

[Wrenchturner44]

If I am not mistaken the ECM is already programmed to limit your engine parameters and probably some shifting inputs to until you hit 500 miles.

 

[ArmchairArchitec]

If I am not mistaken the ECM is already programmed to limit your engine parameters and probably some shifting inputs to until you hit 500 miles.

That's correct, but I'm talking about optimizing the break-in, such as varying the engine RPM.

Not sure if there is extra shifting done by the DCT when in auto mode, during the break-in period.

 

[Dave Hess]

Drive it normal for 700 miles and then enjoy the car.

 

[Cujet]

After doing many hundreds of dyno runs, testing and modifications, the idea that “break in” method makes any difference is in error. Engines that do an initial leak check and adjustment, followed by righteous Dyno testing at all RPM’s and boost levels if turbocharged, ARE exactly the same as any other low time engine, abused or not. The precision of modern engines and machining ensures this.

let’s put this another way. Low time engines have no real wear. High time engines often show significant wear. That significant wear takes 5,000 or 10,000 hours to happen.

Drive it like you want, pass a few people, stop for gas, change the oil frequently.

 

[Kurtatron]

After doing many hundreds of dyno runs, testing and modifications, the idea that “break in” method makes any difference is in error. Engines that do an initial leak check and adjustment, followed by righteous Dyno testing at all RPM’s and boost levels if turbocharged, ARE exactly the same as any other low time engine, abused or not. The precision of modern engines and machining ensures this.

let’s put this another way. Low time engines have no real wear. High time engines often show significant wear. That significant wear takes 5,000 or 10,000 hours to happen.

Drive it like you want, pass a few people, stop for gas, change the oil frequently.

Kinda like boat engines showing hours running instead of an odometer? Have you done any work on boat engines? I’m curious how consistent boat engines wear vs hours ran. Are wear profiles really that consistent?

 

[Cujet]

Kinda like boat engines showing hours running instead of an odometer? Have you done any work on boat engines? I’m curious how consistent boat engines wear vs hours ran. Are wear profiles really that consistent?

Yes, I did some outboard engine testing in years past. Along with plenty of V6 and V8 inboards. Wear rates are often much higher on boats. However engine temps are often not well managed and corrosion is a constant problem. Many Boat owners really don’t maintain their engines well, and let them sit unused forever.

 

[dfarr67]

Either something breaks and you've got warranty- or you're good to go.

 

[Marcozi]

Take the highway, stp ever hour for 15 minutes. Accelerate slowly. Change oil and filter at 1200 miles. Send old oil sample out for UOA.

 

[BMWTurboDzl]

Hi all, picking up my Corvette Z06 (with the 5.5L LT6 flat-plane crank DOHC motor) in a couple weeks and have a long trip home from the dealership (~6 hours) which is mostly highway driving.

My question is, regarding "varying the engine RPM", when on a highway, how often should I be doing this (every few minutes, seconds, etc.), and should I do it by changing cruising speeds within the same gear, or by downshifting/upshifting?

It's a dual clutch transmission and I read a random person's tip somewhere that during break-in, try to avoid downshifting to reduce the engine speed, as it puts a lot of stress on the DCT during break in.

Any other methods, tips? Thanks!


View attachment 178214

Per the OM

"During the first 800 km (500 mi), engine torque will be limited in low gears. For the first 322 km (200 mi):. To break in new tires, drive at moderate speeds and avoid hard cornering.. New brake linings also need a break-in period. Avoid making hard stops. This is recommended every time brake linings are replaced.

For the first 800 km (500 mi):. Avoid full throttle starts and abrupt stops.. Do not exceed 4000 rpm.. Avoid driving at any one constant speed, fast or slow, including the use of cruise control.. Avoid downshifting to brake or slow the vehicle when the engine speed will exceed 4000 rpm.. Do not let the engine labor. Never lug the engine. This rule applies at all times, not just during the break-in period."

For a 6 hour drive I have no idea how I would handle that. My initial thought would be to ship the car home.

 

[Torrid]

What a beautiful car you absolute champion. I'd just not hammer it around too much the first 500 miles and not overthink it. I don't think the car will let you use launch control for the first 500/1000 miles anyway, but I wouldn't attempt to use it before 500 miles anyway. Personally I don't use launch control often with DCTs or launch manual cars hard often. It feels like unnecessary wear and tear. It is fun though and is a must to try for the experience.

 

[We're Metals]

Then its go time...

 

[4WD]

Then its go time...

Good reminder “we be gonna need” to hear mile 501

 

[Cujet]

For a 6 hour drive I have no idea how I would handle that. My initial thought would be to ship the car home.

just drive it. It will be just fine. It is no problem to vary the throttle and speed on the highway.

 

[k1xv]

Sounds like you picked up the car at MacMulkin in Nashua NH and drove it to Philadelphia. There are numerous "blue roads" on the road map to do this trip avoiding Interstates.. Just normal, legal driving on these routes would have been fine. You could have gone from MacMulkin to Route 2 in Massachusetts, taken that to Route 22 south in New York, to Route 44 west, across the Hudson River at Poughkeepsie, then down US 209 to Port Jervis NY, then south along the Delaware River in New Jersey to Trenton.

 

[97prizm]

Hi all, picking up my Corvette Z06 (with the 5.5L LT6 flat-plane crank DOHC motor) in a couple weeks and have a long trip home from the dealership (~6 hours) which is mostly highway driving.

My question is, regarding "varying the engine RPM", when on a highway, how often should I be doing this (every few minutes, seconds, etc.), and should I do it by changing cruising speeds within the same gear, or by downshifting/upshifting?

It's a dual clutch transmission and I read a random person's tip somewhere that during break-in, try to avoid downshifting to reduce the engine speed, as it puts a lot of stress on the DCT during break in.

Any other methods, tips? Thanks!


View attachment 178214

When I went to the Corvette factory tour and museum years ago they mentioned that each vehicle gets dybo tested and if it passes a spin around the track 8 miles or so before delivery. I did see a Corvette fail the dyno test in 1994 not sure why.

 

[ArmchairArchitec]

Sounds like you picked up the car at MacMulkin in Nashua NH and drove it to Philadelphia. There are numerous "blue roads" on the road map to do this trip avoiding Interstates.. Just normal, legal driving on these routes would have been fine. You could have gone from MacMulkin to Route 2 in Massachusetts, taken that to Route 22 south in New York, to Route 44 west, across the Hudson River at Poughkeepsie, then down US 209 to Port Jervis NY, then south along the Delaware River in New Jersey to Trenton.

Good tips. I was on a bit of a timetable so did a combination of highway and local roads. When on highway I downshifted a gear every few minutes.