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Break-in period

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There seems to be a lot of controversy over how to properly break-in a car. Do you folks at Shelby have any break-in suggestions for new GT500 that will be converted to the Super Snake package?


...I know drive it like I stole it







Another member on SU (SuperSnake08) had a very good write up on the break in procedure.

Here it is:


My personal experience having built a few motors over the years is this. The rings have a fairly short opportunity to take full advantage of the crosscut hone pattern most motors have. That mildy rough surface helps the process by creating a good "seal" around the rings avoiding some of the carbon build up that results on the piston lands and valves on motors that do not seal quite as well. In a high boost application the boost pressure forces the rings to expand against the cylinder walls and its hone pattern.If you do not do this early in the game the hone will wear down and you may never get the tight seal a good break in creates. That being said get the motor up to operating temperature before laying into it too heavy, avoid extended periods of sustained idle or steady rpms and put some boost pressure on the motor to force those rings to expand. You do not need to do a holeshot to accomplish this. In fact I would avoid the high impact that creates and focus on the motor. Vary rpm, build some boost early, change speeds and be sure to go through enough heat cycles to complete the breakin. I have run some motors on the dyno day 1 and with others did a more progressive break in.

A very cautious alternative for the more faint of heart would be for the owner who just can't allow him or herself to drop the hammer to the max to try this type of a gradual, yet proactive break in:

First 100 mi -vary speeds and rpm with max rpm 3000

next 100 mi- vary speeds and rpm with max rpm 3500

next 100 mi- vary speeds and rpm with max rpm 4000

next 100 mi- vary speeds and rpm with max rpm 4500

next 100 mi- vary speeds and rpm with max rpm 5500

Let her rip!!


I personally do not think you need to be this conservative, as long as you are at operating temperature and not missing gears at 6000+ rpm which would not be good for a new motor(nor would radical downshifts-eg 4th to 2nd at 110mph which can bend valves and impact the valvetrain.

As far as owner manual recommendations regarding top speeds of 55mph until 500 or 1000mi- forget it. That is nonsense and will leave you with one slow motor that likely will consume more oil than one broken in more aggressively. Good luck to all those about to put these delicious mod motors to the test.

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