Dealer just put a new engine in 04 Z w/ 55,000miles. Connecting rod bit the dust , so they gave me a new engine. I asked the dealer if the break-in applies since this is a new engine and I was told no. I just feel uncomfortable tearing into a new engine full on without breakin' it in first.
Just wanted to see what some members thought.

 

i would progressivly break it in over 1,000 miles. everyone is going to say something different, a lot of people don't bother with the break in but it really depends on what kind of car you have. if you have a honda civic there is a lot of give with the seals and you need them to seat right, so you break it in. on the other hand every ferarri barely has any give on the seals, and right out of the production area has race drivers rape the cars around a track in the back of the factory before they are even worthy of the ferrari badge. your answer is no you don't NEED to break it in, but i would.

 

Yeah....I'm gonna take it easy for a few hundred miles or so. Thanks for the info.

 

break in on a NEW car from the factory applies to the engine, drivetrain, etc... so they error on the side of caution and give an elaborate ultra conservative break in recommendation...

on a new engine at this stage in the game, the drivetrain and other components are well broken in, the engine should go through a break in period.
the biggest factor for break in is the rings, then the bearings...
best gameplan: run standard motor oil (non synthetic) at least for the first thousand miles. The first couple hundred miles, allow the engine to break for several drive cycles...meaning, get on side road or slow paced freeway, get up to speed, and then from six gear, put it into 5th gear, then 4th, 3rd, slowly, easily... allow the engine to slow down the car... this load type braking will help to seat the rings...

in all honesty, you CAN do this for several hundred miles, I would go on a series of half hour drive sessions, engine brake, keep the rpms under 4500 or so... and then gradually step up the rpms as you gain more miles on the engine..

The above is a CONSERVATIVE break in, I have also, personally broken in a built motor with 50 miles of driving and then thrown it straight on the dyno for 16psi pulls!

good luck,
TODD

 

I'd break it in personally....

 

I'd wait at least a few hundred miles before really getting on it.

 

Yes.........break in the engine and do it with regular oil, NOT SYNTHETIC. I think breaking it in using pregressive higher rpms for 2,000 miles will give you a longer lasting, non-oil burning engine. Start out by not going over 3,500 then work up by 500 rpm increments for at least 200 street or road miles and dont stress it at red line no matter what you do.

These guys that buy the new 350Z and immediately put in synthetic oil are just asking for an oil burner. Its amazing that more dealers dont throw the whiners out when they come in with a mistreated motor. Rings need to seat with the block.