SeanE

Hey guys,

I'm replacing my current high mileage motor that has some "problems" with an 01 crate motor I was able to get a great deal on though a buddy of mine who races spec miatas. My question is the break-in procedure. What do you guys recommend on how to go about doing it? When the engine gets put in, I'll be installing all of my turbo stuff beforehand to make the install a lot easier so I know I'll need to stay out of boost until after the break-in. What oils should I be using to do this as well?

Thanks.

neogenesis2004

iTrader: (12)

I'd break it in NA for a few runs down the street first personally. Al I would do is throw the motor in, plug in my stock ecu, make sure fluids are in, and then go beat up the road for a few runs down the street. After that point change the oil and its pretty much broken in.

Savington

iTrader: (31)

Crate motor? I'd break it in by disassembling it completely and cleaning up all the manufacturing defects and **** they leave in those motors. Mazda crate motors are notorious for being pretty bad inside.

J.T.

Lol. There a lot of opinions on this ****, a friend of mine builds a lot of motors and hesaid drive it fairly hard, and if your worried about it do a few hard runs to 60 and engine brake down to 10 or 15 and do that like 10 times, drive it a while, then change the oil.

sn95

iTrader: (2)

Traditional break-in procedures are to avoid heavy loads at low speed ("lugging") , constant speeds and excessive RPM for the first 1,000 miles. I'd drive it 1,000 miles making sure to vary the speeds (don't drive 1,000 miles cross country at a constant 70mph) and trying to keep below redline. After that, I'd change the oil and filter (cut the filter open to look for debris if you're ----), run a compression check and/or leakdown test and then go for the turbo install. Troubleshooting turbo install problems may be easier if you know you are starting with an engine that has good compression and no oil or coolant leaks.

Up to you if you want to go the "traditional route" and do the first 1,000 miles on dino oil before you switch to synthetic at the first oil change. A lot of people feel that starting a new motor on synthetic increases the time it takes to seat rings; almost all new OEM turbocharged cars come with synthetic from the factory. YMMV.

neogenesis2004

iTrader: (12)

IMO if you think it takes a motor longer than a few minutes to break in on a high rpm, high load run, then you are an idiot. Using the stock ecu to do so is perfect in his case because it will already be tuned.

Do you think top fuel motors, or any race motor for that matter goes through a 1000mile break in before they put it on the track? No, they engine dyno tune it and then throw it in a car to beat it up. As far as the motor is concerned it doesn't care if its a race car of a street car. Its the same components, same machining processes.

The traditional break in was performed for previous decades before we had the amazing precision and accuracy we now have with current machining tools. It is no longer required.

J.T.

http://www.mototuneusa.com/break_in_secrets.htm
http://motorcycles.suite101.com/arti...in_controversy

Ive seen that first article linked in several places, seems to be the general consensus

JDMAflac

iTrader: (1)

Very good read, i'll keep this in mind when breaking in my motor.

SeanE

Thanks for the link J.T. I'll have to print that out and keep on hand with me. I'll hold off on re-installing the the turbo stuff for now it looks like so I can run NA for a while. I like the dyno idea the best since trafffic sucks around here and it'd be tough to do a good break-in on the street. I'm wondering before the install if I could find someone with an engine dyno to perform the break in.
Savington, I hadn't heard the reputation about Mazda crate engines so now that gives me something else to think about.

sn95

iTrader: (2)

I gave him an economical street "break-in" alternative. I'm not disputing the fact that a good dyno operator (Westech etc) with a load dyno can break-in an engine in under an hour...not everyone has access to a a load dyno (most common chassis dyno is a DynoJet, which is NOT a load dyno).

BTW, it is a meaningless to compare breaking in a 7,500 horsepower Top Fuel motor (Duh, filled water jackets & no cooling system to speak of) to a crate Miata street engine, especially since the Top Fuel motor is already broken-in on the engine dyno! Good engine dyno operators break-in street engines by running the engine at varying RPM and loads, then start the the full power runs. It's a great way to break-in an engine, but I think the price of setup, fully instrumented break-in (4 cylinder EGT, oil temp & pressure, wideband O2, RPM, MAP etc) on a SuperFlow 9000 might be a little rich for Miata crate motor.

neogenesis2004

iTrader: (12)

My point is that he already has the stock ecu which is tuned for his stock crate motor so he can forgo the engine dyno. Please extract your head from your ***.

sn95

iTrader: (2)

????????

sn95

iTrader: (2)

Ummm, I'm not the one with his head up his ***!

1. Dyno break-in (chassis or engine) consists of more than 1 or 2 pull power pulls
2. The "modern instrumentation" you refer to that helps monitor proper break-in is usually limited to engine dynos (unless the OP has 4 cylinder egt, 4 cylinder CHT, TIT, and a calibrated electronic MAP sensor already in his Miata)
3. Street engines and race engines rarely use the same internal parts
Cast pistons vs. forged 4032 or forged 2618
Stock rods vs. H beam forged or I beam billet
Hollow stock cams vs. billet aggressive lift/duration/ramps
Steel valve spring retainers vs. titanium
Stock valve keepers vs. hardened steel valve keepers
Stock valves vs. SS oversized valves
Etc. etc, etc
4.While the machining operations are the "same" between a street and a race engine, the tolerances are generally much different
Stock engines run tighter piston clearances, race engines run looser due to different expansion qualities of forged pistons (racers don't care about piston slap)
Top ring gaps are tighter on stockers, looser on race engine (much looser on boosted and nitrous motors to prevent end butting under load)
Rod & main bearing clearances are tighter on stock motors, looser on race motors (racer's don't care about getting 100K on bearings)
etc.

Braineack

iTrader: (62)

If the motor has idled its pretty much "broken in." You just need bunch of heavy pulls of vacuum to help seat the rings...

bryantaylor

iTrader: (5)

MAKE SURE ITS COMPLETLY WARMED UP, WATER AND OIL. then beat the **** out of it. when i got my brand new gixxer, the first thing i did was a 100mph pull up the on ramp outside of the dealership. just don't stay at a steedy load, like cruiseing. vary the RPM's and load

Saml01

iTrader: (9)

Drive it like you stole it.

Mach929

iTrader: (3)

i'm not sure if any of you have ever worked in a new car dealership before. but when the cars are pulled of the trucks and the keys handed over to lot attendants, car washers, techs, the cars have zero miles and cold get the ******* beat out of them.(ask me how i know) then i've seen these same cars come back years later with zero issues, running perfectly. oil never changed after "break in" and changed every 10-13K for their life. oh and they come with synthetic oil straight from the factory

bryantaylor

iTrader: (5)

+1. those techs love doing PDI's