I think Pruven's dyno has more to do with that.

Mark
www.Quantum-Racing.com

 

The one argument I consistently hear about breaking in engines is, "the engineers must know what they're doing." Why would you assume this? Engineers are notorious for getting in ruts of conventional thinking. If everyone has done it like this for x years and it works (to some extent) why change it? My GSXR 1000 is completely stock and dynoed 4.7 hp more and had a much better torque curve w/ 100 percent leak down, while my buddies with a full Yosh exhaust had a leak down of 95-97 across the cyliders. Mine was warmed and ridden hard-not beaten-with deceleration following all acceleration and his was babied. His leak down is past his rings. An engine with less leak down will last longer! Combustion gases going down into the crank erode rings, lands cyliders and dirty the oil. It sounds like we need some good scientific evidence to sette this debate though.

 

One pair of motors like that is not enough to make any assumptions. I think while many engineers do indeed tend to follow convention, I seriously doubt that the engineers working on something that evolves so much to stay at the top of the competition (like GSXR and EVO) would just follow convention if they could alternatively tell you "go rip it up" and it would also last longer or make more power at the same time.
Was your buddies' GSXR tuned while adding the exhaust? Maybe the fueling if off. Maybe it has more mileage. Maybe his oil wasn't changed as much. Maybe someone at the plant messed it up a bit. Maybe, maybe, maybe.
An engine with less leakdown will (all other things the same) make more power. 4.7 hp could (in some cases) be simply the weather, the dyno, the ECU's curve, the fuel, etc.
The only ones who have the scientific evidence ARE the engineers. Why is everyone so quick to distrust them? Many others might simply go off of a two sample example like you mentioned. Suzuki and Mitsubishi blow many motors to pieces to find what works best. They do every little thing to make it last longer, rev harder and higher, etc. Then we question if they know how to break it in?


Mark
www.Quantum-Racing.com

 

The engineers that build these car really have NO precise idea how the engines break in or wear over the course of the vehicle. The only thing they have to go by is data collected by race teams (not exactly true to life) and the dealer network (and generally speaking we all know how well educated and trained the dealer network is).

I agree with you, two motors are not a large enough sample to draw any conclusions. It is merely anecdotal evidence. I have a feeling the "Motoman" technique is as well. Until there is some way to collect precise data regarding the operation of the motor through out it's life we'll never know for sure what the best break-in technique is. There are too many variables at play.

Also, let's face it, 5K RPMs of engine speed at 10% load does not generate the same amount of cylinder pressure as 100% load at full boost at the same RPM. The inertial forces acting on the valve train and crankshaft components may be similar under both conditions but that has little to do with seating the rings. Cylinder pressure helps seat rings.

 

I don't. If other cars dynoed stock at 220 on the same dyno, same day, and I dynoed at 234, it seems logical that my break-in could have resulted in me having more power then other stock evos.

 

Dont worry about taking the girl up in revs, lets say 2nd to 3rd gear shift, just dont hang out there or try & find the limiter!

Just be smart about it. As long as the oil is up to temp, you should be fine!

After break-in, we run our engines through various "cycles" to simulate WOT applications before we even run our power checks & send them to the track.

 

Yes I agree with you there, but many other dynos seem to spit out slightly lower numbers. Some quite a bit lower.

Mark
www.Quantum-Racing.com

 

Ok, I need more advice. I am looking at a 2003 Evo with now about 8000 miles on it. I'm very close to pulling the trigger on this car but I want to make sure that I'm not walking into something I shouldn't be.

My concern was today I asked the owner how he broke it in. He replied that he bought the car with 50 or so miles on it out of Georgia. Before the car was shipped up the dealer did an oil change and sent it on it's way. He then said that he drove the car to about 2800 miles before having the next oil change performed. From here on out it's been every 3000.

So now here's the big question. By not doing the oil change at 1000 miles, do you think that the valves and such may not have seated well or that there may be any other longevity issues I may have to deal with since this was not done?

I'm hoping to hear from those that have some experience with breaking in engines like this.
Thanks in advance.

 

I was at first concerned with this but when I looked at how many beater dsm's are still on the raod afyer 10 years I quickly stopped worrying.

By the way some one is going to tell you to searc, and you just opened a can of worms because there are many different opinons about break-in.

 

You have to break these cars in?

 

The question is more debated on whether the you break the car hard or easily. Considering the manual doesn't recommend changing the oil til at least 3750 miles, I wouldn't worry about that. There have been some polls on this board talking about easy vs hard break-in, if you have the smell of gas in the oil or not. Seems the majority of people who broke the car in lightly (thereby not using cylinder pressure to seat the rings), have a gas smell in their oil. If I were to do it again, I would have followed Motoman's hard break-in method.

 

Seriously, if I were buying used EVO I would be more concerned about the owner's personality. Let him or her drive the car with you in it...see how they think, shift, etc. Tell him to get on it when it is cold..see if he will. Tell him to power shift it...see if he will. If he does abuse on your command, he likely did when he owned it. That will tell you worlds about the car's condition.

 

Guys, I think his question was whether such an early oil change would negetively effect break in. The answer is no, as these cars came with mobil 1 synthetic from the factory, with no additives, and they probably filled it with the same. In fact, it's a good idea to swap this out for castrol gtx (or comparable dino oil) when you take delivery. (under 25 miles)

 

 

If you're really that concerned have him dyno the car. That shoud tell you how strong the engine is. Try to get it on a dyno that other evos have used, so you can compare.