My motor has been destroyed....

[sheffester]

Well, I finally finished my build this summer. First few days driving the car with the new setup went amazing. Car was very fast. I was very impressed with my 20g. So, a few weeks go by, and I notice the performance getting worse and worse. By the time I got it inspected to drive it down to my house, I couldnt even boost. It would fall right on its face. Tested for boost leaks, no leaks. New plugs and wires didn't fix it. Fuel isn't an issue unless my filter is restricting my fuel flow because of my new pump. Checked timing, and I couldn't get base timing below 11 degrees. Drove it home from work that day, and thats when it happened. I'm going along and all of a sudden hear a snap and metal ringing around in the engine. I shut it off immediately. Pulled the valve cover and saw my rocker sitting in the head, and my lifter snapped. I pulled the head that night and found a snapped valve and a hole in my piston. Long story short, it destroyed my head to the point where I couldn't even remove the spark plug from that cylinder and I need a new bottom end now. The motor only had 500 miles on it. I'm lost as to what could have caused this. Regardless, I'm building a new engine. Am looking for suggestions on what to build, and how extreme to go with a 4k dollar budget. Just looking to bounce some ideas.

 

[sheffester]

And the 4k dollar budget is for this upcoming year, I bought the turbo at the beginning of the year.

 

[xlMcMlx DsM]

Yes it was a stock reman unit from ATK engines in CA.

And as of right now, no tuning. Was just going conservative on everything.

We order(d) engines at work from ATK, and the company was terrible to deal with. We got an engine for a Monte Carlo, and the thing threw a rod not even a mile down the road. That engine combined with no way of tuning is my guess what did it.

 

[Mrdocprofessor]

If your building the motor yourself. 4gs will be a beast

 

[sbeck]

With so many reputable dsm and evo shops why not buy a stock rebuild from a known 4g63 builder instead of places that buy there engines from the lowest bidder? Most large engine and trans suppliers use somewhat local shops as builders as long as they do it cheap enough to still make a profit as a middle man.

 

[josh1095]

i havent read everything but 150 miles isnt too much of a break in. mine is BUILT and i plan on a break in of 2000 miles using maybe 5lbs at the most and very rarely. treat the engine right and make sure the tune is solid. 2 seconds running lean under a heavy load and an engine is toast, serious stuff. i hope ## next build has a better outcome. i had an engine completely rebuilt with forged internals etc.. the whole deal for under 3k. its best to spend the big money upfront and reap the rewards later.
btw, how in the hell would a junk turbo cause a valve to poke thru a piston? just curious, i need educated i guess.....

 

[CrawlinZX14]

Most manufacturers would suggest atleast a 5k mile break in time. The up in the air part is the methods of which you chose to break in the engine.... Oils to use and so on. Personally I run rotella in my break ins for approx 500 miles. That gives it a few solid heat cycles, and the detergents of the rotella tend to help in my experiences. I would run next to no boost for atleast 1k miles. from 1k-2k no more than 5-10psi, 2k-3k miles 10-15psi. Its all about slowly stepping it up.

Most manufacturers suggest proper break in techniques because the heat cycles will basically make the materials stronger and better. Pretty much why most race engine builders will only use seasoned blocks.

They also dont break in engines because their tolerances are much looser than you would want in your daily. Thus the reason break in is not needed. Proper break in helps to seat everything properly and start to season all the internals.

 

[MichaelSuch]

You guys seriously need to read about breaking in your engine. Don't baby it running no boost... Give it factory boost level atleast. Read this. When people like Shep, Rau, guys from English Racing, STM, etc... did they give them an easy break in running little to no boost? Hell no, they tuned it, took it to the track and opened it up. Same way with dirt track guys, and other people that build drag-only cars... Think about it.

 

[1983gsp]

^------I'm with that guy

 

[CrawlinZX14]

You guys seriously need to read about breaking in your engine. Don't baby it running no boost... Give it factory boost level atleast. Read this. When people like Shep, Rau, guys from English Racing, STM, etc... did they give them an easy break in running little to no boost? Hell no, they tuned it, took it to the track and opened it up. Same way with dirt track guys, and other people that build drag-only cars... Think about it.

Obviously your not really thinking about this in an intelligent way nor did you read anything about what I said. Proper break in is for a street driven/ daily driven car. When you build a race engine your break in is normally done during your tuning time. Since a lot of tuners will do so on the dyno. They are also building with far looser tolerances than you would want for a reliable daily driver. They are less worried about off throttle blow by and so on than you would for a daily driven car. There are so many different things you should learn about when it comes to building a race engine than it works for those guys so it should work for my daily driver.

A race engine is not a street engine. DONT compare a race only vehicle to something your planning to street drive. They are two completely different items.

He claims his method works and that he pulled those pistons from an F3. There is no way the one he claimed used his method ever saw combustion. there was absolutely no tarnish above the top ring. And no matter how good your rings seal, your still going to have combustion burns on the crown of the piston. But by all means, use his method and beat your engine. I will look forward to your thread about how something failed and now you need to replace your freshly built motor. The only thing I agree with him on is no synthetic oils during break in.

 

[sbeck]

Once the rings seat they are set which usually only takes a very short time. Once you let it run for 100 miles change the oil. Drive it like you stole it after.

 

[Boostjunki84]

Obviously your not really thinking about this in an intelligent way nor did you read anything about what I said. Proper break in is for a street driven/ daily driven car. When you build a race engine your break in is normally done during your tuning time. Since a lot of tuners will do so on the dyno. They are also building with far looser tolerances than you would want for a reliable daily driver. They are less worried about off throttle blow by and so on than you would for a daily driven car. There are so many different things you should learn about when it comes to building a race engine than it works for those guys so it should work for my daily driver.

A race engine is not a street engine. DONT compare a race only vehicle to something your planning to street drive. They are two completely different items.

He claims his method works and that he pulled those pistons from an F3. There is no way the one he claimed used his method ever saw combustion. there was absolutely no tarnish above the top ring. And no matter how good your rings seal, your still going to have combustion burns on the crown of the piston. But by all means, use his method and beat your engine. I will look forward to your thread about how something failed and now you need to replace your freshly built motor. The only thing I agree with him on is no synthetic oils during break in.

While I understand where you are trying to come from, your rationale is still flawed. Any engine making more than twice the horsepower it came with from the factory, is a race engine and should be treated as such. With most DSMers building their cars for 400+ horsepower, considerations should be made to maximize efficiency and power anyway. In my personal experience, the act of a hard break in has no ill effects on the reliability of the engine itself.


To the OP, while a stock bottom end may handle in the neighborhood of 500hp, since you already have it apart, you might as well build it with better parts. Consider it an opportunity to upgrade. As for why your engine failed, it's least likely that it was due to your break in procedure; especially since the most import part of the break in happens within the first 20 miles.

 

[sheffester]

I am building the motor myself. Josh1095, what components did you use? And to xlMcMlx DsM, this was actually the second engine from them. My first one came improperly timed, even though they told me it was to come timed correctly. It snapped every valve. I called them up and they immediately sent me another unit and a $750 dollar check to compensate me for labor and fluids. So, personally, I had a good experience with them. And like CrawlinZX14 said, just because the valve tested good, doesn't mean it won't fail. I don't blame ATK, I'm just pissed at the situation .

 

[donniekak]

The only reason to baby an engine for hundreds, or thousands of miles is lack of faith in the build. If something is going to let go the first time the boost is turned up it doesn't matter if it's at 5, or 1,000 miles.