OFFICIAL Blown 4-banger build updates!
04-08-2009, 09:25 PM
#2426
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I thought you just needed new lifters/valvetrain?
I hope you didn't pull the motor just for that...
Or did something else fail? I have never facepalmed anyone more than you and Ralliartist over how you guys fail at modding cars.
I hope you didn't pull the motor just for that...
Or did something else fail? I have never facepalmed anyone more than you and Ralliartist over how you guys fail at modding cars.
04-09-2009, 12:26 AM
#2428
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P.S. I didn't pull the engine for lifters.
Everything with my engine was done properly. It was a series of things stupidly going wrong that cause the issue that made me pull the engine.
After reading your PM, you are officially off my haterade list.
04-09-2009, 12:41 AM
#2429
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Uh huh... Perfect sense. I believe if it was done properly, you would be driving the car, no?
04-14-2009, 01:05 AM
#2433
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Well, I was planning on keeping this under wraps, but **** it. I don't care anymore. So I tore the motor down today. Number 1 and 4 rod bearings were pristine, number 2 bearing was scored pretty good, would have been destroyed in a couple minutes had the engine been left running. Number 3 rod bearing was mostly in powder form at the bottom of the oil pan. Some of it was still hanging on to the crank journal.
Here is the oil pan, decorated nicely with bearing powder and oil. I like to call it, Magnetic Mud
Here are some of the larger pieces of bearing left in the oil pan.
Here is the largest piece of bearing recovered. Pretty!
Due to the thrashing (while brief) from the rod, the corresponding main bearings were punished pretty good. Crank is fine, all 4 rods and pistons are fine. The head gasket was showing signs of trying to blow (been reused some 4 times, it lived a nice life.... *moment of silence), so new head gasket will be needed. Other than that, everything else was peachy. Valvetrain was untouched.
The cause of failure has been determined as moderate to severe detonation in cylinders 2 and 3. The Pistons (while still healthy) took quite a beating from detonation, and the spark plugs were ghost white. Strangely though, cylinders 1 and 4 were the opposite. Pistons showed signs of running stupid rich, and spark plugs were black. My wideband is closest to the #4 cylinder, and it showed it as running rich. My EGT sensor was in the #4 primary, and showed readings that went along with running rich. However, since the second my engine came to life the second time, my O2 sensor never worked. I checked all wires, I cleaned it, I even got a new one. Nothing. It never worked. So we pretty much came to the conclusion, that the computer was for some reason running 1 and 4 uber rich, and 2 and 3 uber lean (causing detonation). I only had the car running 13-15 degrees of timing. So, its the only explanation I can come up with at this point. So, it was 100% not assembly error. ENGINE WAS ASSEMBLED PROPERLY AS STATED BEFORE!!! So there is my latest update, enjoy
Here is the oil pan, decorated nicely with bearing powder and oil. I like to call it, Magnetic Mud
Here are some of the larger pieces of bearing left in the oil pan.
Here is the largest piece of bearing recovered. Pretty!
Due to the thrashing (while brief) from the rod, the corresponding main bearings were punished pretty good. Crank is fine, all 4 rods and pistons are fine. The head gasket was showing signs of trying to blow (been reused some 4 times, it lived a nice life.... *moment of silence), so new head gasket will be needed. Other than that, everything else was peachy. Valvetrain was untouched.
The cause of failure has been determined as moderate to severe detonation in cylinders 2 and 3. The Pistons (while still healthy) took quite a beating from detonation, and the spark plugs were ghost white. Strangely though, cylinders 1 and 4 were the opposite. Pistons showed signs of running stupid rich, and spark plugs were black. My wideband is closest to the #4 cylinder, and it showed it as running rich. My EGT sensor was in the #4 primary, and showed readings that went along with running rich. However, since the second my engine came to life the second time, my O2 sensor never worked. I checked all wires, I cleaned it, I even got a new one. Nothing. It never worked. So we pretty much came to the conclusion, that the computer was for some reason running 1 and 4 uber rich, and 2 and 3 uber lean (causing detonation). I only had the car running 13-15 degrees of timing. So, its the only explanation I can come up with at this point. So, it was 100% not assembly error. ENGINE WAS ASSEMBLED PROPERLY AS STATED BEFORE!!! So there is my latest update, enjoy
04-14-2009, 12:14 PM
#2435
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I guess there is always some positive to the negative. Its only gonna cost me like $180-200 to get it back together. All machine work will be labor free, so thats also a plus.
04-14-2009, 03:10 PM
#2437
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We didn't do that, as far as I know. I'm gonna take the injectors to a local shop, and have then checked to make sure there not fucked up. Then I'll probably sell them, because I'm gonna use stock injectors while NA, and when I go turbo I'll use 83 lbs/hr injectors. So the 60s will be retired.
04-14-2009, 09:28 PM
#2439
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In order to put the coils in different spots, it would require cutting and resizing the harness We didn't do that, as far as I know. I'm gonna take the injectors to a local shop, and have then checked to make sure there not fucked up. Then I'll probably sell them, because I'm gonna use stock injectors while NA, and when I go turbo I'll use 83 lbs/hr injectors. So the 60s will be retired.
We didn't do that, as far as I know. I'm gonna take the injectors to a local shop, and have then checked to make sure there not fucked up. Then I'll probably sell them, because I'm gonna use stock injectors while NA, and when I go turbo I'll use 83 lbs/hr injectors. So the 60s will be retired.if you had the cash it would be 10000000000x better to run some secondary injectors.
04-16-2009, 03:12 AM
#2440
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No it wouldn't. Race cars don't use secondary injectors. The cobalt isn't my DD anymore (thats what my AE86 is for), so I don't give a **** about drivability, or gas mileage anymore (not that I did in the first place).
04-16-2009, 08:28 AM
#2442
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They sat in my room, sealed in a zip lock bag, for the entire time my car was down.
No it wouldn't. Race cars don't use secondary injectors. The cobalt isn't my DD anymore (thats what my AE86 is for), so I don't give a **** about drivability, or gas mileage anymore (not that I did in the first place).
No it wouldn't. Race cars don't use secondary injectors. The cobalt isn't my DD anymore (thats what my AE86 is for), so I don't give a **** about drivability, or gas mileage anymore (not that I did in the first place).
04-16-2009, 01:06 PM
#2444
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Yeah, but that doesn't matter. The problem with huge injectors, is they have a minimum pulse width that is longer than what the car needs to maintain a 14.7:1 AFR at idle, so the injectors idle at minimum pulse width, but the car still runs really rich at idle. There are some 1400 RWHP Supras out here in AZ, they use giant ass injectors, and idle at 11.5-12:1 afr.
Cause I'm cheap, and the gasket was given to me. It was a cometic yes. I'm just gonna get another cometic.
04-16-2009, 03:02 PM
#2445
No. I didn't know you had to clean them out before storing them. If they worked when I pulled them out, I didn't see any reason they wouldn't work after sitting in a sealed clean plastic bag
Yeah, but that doesn't matter. The problem with huge injectors, is they have a minimum pulse width that is longer than what the car needs to maintain a 14.7:1 AFR at idle, so the injectors idle at minimum pulse width, but the car still runs really rich at idle. There are some 1400 RWHP Supras out here in AZ, they use giant ass injectors, and idle at 11.5-12:1 afr.
Cause I'm cheap, and the gasket was given to me. It was a cometic yes. I'm just gonna get another cometic.
Yeah, but that doesn't matter. The problem with huge injectors, is they have a minimum pulse width that is longer than what the car needs to maintain a 14.7:1 AFR at idle, so the injectors idle at minimum pulse width, but the car still runs really rich at idle. There are some 1400 RWHP Supras out here in AZ, they use giant ass injectors, and idle at 11.5-12:1 afr.
Cause I'm cheap, and the gasket was given to me. It was a cometic yes. I'm just gonna get another cometic.
YEah you really need to completely drain injectors before storing them for extended periods of time or they "gum" up.
As for large injectors, the 79lb/hr ones I run idle better than stock, but anything more than that is pretty shitty for low PW idle.
THat's also why I run 550cc primary and 1600cc secondaries in my rx-7, still idle it @12.4-12.5:1 afr.
06-30-2009, 09:47 PM
#2449
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I've not read anything but the first and last page of this thread. But in response to the statement that 1 & 4 were rich and 2-3 were stupid lean.
When i put my 60# injectors in i had what sounded like an air leak, but couldn't find it, so i decided it was just a noise the new injectors made. Tuned it to my desired afr..
Like a week later i had my dad listen to the sound, and he suggested i pull the injectors back out and check the o-rings. Turns out two of the o-rings on the injector cups had been pinched and were sucking air around them. I had a similar plug reading (2 rich, 2 lean). So when i replaced the o-rings, my wot afr went from 11.8 to off the scale rich (below 10.0)..
Perhaps something similar happened to you?
When i put my 60# injectors in i had what sounded like an air leak, but couldn't find it, so i decided it was just a noise the new injectors made. Tuned it to my desired afr..
Like a week later i had my dad listen to the sound, and he suggested i pull the injectors back out and check the o-rings. Turns out two of the o-rings on the injector cups had been pinched and were sucking air around them. I had a similar plug reading (2 rich, 2 lean). So when i replaced the o-rings, my wot afr went from 11.8 to off the scale rich (below 10.0)..
Perhaps something similar happened to you?
