Rebuilding motor, spun a bearing
#1
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Ahh yes, struck down by the ol zoom zoom boom. Last night the car spun a bearing, after installing an EBC and raising the boost from 7-8 psi to around 11. Well it definitely put out a good bit more power (unsure of HP) and felt strong throughout the day including an autocross early on, until a catastrophic failure during a freeway pull in the evening. Car still starts up, but is blowing tons of smoke and making a pretty loud banging around. Im excited to dive in and investigate thoroughly.
l am spoiled enough to have a turbo DD, so I am not left entirely without fun.
nonetheless, i know how much yall like to read of noobs blowing up their $#!7 so here it is haha
I did get 5 years of rough use with the motor, 140k miles about a third are mine, and more track days that I can count on hands and feet. One year of that being boosted. While I couldve stayed at 7-8 psi for a bit longer and not grenaded, the engine was already consuming a good bit of oil and didnt have the best leakdown/compression numbers.
All of that said, and I appreciate your patience, I am now going to build the engine for a predetermined goal. I really want track reliability, not internet points awarding HP. Is a 220-230HP goal pretty reasonable? At that power point, am I better off going higher compression? (Currently 8.8:1)
Heres my current parts list:
Rods
Pistons
Gaskets and Seals etc
BE Oil pump
Headwork (94 head currently, might replace with 99-00)
silicone hoses
flattop or skunk2 mani if head upgrade
still have 3.63 waiting to go in, was pretty damn torquey with the 4.1 and 6spd
Cooling is pretty well sorted, might include an oil cooler and put on more shrouding
any suggestions? I have no engine building experience but I do have a cherry picker. I was gonna pull out the engine and take it to a build shop in the SA area.
l am spoiled enough to have a turbo DD, so I am not left entirely without fun.
nonetheless, i know how much yall like to read of noobs blowing up their $#!7 so here it is haha
I did get 5 years of rough use with the motor, 140k miles about a third are mine, and more track days that I can count on hands and feet. One year of that being boosted. While I couldve stayed at 7-8 psi for a bit longer and not grenaded, the engine was already consuming a good bit of oil and didnt have the best leakdown/compression numbers.
All of that said, and I appreciate your patience, I am now going to build the engine for a predetermined goal. I really want track reliability, not internet points awarding HP. Is a 220-230HP goal pretty reasonable? At that power point, am I better off going higher compression? (Currently 8.8:1)
Heres my current parts list:
Rods
Pistons
Gaskets and Seals etc
BE Oil pump
Headwork (94 head currently, might replace with 99-00)
silicone hoses
flattop or skunk2 mani if head upgrade
still have 3.63 waiting to go in, was pretty damn torquey with the 4.1 and 6spd
Cooling is pretty well sorted, might include an oil cooler and put on more shrouding
any suggestions? I have no engine building experience but I do have a cherry picker. I was gonna pull out the engine and take it to a build shop in the SA area.
#5
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I was also going to ask- how do you know that it’s a spun bearing? Glittery oil is the usual sign. If run long enough, the motor will seize completely. A lot of people run 11 psi without issues, your symptoms don’t sound like a spun bearing.
Seems like there’s a lot of guys here running stock motors at 220-230hp with no issues.
Seems like there’s a lot of guys here running stock motors at 220-230hp with no issues.
#6
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Wont be 100% sure until I dig into it but yes, i think cylinder damage may have occurred. The smoking occurred before the loud failure of the crank bearing. I was in the far left lane of a busy freeway, so I couldnt just shut the car off. The loud clatter began on the exit ramp and and billows of smoke began coming out.
whatever the likely culprit is probably wont change the fact that the block will either need machine work or replacement
the reason i asked about pistons isnt because of the max power goal but because of the power curve goal, would a higher comp (9.5:1) low boost turbo get me what I want?
cant say how much power i was making.. car never saw a dyno which may contributed to the boom. But i have a full 3" exhaust running a 2560 FM2 diy kit. I wanna say that it wasnt from just having an 11 psi stock motor, but more from it being a tired motor and the ebc possibly causing a spike in boost.. i did set a limit in tunerstudio but i think it may have spiked past it
edit: just double checked, had boost limit set to 200kpa or 14.3 psi and it may have gone past that.. i think i may have been tip toeing towards that 250 mark and the tired motor gave up short of it
whatever the likely culprit is probably wont change the fact that the block will either need machine work or replacement
the reason i asked about pistons isnt because of the max power goal but because of the power curve goal, would a higher comp (9.5:1) low boost turbo get me what I want?
cant say how much power i was making.. car never saw a dyno which may contributed to the boom. But i have a full 3" exhaust running a 2560 FM2 diy kit. I wanna say that it wasnt from just having an 11 psi stock motor, but more from it being a tired motor and the ebc possibly causing a spike in boost.. i did set a limit in tunerstudio but i think it may have spiked past it
edit: just double checked, had boost limit set to 200kpa or 14.3 psi and it may have gone past that.. i think i may have been tip toeing towards that 250 mark and the tired motor gave up short of it
#9
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Had afr target of 11.8, redline at 7000, but never made it there. What does it sound more like to you sav? That i ran super lean and snapped a rod and scored the cylinder? Ive never built an engine and luckily this is the first time ive really broken one.
Maybe i burned an exhaust valve, lost my oil that way and ran low on oil until the bearing slipped?
Maybe i burned an exhaust valve, lost my oil that way and ran low on oil until the bearing slipped?
#13
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Lol, you're dancing around the problem. There isn't just one base map, could be anything in there. Your base timing (assuming this is an NA with a CAS) could be off.
Most likely your timing is aggressive and the burning oil from around the rings made it detonate beating the bearings out of it.
Most likely your timing is aggressive and the burning oil from around the rings made it detonate beating the bearings out of it.
#14
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Bronson I think you got it. I used the most logical base map for my vehicle, the turbo tuner base map MM9495, so it wasn't just a random ignition table haha.
At 184 kPA for instance, from 4000-7000 RPM, the igntion timing goes from 14.1 to 16.9 gradually.
Whereas at 100 kPa I am at 28.1-28.8
and sixshooter is right, the car was burning oil and was going to break EVENTUALLY. motors dont last forever, shoot even the highest HP motors sometimes last less than 5 years because of the type of use they see.
At 184 kPA for instance, from 4000-7000 RPM, the igntion timing goes from 14.1 to 16.9 gradually.
Whereas at 100 kPa I am at 28.1-28.8
and sixshooter is right, the car was burning oil and was going to break EVENTUALLY. motors dont last forever, shoot even the highest HP motors sometimes last less than 5 years because of the type of use they see.
#15
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Make all the excuses you want, but your failure mode indicates a tuning error. A well-tuned turbo BP will run until it burns so much oil it no longer needs gas, or until it bends all the rods just a little bit. No HG leaks, no spun bearings, no other problems.
#16
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Sav, im not making excuses i am analytically speculating as to what could have been the cause. I suggested tuning errors in the form of ebc spikes, likely from using a ebc duty table that was too aggr. I suggested oil burning.. it has definitely been getting worse.
i was also on your website speculating a motor build but i wont if your customer service is reflected here in your last comment. I am really trying hard here without the expertise of some of you guys
edit: i will say that i am trying to do things more correct this next time around, learning from some of my mistakes. I think some of the expressed ideas here were spot on. Still figuring out next steps, whether or not to pull the motor or tow to a shop. Whether to build using current compression or higher? And ultimately whether i am better off getting a new long block?
i was also on your website speculating a motor build but i wont if your customer service is reflected here in your last comment. I am really trying hard here without the expertise of some of you guys
edit: i will say that i am trying to do things more correct this next time around, learning from some of my mistakes. I think some of the expressed ideas here were spot on. Still figuring out next steps, whether or not to pull the motor or tow to a shop. Whether to build using current compression or higher? And ultimately whether i am better off getting a new long block?
#17
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I'd hate to see you blow up a second, expensive, built motor because you didn't get your money's worth out of the post-mortem on the first one.
#19
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I have a log from the day before that I will upload. It was right after a firmware update so you'll have to excuse some of the corrections to idle etc.
also, could it just be that I was over the 250HP limit? What mods bring you to that point? I do have a complete 3'' exhaust and dp... any ideas of what kind of power range I may have been operating in?
I had to get the car off the street and up my steep driveway.. I was actually able to get it started this morning and get it up into the garage. Now that it is daylight I can see that the smoke is actually a lot whiter than it is grey, and there is definitely coolant coming out of the exhaust tip. Could this just be a simple HG blowout?
also, could it just be that I was over the 250HP limit? What mods bring you to that point? I do have a complete 3'' exhaust and dp... any ideas of what kind of power range I may have been operating in?
I had to get the car off the street and up my steep driveway.. I was actually able to get it started this morning and get it up into the garage. Now that it is daylight I can see that the smoke is actually a lot whiter than it is grey, and there is definitely coolant coming out of the exhaust tip. Could this just be a simple HG blowout?
#20
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EBC can bite you really fast and easily. Especially if you are using open loop boost, then just temp change can cause you to over boost. I dont think you were over the power limit. If i had to guess i would say a tuning error in the upper boost cells caused a single catastrophic event leading to this