Asphalt Assault

Moderator can sticky or move this where you please.

EDIT: I did not include a important note about being respectful here. We should always be that way. Were all trying to learn.


I have been researching for all blown motors out there. I cant seem to find all the threads that are out there. can all of you help.

1. Post with thread that you found with someone with a blown motor.
2. if you have a blown motor please post here. can you tell us what was the demise of the engine.

Thankyou everyone. I know of one post that I just read.
https://www.cobaltss.net/forums/advanced-performance-modifications-130/8-5-1-pistons-52275/

blown06

i blew mine on the dyno, i believe it is the ringland I will now more this weekend when I pull the head. I believe it was a result of rob's tune. when they opened the file on my car it was a mess and was surprised that my car didnt go sooner than it did.

BlackSS/SC

What was messed up in that tune?

dstinsman56

I blew my motor on race gas Blew the number four piston ringland
Here a couple pics

Asphalt Assault

I have a few questions as I dont want to assume.

did the Tune come from the repository on HPTUNERS?
Did you load it and run with it?

IMO all cars are different even the same make. GM TUNE is generic and runs rich for that reason I believe. I would like to think that we can take someone elses tune to compare to our own in order to learn how to tweak our own tune. Learn from it.

What mods to did you run? what was your boost at? At what RPM did it start to fail? any warning signs like a decrease in power? What was your pulley size?


Wow I am looking at your mode list. - do you think it was due to boost to high with 2.6"?
I also see no exhaust mods other than a hollowed cat? What was your AFR? did you ever tune it to aim for a certain AFR? Considering your WHP it is getting close to the 350hp that the pistons are rated for.

2.6" pulley 7 60 0 Sun Jan 14, 2007 19:26 Sun Jan 14, 2007 19:26
3 inch tensioner pulley 10 20 0 Sun Aug 27, 2006 1:38 Sun Aug 27, 2006 1:46
60lbs/hr injectors 10 260 0 Sun Aug 27, 2006 1:32 Sun Aug 27, 2006 1:49
Adjustable tensioner 0 108 0 Sun Aug 27, 2006 1:45 Sun Aug 27, 2006 18:41
ARP Headstuds 0 131 0 Sat Feb 03, 2007 11:59 Sat Feb 03, 2007 11:59
cobra heat exchanger 0 60 0 Fri Mar 02, 2007 21:33 Fri Mar 02, 2007 21:33
Colder Plugs 10 8 0 Sun Aug 27, 2006 1:37 Sun Aug 27, 2006 1:37
Cometic Head Gasket 0 80 0 Sat Feb 03, 2007 12:00 Sat Feb 03, 2007 12:00
Diamond Pistons 0 620 0 Sat Feb 03, 2007 11:57 Sat Feb 03, 2007 11:57
Hollowed Cat 7 0 0 Tue Oct 03, 2006 20:55 Wed Oct 04, 2006 18:45
Injector Harness 10 50 0 Sun Aug 27, 2006 1:36 Sun Aug 27, 2006 1:36
Intercepter Scan Gauge 10 229 0 Sun Dec 24, 2006 18:42 Sun Dec 24, 2006 18:42
K&N Intake 6 224 0 Sat Jul 22, 2006 15:53 Sat Jul 22, 2006 15:53
Machined Snout 10 70 0 Sun Aug 27, 2006 1:40 Sun Aug 27, 2006 1:40
Magnaflow Catback Exhaust 0 660 0 Sat Jul 22, 2006 15:52 Sat Jul 22, 2006 15:54
Modular Pulley system 10 100 0 Sun Aug 27, 2006 1:34 Sun Jan 14, 2007 19:25
PSYKOTUNED VCM (STAGE 5) 10 100 0 Sun Aug 27, 2006 1:35 Thu Aug 31, 2006 7:03
Stage 2 belt 10 45 0 Sun Aug 27, 2006 1:42 Sun Aug 27, 2006 1:42

BlackSS/SC

I'd never run a tune off the repository! Like ssnipes said every car is different.

dstinsman56

Some of these mods where not on the car when I blew the motor. I had been running a stage 4 from intense for about a 6 months and a tune to eliminate some of the knock, but living in arizona summer came around and so did the knock, and then boom! All I had for exhaust was a magnaflow catback and hollowed cat. They were stock pistons and no studs or gasket yet. Also no cooling mods that I should have had at them time. I am installing the cobra heat exchanger and dual pass along with meth before I ever crank it over after the rebuild

slowbalt19

blew my motor https://www.cobaltss.net/forums/general-cobalt-68/motor-fixable-53835/

Asphalt Assault

Great post and great summary. Thankyou.

Man that makes me sick just looking at the carnage and oil. so graphic with the balance shaft sticking out. Warn me next time for a thread like that guys. My kids almost saw it. would have traumatized them for life. I will never be the same for sure.

How is the car now?

SKDR112888

holy ****!! lol

I like the guy that said "JBweld will do it, Its only cosmetic damage "

Cobalt443

I blew my 2.4 with only 381 miles on it! I was bringing it back to the dealer in PA to have factory paint defects taken car of. About 4 miles before my exit, it wouldn't rev passed 4k and my coolant temp wasn't reading at all.

I ended up cracking the block, warping the head, and melting the number 4 piston....all because a coolant hose wasn't put on right

blown06

apparently there was a section that went really lean apparently 12-13a/f and he tuned it with 24-25* timing.... apparently with his tune I have recently found out that 6 motors have been blown which I just found out within the last couple of weeks

BlackSS/SC

That's a lot of timing, must have been race gas tune. And the a/f ratio you gotta tune that for each and every car. You probably know that though.

07cobaltowner

well i didn't blow a cobalt but i have blawn 2 motors. both were on my 1990 toyota celica gts.
first one blew cause the car overheated due to clogged radiator, and spun a bearing (was my first car didn't know **** about them at 16)
the next motor was crated in and my freinds and i did the swap. bought new radiator, pipes and gaskets, timing belt, water pump, clutch, flywheel, flex pipe. we swapped everything over to the new motor, put it in hooked it up, and i swear to GOD i didn't try to start it.
had it towed to a shop, they were the ones who started it up after 1000$ bill.
month or so later engine shuts itself off cause it overheated. apparently my gauge was broken. okay so far no damage see that oil pan is leaking. get it off then see holy ****! the oil pump was so warped it was rediculous.
replaced it and thought the motor was fine but it had already done its damage. another spun bearing and that car was fcked.
the company i bought it from woudn;t honor the warranty casue it didn't have a heat tab(a little thing that burns out when engine block overheats) even though i had a picture that if you looked close you could see it was never there when i bought the engine(didn't know about it at the time)
so that was about 10,000$ wasted (im including price of car, shop fees, towing fees[11times], insurance, parts, etc...)

Asphalt Assault

Nice.... but can we stay on topic. it is a blown COBALT thread. If you read about someone blowing up a cobalt on this forum then paste the link to the thread, or if you blew up your cobalt then lets talk.

thanks

blown06

https://www.cobaltss.net/forums/showthread.php?t=52275

beamSS

https://www.cobaltss.net/forums/problems-service-maintenance-69/another-cobalt-down-engine-blown-45889/

WSFrazier

I blew my ringland on #4 piston as well. Been running Dan.spec tune for months with the 2.5"/60# setup. As soon as we went to change it, boom. So FYI, Dan.spec's are safe, lol.

beamSS

blew mine with 2.8 and 60# running 18* timing. tuned @ 40ish weather. blew @ 0* weather so maybe i went lean? idk

pimpnwink

iTrader: (1)

What ive been noticing with all of these blown engine threads is that its always piston #4 is that due to it being at the end (beginning not sure) of the fuel rail or another reason. I know it was discussed somewhere but i dont remember and i dont feel like searching.

SStud

Something indeed is causing premature blowing (Pauses for a good laugh ). Deffinetly needs some serious looking into.

Dave

BlackSS/SC

Ya we gotta find out what to do about all this blowing of the #4.

Blown 4-banger

Your going to find out that pretty much EVERY blown motor out there is gonna be the #4 ringland. Just like my car, that stupid little **** can't handle the pressure. I ******* hate GM

BlackSS/SC

So when you blow a ring land, does if **** the sleve up too? or does is all depend?

rickyw

bump for a good question