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Old 10-12-2010, 08:57 AM   #1
dapple
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Default Forged Pistons

I have an 07STI 35K, mods GT52 turbo, CAI, TBE, 850cc injectors and protune about 340WHP. I had a problem with cylinder4 cracked piston sleeve. I had that fixed but it still smokes when I step on hard and the inside of my car smells like oil. If I drive the car hard and then let it sit and idle for about 5 mins it starts to smoke. So anyway I am thinking of getting forged pistons. What are some good brands, what kind of rings should I get and will I need to get forged rods as well? Ever since I had these mods done I have had smoking issues. I am afraid to beat on it now in fear it will really let loose. I am going to get a FMI next so they can bump me up to 23PSI boost. But I worry that if I dont get the motor built it will create even more problems after cranking up the HP. Any suggestions or help would br great
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Old 10-12-2010, 10:26 AM   #2
RicersWetDream
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Fix the engine
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Old 10-12-2010, 12:38 PM   #3
soobaviator
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How was the cracked sleeve "fixed"? To my mind that is a new block period. As far as I know most machinist wont even touch an EJ block with a cracked cylinder wall as far as sleeving it...

Forged pistons ain't gonna fix your smokiness... You need to find out exactly what is the cause of the smoking and then you can chose the fix among the applicable options... Your connecting rods are already forged... as are all EJ motor rods...

'07 STI ruined, it's a G-Damn tragedy...




-soobaviator
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Old 10-12-2010, 01:42 PM   #4
al82
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Quote:
Originally Posted by soobaviator
How was the cracked sleeve "fixed"? To my mind that is a new block period. As far as I know most machinist wont even touch an EJ block with a cracked cylinder wall as far as sleeving it...

Forged pistons ain't gonna fix your smokiness... You need to find out exactly what is the cause of the smoking and then you can chose the fix among the applicable options... Your connecting rods are already forged... as are all EJ motor rods...

'07 STI ruined, it's a G-Damn tragedy...

-soobaviator
Time for a new block...check your heads while you at it...I've read about an 07 Sti with a bad valve in one of the heads. Wouldn't hurt to check....

As far as brand of piston, do some searching on the forums about pistons
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Old 10-12-2010, 02:57 PM   #5
dapple
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Quote:
Originally Posted by soobaviator View Post
How was the cracked sleeve "fixed"? To my mind that is a new block period. As far as I know most machinist wont even touch an EJ block with a cracked cylinder wall as far as sleeving it...

Forged pistons ain't gonna fix your smokiness... You need to find out exactly what is the cause of the smoking and then you can chose the fix among the applicable options... Your connecting rods are already forged... as are all EJ motor rods...

'07 STI ruined, it's a G-Damn tragedy...




-soobaviator
Not cracked cylinder just piston and the short block was replaced
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Old 10-12-2010, 03:01 PM   #6
dapple
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Quote:
Originally Posted by al82 View Post
Time for a new block...check your heads while you at it...I've read about an 07 Sti with a bad valve in one of the heads. Wouldn't hurt to check....

As far as brand of piston, do some searching on the forums about pistons
Got a new short block but the problem is back again I mean the smoking. I was told the OEM pistons are not going to be able to handle the power and this would probably happen again. I am thinking of dumping the car but I luv it. The only thing is I am not going to sink 6K to fix this problem
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Old 10-12-2010, 03:01 PM   #7
soobaviator
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Quote:
Originally Posted by dapple View Post
Not cracked cylinder just piston and the short block was replaced
OK...however you did say "cracked piston sleeve". But any case a new short block right? How was it broken in?
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Old 10-12-2010, 11:46 PM   #8
Lucky Strike
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Here let me help you out

Since your unwilling to sink 6g in your car to fix it right.. sell it and buy a rsx type s or civic si. Problemo solved.
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Old 10-15-2010, 04:00 PM   #9
C4NiNjA
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There are too many unanswered questions to even begin to start. Its smoking and you want to buy a TMIC and increase the boost.
Fix the issue or it will get very expensive fase. Was the shortblock you replaced it with new or used? Were the pistons new or used? Did you crack the ringland? If so did you check the compression on the other 3 and if so what were the numbers?
have a compression check and leakdown test on the motor asap. Should not cost ya more then 100-150 bucks. That will tell you alot.

Last edited by C4NiNjA; 10-15-2010 at 04:07 PM.
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Old 10-15-2010, 04:30 PM   #10
kellygnsd
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Quote:
Originally Posted by dapple View Post
Got a new short block but the problem is back again I mean the smoking. I was told the OEM pistons are not going to be able to handle the power and this would probably happen again. I am thinking of dumping the car but I luv it. The only thing is I am not going to sink 6K to fix this problem
Did you get a retune after the first engine went. Chances are if the bad tune killed the first you have what you have now. How long have you been running the newly broken block?
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Old 10-15-2010, 05:18 PM   #11
lcjarrett
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Pistons are the weakest point EJ motors. Next are Bearings.
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Old 10-15-2010, 07:19 PM   #12
dapple
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Originally Posted by soobaviator View Post
OK...however you did say "cracked piston sleeve". But any case a new short block right? How was it broken in?
I meant cracked piston skirt sorry still a newbie
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Old 10-15-2010, 07:23 PM   #13
dapple
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Originally Posted by kellygnsd View Post
Did you get a retune after the first engine went. Chances are if the bad tune killed the first you have what you have now. How long have you been running the newly broken block?
About 3K but been taking it easy cause it doesnt like it if I hammer it. I got a more conservitive tune now so it is ok but I want an aggresive tune next year and with the forged **** i should be ok right
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Old 10-15-2010, 07:28 PM   #14
Lucky Strike
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Yea homie u b aite
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Old 10-15-2010, 11:45 PM   #15
kellygnsd
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Quote:
Originally Posted by dapple View Post
About 3K but been taking it easy cause it doesnt like it if I hammer it. I got a more conservitive tune now so it is ok but I want an aggresive tune next year and with the forged **** i should be ok right
So what your are saying is you didn't get a new tune right after putting the new motor in, the motor wasn't happy when you got on it with the old ****ty tune and you are wondering why you new motor possibly failed too?

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Yea homie u b aite
He will not be aite if the same tuner is hooking him up
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