The 2006 STi Motor that Blew Bits @ the EQ T-Hill Track Day! ...huh?
06-26-2009 | 02:44 PM
#106
Registered User
Joined: Aug 2008
Posts: 551
From: Humboldt CA
Car Info: 2002 WRX
06-26-2009 | 02:47 PM
#107
Former Sponsor
iTrader: (14)
Joined: Sep 2006
Posts: 3,246
From: Hayward, CA
Car Info: WRX, EVO, MSP3
We don't currently use one although do have the car provisioned for one depending on rpm limits the car is going to run.
With the correct oil for high temp track use and adequate engine oil and coolant cooling we do not see pick up starvation in street/moderate track cars as an issue given the relatively low G's in comparison to a out and out track car with significant grip advantage generating extreme cornering G's.
As others have mentioned given the extreme temps serious concideration needs to be given to adequate cooling for the oil, Personally I would stay away from 90% of the bolt on kits out there (just call the guy from Setrab and tell him your engine power output and he'll size a core for you).
There is tons more to this subject but I don't want to dilute this thread so if anyone wants anymore information I would be happy to discuss what our findings have been offline.
Mike
07-06-2009 | 01:27 PM
#116
Big Baller
iTrader: (1)
Joined: Nov 2002
Posts: 1,821
From: Washington
Car Info: 93 BG5, 00&01 GM6, 06LGT, 07STi
Sorry about your loss that sucks.
Combine that with the crappy factory clearances and that's your problem right there.
Not sure if this has been said yet or not, but if your coolant temp is 232, your oil temp is going to be at least 20 degrees higher with average driving loads and much much higher in a race condition. Combine that with high ambient temps and you aren't losing any appreciable amount of heat from the oil pan.
The Subaru oil cooler is actually more of a heater. It raises the oil temp when cold. The coolant in the car heats up faster than the oil. This heat exchanger heats up the oil to an effective and usable state. Then when driving, it keeps the oil temperature under control relatively well. However, it will always be higher than coolant temp once it's warmed up because there has to be a difference in temperature for heat transfer to occur.
In the factory setup, ALL the engines heat loads are being directed to the radiator (oil and coolant heat). Relying on the radiator to handle the load just doesn't work. We build Subaru engines for aircraft and this has been of the biggest hurdles. Everyone advising an oil cooler is correct; it is a great idea. However, be sure the cooler you choose can handle the FLOW needed for this engine. Many of the aftermarket coolers available for our cars actually create a substantial flow restriction and lower oil pressure to the bearings. The bigger the cooler the better (with large lines -10 or larger).
Not sure if this has been said yet or not, but if your coolant temp is 232, your oil temp is going to be at least 20 degrees higher with average driving loads and much much higher in a race condition. Combine that with high ambient temps and you aren't losing any appreciable amount of heat from the oil pan.
The Subaru oil cooler is actually more of a heater. It raises the oil temp when cold. The coolant in the car heats up faster than the oil. This heat exchanger heats up the oil to an effective and usable state. Then when driving, it keeps the oil temperature under control relatively well. However, it will always be higher than coolant temp once it's warmed up because there has to be a difference in temperature for heat transfer to occur.
In the factory setup, ALL the engines heat loads are being directed to the radiator (oil and coolant heat). Relying on the radiator to handle the load just doesn't work. We build Subaru engines for aircraft and this has been of the biggest hurdles. Everyone advising an oil cooler is correct; it is a great idea. However, be sure the cooler you choose can handle the FLOW needed for this engine. Many of the aftermarket coolers available for our cars actually create a substantial flow restriction and lower oil pressure to the bearings. The bigger the cooler the better (with large lines -10 or larger).
07-08-2009 | 04:02 PM
#120
Registered User
Joined: Mar 2008
Posts: 205
From: Making Ed more efficient here there everywhere!
Car Info: 3.2CL Type-S
The tear down pics
Hi Guys,
So everyone was baffled when John Hammer's motor blew up. None of us from EQ had ever seen a motor explode quite like this. There's been a good amount of debate as to why this happened. Here are a few theories we have come up with now that we've taken it apart and seen the damage up close:
1. Rod bearing seized
2. Piston seized in the bore
3. Valve broke and contacted piston
Any of which could be a result of excessive heat and/or oil thinning or starvation.
Here are some pics taken while we dissassembled the motor.
So everyone was baffled when John Hammer's motor blew up. None of us from EQ had ever seen a motor explode quite like this. There's been a good amount of debate as to why this happened. Here are a few theories we have come up with now that we've taken it apart and seen the damage up close:
1. Rod bearing seized
2. Piston seized in the bore
3. Valve broke and contacted piston
Any of which could be a result of excessive heat and/or oil thinning or starvation.
Here are some pics taken while we dissassembled the motor.
Last edited by Sonya@EQTuning; 07-08-2009 at 04:04 PM.