2.5 engine ?
#31
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I have a zen built 2.5 in my blob mated to a garret gt30 and it's a perfect fast road car, no lag and oodles of low end grunt. Such a shame it's not been decked/pinned as i would love to get over 500 but been advised against going over 475 on a scdb 2.5. There are a few over 500 but I think it's in the hands of God
#32
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#48
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Biggest problem with 2.5s is the drive by wire which is like having a ******* with a sock on your ****.... Add to the the rubbish seating in 05-07 cars and the internationally criticised 2.5 unit....the safe bet is always 2 litre and JDM even better ....Hatches onward are an awesome car to sit in but UK reliability is a huge concern even in standard cars. I know lots of people with standard cars and expertly modified ones that have perished well before acceptable manufacturing standards should allow.
Last edited by 53; 20 January 2015 at 09:36 PM.
#49
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Biggest problem with 2.5s is the drive by wire which is like having a ******* with a sock on your ****.... Add to the the rubbish seating in 05-07 cars and the internationally criticised 2.5 unit....the safe bet is always 2 litre and JDM even better ....Hatches onward are an awesome car to sit in but UK reliability is a huge concern even in standard cars. I know lots of people with standard cars and expertly modified ones that have perished well before acceptable manufacturing standards should allow.
#50
Scooby Regular
More on the EJ #3 failures.
While we have gradually discovered how much power an internally stock EJ20 can handle, we've been lucky enough to see others in the industry blow up engines instead of blowing up our own. This allowed us to learn the lesson without paying the tuition (cost of rebuild). One major flaw we've uncovered in the EJ20 isn't in its awkward boxer design, but the routing of the turbo system.
On most of the blown-up Subarus we've seen, we noticed the number three cylinder has often been the dead leg in the engine. Every blown engine I've ever witnessed has either thrown a rod out the block, bent a rod, melted a piston or even cracked the ring lands--all on the number three cylinder.
The turbo is on the passenger side of the engine and the number three cylinder happens to also be on the rear passenger side. One of the theories hinges on the manner in which the turbo, up-pipe and downpipe are encased around the number three cylinder. This causes an abundant amount of heat to concentrate on this one cylinder, potentially over-heating it.
Regardless of the design flaw, there are a couple of equally critical issues that should be addressed on the U.S.-spec EJ20 engine: The factory pistons are cast aluminum and the rods aren't ready for big boost. That brings us to our EJ20 build-up.
Mike Morita from Sparco has a black WRX (featured in the January 2002 issue of Turbo) and just as his car was building more power, the number three cylinder "remolded" the cast piston while also breaking the ring lands.
The engine was pulled and disassembled, with the internal parts sent to HKS and the block and heads sent to RS Machine in Torrance, Calif. Here, Mike Coughtrie worked his magic on the block. Not just your average machine shop, this place is geared for high performance. While Mike was busy machining the engine, HKS was busy lining up the rest of the parts.
Scrapping the inferior EJ internals for much better aftermarket units, the HKS R&D team decided to go with Arias Pistons and Crower connecting rods. Of course, once the engine is assembled, it'll also receive an arsenal of HKS parts, including an upgraded turbo and engine management.
When the engine was disassembled, a cracked combustion chamber was discovered. Naturally, this occurred in the number three chamber. While HKS was managing to get hold of bearings, gaskets and other accessories, the block was nearly finished.
Follow along to see what was done to prep the block for big boost, then check in a future issue for our follow-up article, which will focus on assembly and testing.
On most of the blown-up Subarus we've seen, we noticed the number three cylinder has often been the dead leg in the engine. Every blown engine I've ever witnessed has either thrown a rod out the block, bent a rod, melted a piston or even cracked the ring lands--all on the number three cylinder.
The turbo is on the passenger side of the engine and the number three cylinder happens to also be on the rear passenger side. One of the theories hinges on the manner in which the turbo, up-pipe and downpipe are encased around the number three cylinder. This causes an abundant amount of heat to concentrate on this one cylinder, potentially over-heating it.
Regardless of the design flaw, there are a couple of equally critical issues that should be addressed on the U.S.-spec EJ20 engine: The factory pistons are cast aluminum and the rods aren't ready for big boost. That brings us to our EJ20 build-up.
Mike Morita from Sparco has a black WRX (featured in the January 2002 issue of Turbo) and just as his car was building more power, the number three cylinder "remolded" the cast piston while also breaking the ring lands.
The engine was pulled and disassembled, with the internal parts sent to HKS and the block and heads sent to RS Machine in Torrance, Calif. Here, Mike Coughtrie worked his magic on the block. Not just your average machine shop, this place is geared for high performance. While Mike was busy machining the engine, HKS was busy lining up the rest of the parts.
Scrapping the inferior EJ internals for much better aftermarket units, the HKS R&D team decided to go with Arias Pistons and Crower connecting rods. Of course, once the engine is assembled, it'll also receive an arsenal of HKS parts, including an upgraded turbo and engine management.
When the engine was disassembled, a cracked combustion chamber was discovered. Naturally, this occurred in the number three chamber. While HKS was managing to get hold of bearings, gaskets and other accessories, the block was nearly finished.
Follow along to see what was done to prep the block for big boost, then check in a future issue for our follow-up article, which will focus on assembly and testing.
Ironically my compression print out shows failure on just #1 and #3
EDIT: #1 Failing due to a piece of sparkplug breaking off.
Last edited by RS_Matt; 25 January 2015 at 02:07 PM.
#51
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I think they meant those that don't have a suspect stock/aftermarket tune that makes 2 and 4 lean. Basically if an Impreza has the right tune then the weak point is #3. Obviously the #3 vulnerability is exacerbated on a 2.5 as the engine expels more hot gases.
More on the EJ #3 failures.
Read more: http://www.superstreetonline.com/how...#ixzz3PStz2TmG
Ironically my compression print out shows failure on just #1 and #3
More on the EJ #3 failures.
Read more: http://www.superstreetonline.com/how...#ixzz3PStz2TmG
Ironically my compression print out shows failure on just #1 and #3
#57
Scooby Regular
iTrader: (2)
I think they meant those that don't have a suspect stock/aftermarket tune that makes 2 and 4 lean. Basically if an Impreza has the right tune then the weak point is #3. Obviously the #3 vulnerability is exacerbated on a 2.5 as the engine expels more hot gases.
More on the EJ #3 failures.
Read more: http://www.superstreetonline.com/how...#ixzz3PStz2TmG
Ironically my compression print out shows failure on just #1 and #3
More on the EJ #3 failures.
Read more: http://www.superstreetonline.com/how...#ixzz3PStz2TmG
Ironically my compression print out shows failure on just #1 and #3
The sooner you stop looking on US sites the better, reading & quoting other peoples issues without fully understanding the spec of the engine the fuel its using, which in the US is the biggest issue.