Daily driver 2.4 or 2.5 project - target 450 BHP/400lbft reliable
IIRC we put the heads on at 2am, yes 2am, after finding that my old heads were knackered, we pulled the spare engine apart, and simply whacked on the heads off that engine fater re seating a valve.
Standard MY00 UK heads.
1.6mm head gaskets on mine.
I suspect John has pushed his a little further in the mid range then i have had time to do, but suspect the top end stuff i could be a littel ahead
.
It will be interesting to see what time will tell.
Steven
Standard MY00 UK heads.
1.6mm head gaskets on mine.
I suspect John has pushed his a little further in the mid range then i have had time to do, but suspect the top end stuff i could be a littel ahead
.It will be interesting to see what time will tell.
Steven
For those that dont know, i have arp standard sized head studs, RCMS Omega Pistons and PAR Rods, rest of the long block is standard.
Upon removing my standard pistons, one of them had 1/10th of a thou clearance!!!
Water temps on the 2.5's climb very quickly indeed, i am about to add an additional fan to my radiator to aid the cooling a little.
Upon removing my standard pistons, one of them had 1/10th of a thou clearance!!!
Water temps on the 2.5's climb very quickly indeed, i am about to add an additional fan to my radiator to aid the cooling a little.
Give it a serious blat, and oil temnps get upo 110 quite easily, even when they sit at 90 on cruise. Water temps, the fan is set to kick in at 96 IIRC and switch off at 92.
A little bit of provocation can have the fans coming in fairly quickly, and taking a while to turn off.
A little bit of provocation can have the fans coming in fairly quickly, and taking a while to turn off.
Just drove (and logged) my first US 2.5 STi today. Stock except for decat and AVC-r running 1.17 bar. Spool point, and torque hit, is simply addicitive - but I wasn't too impressed with mid to top. Not sure how much of a restirction the FBW throttles represent? Also saw very weird timing behaviour - would intermittently swing timing down for no apparent reason. There's no AM to see, but are roughness snensors for each cylinder. Need to educate myself a little.
Basically lots of potential in stock form, needs more work.
Mark @ EMS (if you're reading) - this was Yven's car, I'll email logs later
Richard
Edited to add: the AVC-R needed setting up properly too (disclaimer in case Mark thinks I'm an idjut
)
Basically lots of potential in stock form, needs more work.
Mark @ EMS (if you're reading) - this was Yven's car, I'll email logs later

Richard
Edited to add: the AVC-R needed setting up properly too (disclaimer in case Mark thinks I'm an idjut
)
Richard,
Thanks in advance for the logs!
(E-mail:mark@ems-tuning.nl)
I still have to go to Poland for mapping a US 2.5 for the first time......... (we have to find a date which suits 3 peoples agenda
)
P.S. I don´t think the ECU will pull timing without a reason. (or do you think Subaru will make the same fault twice?
)
Mark.
Thanks in advance for the logs!
(E-mail:mark@ems-tuning.nl)I still have to go to Poland for mapping a US 2.5 for the first time......... (we have to find a date which suits 3 peoples agenda
)P.S. I don´t think the ECU will pull timing without a reason. (or do you think Subaru will make the same fault twice?
)Mark.
Lol, enough said about valve reseating 
Better keep my secret head torque settings to your self!, seems to be working so far (touches wood)!
John are you still using Det cans or KL only to map the car? is your temp sensor definately accurate?
Rob.

Better keep my secret head torque settings to your self!, seems to be working so far (touches wood)!
John are you still using Det cans or KL only to map the car? is your temp sensor definately accurate?
Rob.
Rob, using det cans now and again to confirm the knocklink which is always kept quiet except mapping a bit.
The bolts came out and they were tight - I think Job said 150 Nm, but is was a bad phone line. One side has a failed headgasket, the other side one of the pistons has a small crack, but no bore damage, and no signs of detonation.
I'll get photos and more information when I can.
Present plan is to drop in my spare new EJ257 short motor and run it at lower cylinder pressures (torque).
My earliest thought is that the cylinder pressures with methanol and lots of advance and boost with efficient breathing have been too high for the headgaskets and the pistons.
With a smaller turbo without methanol at lower boost with a more restrictive intake on a conservative dyno I was making 395 lbft (flywheel). From Delta Dash figures I think I was making about 480 BHP and 460 lbft when this failure occurred. There was some light short lived det whilst tuning, but only really the sort you get when finding the edge, so I think I found the limits for this particular example of an EJ257. I think it would last quite well at 450 BHP and 400 lbft which was my original project target, but I think I will turn it down to about 420 BHP and 380 lbft or thereabouts, without using lots of timing, octane and boost. At least there seems to be a limit of the pistons in this situation as well as just the headgaskets. I suspect if these two were sorted at this level the next issue could be bearings or something else LOL.
The bolts came out and they were tight - I think Job said 150 Nm, but is was a bad phone line. One side has a failed headgasket, the other side one of the pistons has a small crack, but no bore damage, and no signs of detonation.
I'll get photos and more information when I can.
Present plan is to drop in my spare new EJ257 short motor and run it at lower cylinder pressures (torque).
My earliest thought is that the cylinder pressures with methanol and lots of advance and boost with efficient breathing have been too high for the headgaskets and the pistons.
With a smaller turbo without methanol at lower boost with a more restrictive intake on a conservative dyno I was making 395 lbft (flywheel). From Delta Dash figures I think I was making about 480 BHP and 460 lbft when this failure occurred. There was some light short lived det whilst tuning, but only really the sort you get when finding the edge, so I think I found the limits for this particular example of an EJ257. I think it would last quite well at 450 BHP and 400 lbft which was my original project target, but I think I will turn it down to about 420 BHP and 380 lbft or thereabouts, without using lots of timing, octane and boost. At least there seems to be a limit of the pistons in this situation as well as just the headgaskets. I suspect if these two were sorted at this level the next issue could be bearings or something else LOL.
What colour was the water John?
Stupidly been fiddling with mine, and hit (cough) 1.8bar (cough) on a couple of occassions this morning, think i will be reverting back to 1.6, as i scared the sh1te out of myself!
Water and oil levels are fine, just have a slight tangoing of the water, and header tank.
Stupidly been fiddling with mine, and hit (cough) 1.8bar (cough) on a couple of occassions this morning, think i will be reverting back to 1.6, as i scared the sh1te out of myself!
Water and oil levels are fine, just have a slight tangoing of the water, and header tank.
Water
, and i cant remember the antifreeze make, as i lent Trout the bottle i have, will have to get it off him tonight.
Thinking about it, its probably not got enough antifreeze in, as i lost a lot of water when i had the turbo off a couple of times, and could not add antifreeze due to not knowing where the bottle was.
Will have to get some more, what would you use rob? Will be passing Halfords on way home.
, and i cant remember the antifreeze make, as i lent Trout the bottle i have, will have to get it off him tonight.Thinking about it, its probably not got enough antifreeze in, as i lost a lot of water when i had the turbo off a couple of times, and could not add antifreeze due to not knowing where the bottle was.
Will have to get some more, what would you use rob? Will be passing Halfords on way home.
Only if I can hold the headgaskets down though? If I knew I could then I would and possibly will uprate the internals.
There do seem to be as many opinions as there are options.
Some say that 12mm studs are the way forward, 14mm don't clamp better and get too near the water jackets.
Others find differences between gaskets and small changes in clamping pressure.
Some blame temperatures even though the oil and coolant never got that hot. Some say despite that I need an uprated rad cap to stop localised boiling. Some say use water wetter, some not.
Some say I should run less timing and more boost to get the torque, but then what do I do about the EGTs that go through the roof?
Some say try thicker heads, some O-rings.
Did the edge of the piston get a small crack from cylinder pressure and/or detonation, or did it do it because the head gaskets leaked on the other side of the engine and there was air in the water system leading to overheating?
Who's actually done it and had it last on this engine? Er...
As T-uk says there is only one proven method to cut hassle for a while, turn it down. Otherwise I'll be chasing the failure point all round the engine in the never ending quest for the next fix of torque or power
Had I carefully stuck to my project goals instead of tuning it up to be a dyno queen next weekend it would all have been hunky dory
At least I'm honest
There do seem to be as many opinions as there are options.
Some say that 12mm studs are the way forward, 14mm don't clamp better and get too near the water jackets.
Others find differences between gaskets and small changes in clamping pressure.
Some blame temperatures even though the oil and coolant never got that hot. Some say despite that I need an uprated rad cap to stop localised boiling. Some say use water wetter, some not.
Some say I should run less timing and more boost to get the torque, but then what do I do about the EGTs that go through the roof?
Some say try thicker heads, some O-rings.
Did the edge of the piston get a small crack from cylinder pressure and/or detonation, or did it do it because the head gaskets leaked on the other side of the engine and there was air in the water system leading to overheating?
Who's actually done it and had it last on this engine? Er...
As T-uk says there is only one proven method to cut hassle for a while, turn it down. Otherwise I'll be chasing the failure point all round the engine in the never ending quest for the next fix of torque or power

Had I carefully stuck to my project goals instead of tuning it up to be a dyno queen next weekend it would all have been hunky dory

At least I'm honest
Subaru Tuning Specialist
Joined: Jun 2002
Posts: 6,654
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From: 7.74 @179 mph 1/4 mile - road legal
The good news for this dyno queen is that I can now turn my boost down knowing JB will not be er 'competing' 
oops, quick rethink, I see Callum is entered with his RCM 2.5 !

oops, quick rethink, I see Callum is entered with his RCM 2.5 !
Last edited by Andy.F; Aug 12, 2004 at 11:24 AM.
LMAO 
John - 150NM is 110lb/ft
....hope you/Job were mistaken! Can you check?
I'm planning to torque down my heads to max 85lb/ft - and my builder is nervous about that (he's used to Porsche's, which have a max torque of ~40lb/ft before damage occurs apparently).
Richard

John - 150NM is 110lb/ft
....hope you/Job were mistaken! Can you check?I'm planning to torque down my heads to max 85lb/ft - and my builder is nervous about that (he's used to Porsche's, which have a max torque of ~40lb/ft before damage occurs apparently).
Richard
160Nm Richard, just spoke to Job. This is bolts of course.
Competitive Andy, but never the Queen whilst you are around anyway, so why do I bother, only costs me money
Mind you I'm still pretty new at this game
Competitive Andy, but never the Queen whilst you are around anyway, so why do I bother, only costs me money
Mind you I'm still pretty new at this game
Steven, can highly reccomend Halfords All season Antifreeze, best i have used.. for water temps and engine protection(bright red fluid, blue container).
Lack of Antifreeze will deffo explain orange water, better get the AF in asap.
What damage if there to the gasket john?
Rob
Lack of Antifreeze will deffo explain orange water, better get the AF in asap.
What damage if there to the gasket john?
Rob
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Joined: Nov 2001
Posts: 15,239
Likes: 1
From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
infact.. pull the new 257 to bits.. fit the rods and pistons to the old engine, and refit that if you dont want to play yet, that leaves you two working engines ish... fit new rods and pistons to new block then swap over, thus removing a working engine... instead of ending up with two broken engines
No David. I presume they are OK since they haven't picked up in the bores.
I'll get some pictures of the gaskets and the cracked piston later when I go to see it in hospital, sorry the garage
Will be taking the new short motor there tonight to get started on tomorrow, so might be up and running in
(Andy F style of course) fairly soon.
New engine has three A pistons and one B. I think the original had more Bs, will take photos later.
I'll get some pictures of the gaskets and the cracked piston later when I go to see it in hospital, sorry the garage
Will be taking the new short motor there tonight to get started on tomorrow, so might be up and running in
(Andy F style of course) fairly soon.New engine has three A pistons and one B. I think the original had more Bs, will take photos later.



