Sti 2.5 ECU and pistons
18 October 2012 | 07:55 PM
#32
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From: Pembrokeshire
18 October 2012 | 08:20 PM
#33
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From: 32 cylinders and many cats
This week it has been pouring with rain and the farmers are covering the roads with mud, so I have been driving an almost 9 year old Legacy 3.0R on mud and snow tyres. It probably still has about 241 BHP and cost me £5k a few years ago with 35000 miles in excellent condition. I put 95 RON in it - the cheapest I can find 
I have modified the headlight bulbs.
I have modified the headlight bulbs.
18 October 2012 | 09:16 PM
#34
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From: Pembrokeshire
This week it has been pouring with rain and the farmers are covering the roads with mud, so I have been driving an almost 9 year old Legacy 3.0R on mud and snow tyres. It probably still has about 241 BHP and cost me £5k a few years ago with 35000 miles in excellent condition. I put 95 RON in it - the cheapest I can find I have modified the headlight bulbs.
I have modified the headlight bulbs.
18 October 2012 | 09:43 PM
#35
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From: Enginetuner.co.uk Plymouth Dyno Dynamics RR Engine machining and building EcuTek SimTek mapping
Im new to this i really appreciate the feedback from everyone espically the professionals opinion but i think everyone agree all performance cars aint good value for money or a wise investment the only reason we buy them and have to tunned is passion for love of fast cars 
I've spent endless amounts on motorsport, various pointless road cars, Lambrettas, high maintenance females and booze.
I wasted the rest.
18 October 2012 | 10:18 PM
#36
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From: Enginetuner.co.uk Plymouth Dyno Dynamics RR Engine machining and building EcuTek SimTek mapping
We would use the OE ECU, mapping with Ecutek Race Rom.
A few pictures of a customer's Hatch, due for collection tomorrow.
Engine work, as in forged pistons, rods, ACL bearings, RCM oil pump, ARP studs, Cosworth head gaskets, full engine balance, heads overhauled etc. etc.
And the finished product.
19 October 2012 | 01:58 PM
#39
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From: 32 cylinders and many cats
I'm not an engine builder, my interest is ECUs - reverse engineering, rewriting code, teaching others to tune. So I dislike engines that don't make my tuning look good. The EJ257 is the only one that does that.
Last edited by john banks; 19 October 2012 at 02:02 PM.
19 October 2012 | 08:24 PM
#41
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From: Enginetuner.co.uk Plymouth Dyno Dynamics RR Engine machining and building EcuTek SimTek mapping
19 October 2012 | 08:37 PM
#42
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From: Enginetuner.co.uk Plymouth Dyno Dynamics RR Engine machining and building EcuTek SimTek mapping
A highly stressed 2.5 running close to or over 500 hp will have a reduced life and no matter whose kit you use, the internal engine dynamics are the reason. Apart from the previously mentioned crankcase flex problem.
The Subaru EJ257 is massively ' oversquare ' meaning that the bore is much greater than the stroke length and whilst that is not uncommon in many modern engines, there is a ratio that it is unadviseable to exceed. Piston speed, and piston crown loading come into play and in simplistic terms that is why " a 2.5 won't rev " That is an overstatement, but they are less than happy at over 7000 rpm and will start to creat all sorts of other stresses that leads to engine life expectancy being shortened.
AND of course when you see the dyno traces, there is no need to rev its brains out, as the torque and power curves are long since on the downslope.
Above 7000 on a 2.5 all you are doing is making a lot of noise and wearing out a whole bunch of parts inefficiently.
The Subaru EJ257 is massively ' oversquare ' meaning that the bore is much greater than the stroke length and whilst that is not uncommon in many modern engines, there is a ratio that it is unadviseable to exceed. Piston speed, and piston crown loading come into play and in simplistic terms that is why " a 2.5 won't rev " That is an overstatement, but they are less than happy at over 7000 rpm and will start to creat all sorts of other stresses that leads to engine life expectancy being shortened.
AND of course when you see the dyno traces, there is no need to rev its brains out, as the torque and power curves are long since on the downslope.
Above 7000 on a 2.5 all you are doing is making a lot of noise and wearing out a whole bunch of parts inefficiently.
We built that 2.5 four years ago, (featured May '08 in Japanese Performance) and he's still hammering it about!
Having said that, I agree that there are other routes, and we most often take those instead.
