Lads last year I blew my engine on 08 new shape Wrx Impreza , was building my house so had to leave all my cars alone till mortgage was sorted but now I want to push on and get back on the road but I don’t know what way to go , the 2.5 are a weak engine With overheating issues and if I’m appending money getting full rebuild am I better off going with a ej20 , have been on to rcm in England and had sourced brand new bottom end with uprated piston Conrods and Other bits on it through them but would have to get a new head and then get it fully rebuilt mapped and everything else , my question is do I plow on and go with the 2.5 l or go with a uprated ej20 engine , any opinions great appreciated as in will I have issues with ecus anything going with a ej20 I have 2 ej20 there in good condition so maybe could use one of them any work is hopefully going to be down by westward engineering but as people on here living with Subaru’s I said I would ask
2.5 l or 2.0 engine ???
- Thread starter redlad81
- Start date
Keadeen
Well-known member
A built 2.5 will be as strong as a built 2.0 - provided the right parts a chosen, studs uprated, uprated pistons, etc etc.
As it is an '08 hatch - is it in the €2350 road tax bracket?
If so, it won't make any difference for road tax as will be on emissions instead of capacity anyway.
So, it comes down to whether you want to lowdown torque of the 2.5 option vs the high rev "singing" of the 2.0...
-what's you preference torque / high revs? (and keep in mind that building either 2.0 or 2.5 would allow you to pick some parts to mitigate to worst downside of either)
-how will you use the car? (road use mainly then maybe 2.5 is a "nicer" drive, but if doing loads of racing / trackdays where the engine will sit at high RPM a lot maybe 2.0)
If you had a 2.5 before in that car than personally I'd probably stick with it. Less hassle sorting out wiring loom issues / sensors etc... and if building an engine there's no saying going with one or the other really - and as both would be strong after a proper build it shouldn't make a difference reliability wise either. Good luck with the journey... will cost a bit (always more than you think), and if going there than the moto deffo should be "do it once, do it right" as a half rebuild doesn't give you the reliability you'd want out of the hassle and expense of a built engine.... but once done right, you know what you have.
As it is an '08 hatch - is it in the €2350 road tax bracket?
If so, it won't make any difference for road tax as will be on emissions instead of capacity anyway.
So, it comes down to whether you want to lowdown torque of the 2.5 option vs the high rev "singing" of the 2.0...
-what's you preference torque / high revs? (and keep in mind that building either 2.0 or 2.5 would allow you to pick some parts to mitigate to worst downside of either)
-how will you use the car? (road use mainly then maybe 2.5 is a "nicer" drive, but if doing loads of racing / trackdays where the engine will sit at high RPM a lot maybe 2.0)
If you had a 2.5 before in that car than personally I'd probably stick with it. Less hassle sorting out wiring loom issues / sensors etc... and if building an engine there's no saying going with one or the other really - and as both would be strong after a proper build it shouldn't make a difference reliability wise either. Good luck with the journey... will cost a bit (always more than you think), and if going there than the moto deffo should be "do it once, do it right" as a half rebuild doesn't give you the reliability you'd want out of the hassle and expense of a built engine.... but once done right, you know what you have.
Sheriff
Octane Boostaholics
its a 07 hatch 08/11 wrx so cheaper tax i would rather stay with a 2.5 myself i actually bought a second hand ej25 and sold it again like a spa but was on to rcm for parts at the time and have got a price for brand new bottom end forged pistons uprated crankshaft and few other bits that i will probably order now next week i am starting another 94 wagon project at same time so am doing everything right its not going to be cheap but i will get one chance to do it right and have been talking to a top engine shop with regards them rebuilding my engine .The car is going to be road use but would like the option of trackday every so often not looking for massive bhp but want a reliable strong car that can be driven hard and enjoyed
Sounds like a plan Best of luck with it 
personally I’d buy a new 2.0 . Subaru short block and use your own head and stuff . Forged rods and pistons are grand but it’s nearly always the bearings that go and you can’t get forged ones of them 
.
People seem to think once you go forged your grand and it’s just not the case .
What engine shop you think of using
personally I’d buy a new 2.0 . Subaru short block and use your own head and stuff . Forged rods and pistons are grand but it’s nearly always the bearings that go and you can’t get forged ones of them . People seem to think once you go forged your grand and it’s just not the case .
What engine shop you think of using
i was hoping to go with westwardengineering in enfield i had a couple of my cars with them years ago just for little jobs , if i went with a 2.0 would i be opening a can of worms as regards the loom ?Sounds like a plan Best of luck with it
People seem to think once you go forged your grand and it’s just not the case .
What engine shop you think of using
yeah heads are good for the 2.5 so probably will go that route save some hassle i was just worried if the 2.5 is way to go thanks lads for all your adviceYou Will need different heads so will have to get 2.0 heads as you can’t put 2.5 heads on A 2.0 block . So be handier to go with your 2.5 route if your own heads are good.
