BrownPantsRacing

iTrader: (6)

Generally yes, these days it's cheaper to buy a brand new genuine Subaru crank than it is to get one re-ground to suit some oversized shells. Also, with a re-bored 2.5 block the cylinder walls are thinner than standard and have known to crack at 450bhp, so I would be doing CDB inserts as you've said or buying new blocks halves if you don't want to go CDB. Realistically, for the minimal cost a CDB conversion is by far the best way forward.

So a typical spec would be:
Re-machined block halves centre bored if required and re-faced with CDB inserts.
New genuine Subaru crank
Forged rods (Manley or something similar)
Forged pistons (Mahle, JE, cosworth etc and there are different grades of forged pistons depending on final goal and use)
Cosworth or RCM head gaskets
ARP or RCM head studs (uprated 11mm probably enough, only need 14mm when chasing high power)
Genuine Subaru full seal and gasket set
New genuine subaru water pump or uprated pump
New genuine oil pump or uprated pump
New timing belt kit
Coolant, oil, other gaskets & labour.

Realistically that lot will set you back over £5k from a reputable builder.

If you're increasing the power then you'll also need:
Uprated fuel pump (Walbro, RCM, SWRD)
Uprated injectors (Either re-flowed or new Injector Dynamics units)
Fuel pressure regulator
3" downpipe and exhaust
CAI setup
Decent turbo depending on power goals
4 bar map sensor depending on power and boost target
3 port boost solenoid
FMIC setup or uprated TMIC setup

Sure there are bits I've forgotten.

the shreksta

iTrader: (20)

Add in an uprated clutch/brakes/suspension and fast road set up and decent rubber all round, no point upping the power if the chassis cant handle it.

BrownPantsRacing

iTrader: (6)

Yes 100%.

Was going to mention that but I'd already brain farted too much on the thread by then!

the shreksta

iTrader: (20)

Lol

4evascoob

🙄

Already doing injectors and Caik, already has 3" fill system and decat, fuel pump is fine and as for brakes yes maybe new pads but that's it it's mot going to be tracked. Also for anyone that has driven a new one the handling need leaving well alone, stock is absolutely fine I believe it is slightly wider than anything pre 2014 but I stand to be corrected.

Rusti

iTrader: (4)

If youre looking at 400+ then a fuel pump change to a higher flow is recommended, especially as youre already going to up rate the injectors

4evascoob

Thanks rusti 👍

rob84

iTrader: (5)

I'd always recommend Paul Finch aka MotorsGT or Alyn at ASP on here for block work.
The liners don't get changed only bored out so any ovality is no longer present & to a specific clearance for the pistons to expand. And must be done with a deck plate attached to prefect any imperfections. top of the Block halves Decked and an insert fitted in around the tops of the bores. Like I mentioned earlier this prevents or tries to prevent the liners from cracking. No such thing as a generic kit is all individual to the block you supply. I went pistons at a 2618 compound H-Beam con rods. Mahle big end shells and ACL main shells, Modified & deburred PRV valve in the oil pump. STD STI Crank sis very useable at quite high power outputs. Cosworth multi layer headgaskets. High tensile head stud kit. or if budget allows go 14mm studs.

Air pump delete
High flow fuel pump
Bigger injectors
FPR
Cold air intake
FMIC optional
Remap to suit