EJ257 BUILD HELP

just bought a std ej257 sti short, was gonna leave it std and uprate most things round it. puttin a AFP td05 20g on it.
but heard the pistons aren't up to much, are there any drop in ones? and how much power can the std rods take?
i'm now getting tempted to get the MD321T as i've heard rave revues.
any help would be great.

On the standard rods I would not push it more than 1.3 bar of boost and 380 of each for reliability purposes.

Mark @ Lateral Performance does a set of drop in wiseco pistons that should be ideal for a 20G. Best speak to Mark and he will take you through all the options.

Banny

Pistons would be a good idea, rods will be fine at that level.

Bores would need honing even with drop in pistons - the Wiseco's normally run about 0.003" piston/bore clearance.

Mick

Originally Posted by banny sti

On the standard rods I would not push it more than 1.3 bar of boost and 380 of each for reliability purposes.

Mark @ Lateral Performance does a set of drop in wiseco pistons that should be ideal for a 20G. Best speak to Mark and he will take you through all the options.

Banny

Standard rods will take alot more punishment than that as long as you don't rev past 7000 rpm. IIRC Andy forest ran his standard EJ257 with drop in pistons to 2.4 Bar 570 lb/ft just for the fun of it.

Originally Posted by merlin24

Bores would need honing even with drop in pistons - the Wiseco's normally run about 0.003" piston/bore clearance.

Mick

The drop ins are A and B graded to match the pistons that come out, so no honing required, although i do have doubts over the precision and possible descrepencies between bores on the EJ257 to say that drop ins may not be the best choice.

If you choose to split the block, to change the rods, then i would go for hone to fit pistons and get a good machine shop to do the honing to correct clearances for each piston.

Was running a TD05/06 20G on my built 2.5 and felt it was great, very fast road car, until the MD321T went on and holy moly!! Still not running the 321 to full potential (currently at around 430bhp) but the pull to the red line is relentless.

Built 2.5 MD321T+ , 100 octane fuel, 1.7 bar, ZEN map = 470/470.

Get it done now. Great turbo and engine combo.

And budget for either a 6 speed or PPG box with a decent clutch to handle that power!

What mods do you have on your Type R as it stands?

been speaking to chy at penine subaru and he's reccomending there 2.5 closed deck but i don't think i can justify the extra cost.
i've got a helix paddle clutch to go on the car and looking at either the ppg or quaife or 6 speed box. brembo's all round.
i've ordered 740 cc injectors gt spec 2 headers, got a 3" straight through, and keeping for the time being the sti 8 tmic as i don't wanna hack the car up. going for a simtec ecu as well.
probably missed loads out but i'm sure you guys will be asking.

My bug is currently getting a new ej257 short fitted.

The standard piston/rods were binned straight away in preference for eagle billet rods/AP forged/coated pistons because the builder (Perfourmance motorsports) has seen bent ej257 rods when hitting only 200kw atw (265bhp atw).

Personally, I'm looking for around 320 bhp atw and I'm spending enough dough on the engine now without having to have the thing ripped out again in a few months! The upgrade to billet rods/forged piston costs the same as taking the engine out............it's a no-brainer!

Even if your current mods keep you on the safe side of 265bhp atw you should think about future turbo/fuelling upgrades. Better to get the work done now whilst the engine is out.

If you do decide to stick with the standard rods/pistons, I've got a brand new set here looking for a new home if yours go pop

Good luck

search for darton sleeves, will hold 2 bar easy.

https://www.horsepowerparts.com/inde...product_id=223