I have a 2.2 legacy block sat in the garage which I will be rebuilding some time in the near future , can I fit the 2.5 crank into this engine and if so what rods do you have to use ??

 

yes, you will need rods matched to pistons really.

With the ej25 crank there are various options, obvious answer at first is use 2mm shorter rods and standard pistons. However, I was told that it's better to use longer rods and special pistons, both referred to as "stroker parts". The longer rod will keep the peak pistons speeds, and the pistons will have the gudgeon pin hole further up the piston, closer to the crown to cope with the added stroke and rod length. The second method is the one used by Subaru for the pukka EJ25.

Go to www.lateralperformance.co.uk to look up company of same name, Mark there can sort you out for rods and pistons. Alternatively look in the scoobyshop for a good selection of such parts.

Paul

 

A lot of people here in the states are using the 2.2 turbo block since it is cheap and has a closed deck. The 2.5 crank will fit in perfectly from what I have been told but you will want to use the phase 1 crank I believe. 2.2L rods are fine as are 2.2 pistons I believe it ends up being 2.35L or some such. People here are using the 2.2L head gasket and WRX heads with custom pistons to raise the compression ratio back to 8.0:1 and making a lot of power.

 

You can't use an EJ25 crank in a EJ22T block, with stock rods, and pistons.

The Phase 1 EJ25 crank also has different bigend journals to the EJ20/22/25 phase 2, so regardless, they can't be used together.

Mark.

 

You will need new rods and pistons to accomodate the longer stroke crank.

Std 2.0 bore=92mm rods=130.5mm stroke=75mm
Std 2.2 bore=97mm rods=130.5mm stroke=75mm (same as 2.0)
Std 2.5 bore=100mm rods=131.5 stroke=79mm

An ej25 crank will make a 2.0 into a 2.133 and a 2.2 into a 2.33 or there abouts. A 2.0 crank in a ej25 block will make a 2.37.

The overall height (or width if on the car) of all the blocks is the same, as the inlet and exhausts are interchange able, and there isn't much space as it is. This means that the ej25 must have different piston heights to accomodate the 2mm extra strok radius (stroke/2) and 1mm extra rod length.

Some stroker kits, using non subaru cranks, use a longer stroke crank still, making 2.0l on a 92mm bore. Piston speeds will be compromised, so depending on piston type, this route won't be for everyone.

I'm only writing what I've been told, and what I've read. I would speak to Lateral Performance or SMG (in the UK) in the first instance, as they have much experience in the supply and application of the above options. I have also had good feedback and advice from Jack at iON performance in Calgary Canada. Generally of course, Cobb tuning in US, Rigoli Racing in Oz also have a wealth of experience.

Paul

 

YOur right you need to use 2.5 rods not 2.2 rods but the 2.5 crank will fit, I thought it was phase one but maybe it was the phase 2. Either way it will fit in the 2.2 block since a few people have done it here.

 

Paul, think you might be wrong about a ej20 crank in an ej22 there..

Dont you mean ej25 in ej22?

David

 

Who are SMG ?

 

EJ22 has the extra capacity purely from bore size. If you put ej25 crank into ej22 bore, you'll get 2.37ish

SMG is Stephen Guirey's company, he posts on here as SMG, and does some very interesting work. Check the "relinered 2.0 closed deck block" thread or whatever it's called in the drivetrain forum.

Paul

 

to clarify,

phase one and phase 2 differ because the thrust ebaring moved from the middle to the end.

there is nothing to stop you using a phase 1 crank in a phase 2 block, but the crank needs to be machined to accept the thrust bearing relocation.

more importantly, the big end journals on the phase 1 are 48mm whereas they are 52mm on the phase 2.

If I were doing another engine, asI have said before it would be an ej20 crank in a ej25 closed deck engine as suggested by pavlo.

2.37 litres, but with as free revving as standard and a comfrtable 8000 rpm redline! Lovely.

 

Glad we got that clear You sure ??

 

Hang on a minute adam, what happened to putting an 81mm stroke crank into the block?

To be honest, while there may be problems with the oil rings, the likes of cobb and rigolli have no apparent problems with their own engines, and those of their customers. Rigollo rev there own car to 9000.

Paul

 

Tifosi,

Where can I get a cheap closed deck 2.2 Turbo block? (Is it the block from the 22b???)

I like the idea of 2.2 block with 2.5 crank. I´d like to have more stroke than 79 mm, but I think that´s impossible. (the con rods are already very short!)

Mark.

 

Interesting thread! I can't afford to play this game with my WRX, but have done it for a number of other race applications (MB 190 E 2.5 16V anybody ).

quote from Pavlo
..... - the missing word here being "down", hence the loads on the bearings, rod, and crank will be lower, at the expense of
.....with the result that the gudgeon pin and piston crown will run hotter, so you may need to think about some big oil jets for cooling.

If you get the pleasure to look inside the homologated version of the 2.5 liter Mercedes engine you will find all of these parts lovingly designed to keep it together another 1,000 rpm above the rev limits in the standard engine. Modesty forbids me to say who persauded MB to spend the money on these as the 190E was still soundly thrashed by BMW.

Duncan

 

Yeah, missed a 'down' lol

Given the many high power engines that have used the ej25 setup I can't see a problem with piston crown temperatures. Historically, detonation on these engines (or lack of it) is very good.

I am sure the merc engine is lovely, but can we use the parts in a scoob engine? No I thought not.

Paul

 

EMS,

I think that cheap 2.2l closed deck blocks are not as common here - they are from early Legacy turbos from memory - plenty in Oz I believe. Or expensively try and get an EJ22 from a 22b - I guess they are rarer and more in demand given the number of 22b engines that have needed rebuilds.

Trout

 

Hi anyone want some 2.5 phase 1 cranks or phase 2 cranks?

 

Colin
will be in touch in the next few days , it's your fault that I got this idea