Hi All,

I'm just trying to get my head round a few things for a long term project.

I bought my 2003 WRX PPP with a knocking bottom end, and swapped the long engine for another EJ20 engine, which works fine now.

I've ended up with a spare EJ20 engine thats knocking, it wasnt knocking badly, and i dont know the exact reason why it started knocking.

Would it be OK to use the knocking engine to convert to a 2.1 stroker?

If it would be OK, what would be needed to convert it? I've seen kits that contain the pistons and little else for about £500, would that be enough to convert it?

I'm not after big power, i'm after low down power/torque with 300-340bhp

I'm sure it would be cheaper to just buy a V7 or 8 sti engine, but i'm more interested in a long term project, collecting bits as they come up (after all, thats where the fun is!) and ending up with a 2.1 engine.

As always, cheers in advance for everyone's opinions and sharing of knowledge!

 

I am doing the same and I will buying all my stuff from the states as it's alot cheaper.you will need more than 500 quid mate,you need a 2.5 crank,rods,pistons,bearings,seal kit,head gaskets,head studs,oil pump,timing kit

What heads are you planning on running?

 

Plus you will need your old block checking for size

 

It's the 2.5 crank that makes it a stroker.

 

Hi Matt,

its strange how they can sell the "2.1 stoker kit" with what looks like just the pistons?

I havent got as far as thinking of heads, i'm just trying to figure out what parts are needed for the initial conversation. Its a long term project. But now i'm wondering if it would be cheaper to get a kit? But, that wouldnt be as much fun obviously :-) My scooby is up and running, so i'm not in a rush.

So your project's back on then? I met Duncan shortly after i got the ecu, told him that someone smashed into you and could be a write off, he was gutted for you.

 

Hello mate, thats exactly what i was wondering about. Cheers for clearing that up!

So, technically, if you just swapped the crank it would be a stroker 2.1? I know it probably makes sense to refresh everything while the engines apart, but just trying to understand it all.

Cheers again

 

Your block may need the rear thrust converted depending on which block it is.

 

Read and ingest the op dude.

It's a 2003 wrx so no conversion required.

 

Doh!

In that case you wont need a centre to rear thrust conversion

 

Yeah technically if you just change the crank to a 2.5 one then it will be a 2.1.

 

Although saying that I think the reason they sell 2.1 pistons which are the same size as 2.0 is because they may have a different compression ratio for the extra throw in the crank but I'm not 100% on this.

 

std 2.0 rods/pistons will not work with a 2.5 crank or else you would have around 100:1 compression..........

crank, rods and pistons need to be "matched" to make a 2.1

i do know of at least one company suggesting you can bore a std 2.0 block massively to make a 2.1 but i would not recomend it

 

As above Resh

2.1L making stroker pistons,rods and much importantly EJ257 crank

Yes you can re-use yours WRX block if its knocking,you can buy parts easily for rebuild like ACL bearings,rods/pistons stroker combo,OE Gaskets/seals,Headgasket and ARP headstuds etc

You can go route re-using yours EJ207/205 crank and go with 2.2L stroker(I think this kit making Cosworth and few others),main difference is as above EJ207/205 crank and longer rods,pistons

Jura

 

You need these parts.

https://www.scoobynet.com/subaru-par...ged-parts.html

 

Thanks everyone!!! Have all the information i need for now! I'm going to aim for a 2.1 project to be completed for mid/late next year.

First step is to get my WRX block stripped and checked.

This is exactly why i'm so proud to be a scoobynet member.

Cheers all! :-)

 

Hi Resh

Have look on those two stroker kits

http://www.advancedautomotives.com/b...vcs-1407-p.asp

http://www.advancedautomotives.com/s...age-1484-p.asp

Those rods we run at 490bhp without the issue on the Open Deck Block and 11mm ARP headstuds,Cosworth Headgasket Kit and Cosworth pistons etc

Jura