forged 2.0L vs forged 2.5L options
 

Ok then here goes:

I currently have a built 2.0L with eagle rods wiseco pistons thats so far been fault proof at around 360bhp using a standard UK turbo 2000 open deck block with STI heads.

I have also acquired a closed deck 2.0L block that would need a rebore to accept the 93mm wisecos.

I am about to embark in an externally wastegated GT30R twisted turbo setup but today I have had another option present itself and one that I am very tempted by.

Basically I have been offered an EJ25 short block for £500 its done 9000 miles and is mint with no damage whatsoever.

My questions are as follows:
1: Would my current Eagle rods be ok to use in the new EJ25 block? I think they are the same size for both the 2.0L and 2.5L?
2: Am I right in thinking that the ej25 is a semi closed deck?

would this be suitable for say 500/500 with a set of wisecos slapped in?

So my options are:
1: stick with the built 2.0L that I have?
2: Build a strong 2.0L with the CDB
3: go for the EJ25 use my existing rods and buy a set of wisecos to drop in?

The car is a 1999 UK classic with STI 5 heads, apexi power FC, 740cc injectors and a 6 speed box.

Your thoughts, comments and advice most appreciated

Daz

Havent people run 500 with an open deck 2.0? I know Harvey and I think Bob R have been close to those figures

Its not just the power i'm thinking about here, its the drivability of a gt30R on a 2.5 thats tempting.

I'm pretty sure my current set up will cope but the 2.5 will be the nicer to drive i would imagine.

Daz, when you say EJ25 do you mean EJ257?

Why not use the CDB with a 79mm crank from a 2.5 + 93mm pistons = 2147cc ?

Like you say Id imagine the power band and drive of the car would be alot better on the 2.5. That turbo on a 2.0 Litre would have to have fairly late spool with a .82 housing ?The EJ257 is Semi closed but I thought the NA one was open deck. Stand to be corrected.

Would the eagle rods be reliable at 500bhp ?

Damo

Hi Andrew,

I've had a brief look at the crank case this morning and it defineatly said EJ25 on it. Its out of a Forrester Turbo i believe. Is that going to be an issue?

If I use the CDB with a 79mm crank from a 2.5 + 93mm pistons will I need to get different rods or will my current Eagle rods be OK?

Again I have thought about that option but dont really want to shell out on another set of Rods.
So if I can use my rods thats also a definite possibility.

Daz

Slight thread hijack (sorry Daz)

Is it as straight forward as that as I have a cdb in my garage that I am going to do over time, was going to use a new crank, is it just a case of having the block machined to accept the 2.5 crank? Also are the rods the same or are custom jobbies needed?
What are the advantages with this capacity over the 2.0/2.5?

Both the 25 and 257 have "25" stamped on them. Think the noticable difference between the two is the 257 has an extra breather on top of the block flywheel end.

If using a 2.5 crank to make a 2.1 then the rods are a different length than 2.0 and the pistons are different height afaik.

Any definitive answers?

At the moment I am seriously considering the 2.5 option but only if I can use my current Rods

Come on the experts among you. Somebody must have some answers to the following questions:

Can I use my current 2.0L steel rods ( Eagle rods c to c length = 5.137) to replace the stock 2.5 rods if I bought the 2.5 short motor?

If I use the 2.5 crank in the closed deck 2.0L block would I need to get different rods and pistons?

Your Eagle rods are fine for the 2.5.

Stroking the 2lt would require stroker rods and pistons.

you need to find out as has been said whether it is an EJ25 or EJ257.. if Ej25 then no.. is EJ257 then yes go for it.

Yes
yes

ej257= semi closed deck ej25= open deck.

Right then been onto the supplier of said block and it does have an additional breather. It has the normal one on the drivers side and an additional one in the middle of the block at the fly wheel end. I am therefore assuming that it's the EJ257 block.

So Im going to go for it.
Going to buy the short motor for £500 use my eagle rods and buy a set of 99mm wiseco pistons to drop into the block.

Would I be safe just dropping them in or shall I get the block honed with a clearance of three thou like my 2.0L ones were?

Anyone want to buy a OD 2.0L block, sti9 crank and a set of forged 93mm wiseco pistons for said block??

daz im just waiting for my car to be mapped as i have put a 2.5ltr closed deck block engine in mine, but all my other mods are the same ;) im hoping for 2bar of boost :D

Ok I've definatly made my mind up now.

Its only taken me two years LOL.

I'm going for the EJ257 with eagle rods and wiseco 8.5:1 pistons.
Rotated garrett GT30R with .082 housing with external 40mm wastegate

what issues am I going to have?

I thinking of having the block linered for reliability. Do I really need to do this???????
What thickness gaskets should i use? I'm thinking of standard triple steel subaru items but might go for cometics. Do the latests 2.5s still have gasket issues?
The heads will be bolted down with 11mm ARP studs
What should my boost target be? Ideally 2bar max but if thats too much i'm happy to drop off a bit????
ECU wise i'm keep the Apexi PFC but will still be running MAF
Boost control will be via AVCR.
Will have standard STI 5 heads.
Will set the limiter at 8000rpm
Running UK STI 8 Six speed (recently rebuilt)
Ideally my target is a nice useable 500/500 road car.

I feel another Dazdavies projects thread coming on :D

Any advise from the pro's out there??

Daz

i have said this to a few people and i think the rotated garret isnt as good value for money as the new MD range from lateral performance, there is a bigger turbo available other than the MD321t and another supposedly in the process as well :) for the LBs for ££££ MD is the way forward :D

i'm hoping for 2 bar of boost on mine which im expecting to be around 540bhp ish ?? but mine is a closed deck block, on a semi closed deck engine i'd say pushing/hoping for 2bar may be a short time thing ??

As Steve said,

Standard bore size is 99.50mm on the EJ257
:thumb:

The GT30R has already been purchased and is on my kitchen worktop awaiting fitment so that particular decision has been made!!


Even if its sleeved??

Hi Daz,

Just something to point out, 2.5's don't like revving to 8000 unless the cranks are worked (cross drilled). The guy in America who supplied the blocks I got said he would only rev the standard crank to 7500 rpm as above this they had an increase failure rate on the bearings.

I am using 1.3mm commetic gaskets, with the -19cc Wiseco pistons, gives overall compression around 8.0-1 with 2.0l heads.

The American companies I have spoke to claim to run upto 30 psi on standard sleeves but, again none could confirm how long for.

Hope you get it finish soon!!
Jay

anyone else with some opinions on this?

it's so cheap! eagle rods, hone to fit ej25 pistons, and you can run 450hp all day long with loads of torque and very little lag, it DOES make a fast road car.

Important IMHO to go with a freshly honed bore, and spend money on the heads so they are good for 50K+ miles. 8000rpm isn't going to happen with sti5 cams, but 7500rpm is probably worthwhile.

just my 2% of a pound

Nice one Paul, as ever I value your input.

I've just come across this again,

Daz, you are doing almost exactly what I have done, I bought a used EJ257 motor for £400 and rebuilt it (or rather Jim Litten did) with hone to fit Wiseco/Lateral pistons, Eagle rods, ACL race bearings and bolted on STi3 heads with ARP head studs, I have a 6 speed DCCD box too.

You have to be careful with Eagle rods as they have been known to have build quality issues (this isn't hearsay, I have seen and heard the problem first hand), but if yours are fine in the 2.0 then they should be OK in the 2.5.

I also have a GT3076, 0.63 A/R exhaust, 0.7 A/R compressor, TIAL 38mm WG (all sat in the garage waited to be fitted).

Andrew...

Nice one, atleast you can map your own car, even starting the fooker is gonna be a headache for me lol.

Seems we have very similar specs, although my Six speed is not the DCCD type and my GT3076 has 0.82 A/R exhaust.

I'm thinking the rods are fine as they have been used for approxiamtly 30K miles in two of my engines. The last of which was circa 360bhp

Thats if I cant sell my built 2.0L if i do sell that then i'll be buying some more rods probably going to go for Crower.

Fancy coming over to do a running in map for me?? lol

It's probably worth selling your existing short motor complete and buying new rods, speak to Lateral or RCM or Zen (in alphabetical not preferred choice order) about what's best for your application. As I said above I know 2 people, local to me, who have had issues with the little ends on Eagle rods. Mark warned me before I got mine about this but mine seem OK.

You already have 740s right? The PowerFC should start and run the car fine.

Andrew...