Tidgy

doesnt always happen, but is a risk.

scoobyabs

iTrader: (4)

In years gone buy when big build Impreza’s were being built on on a regular basis.

Many people had CDB’S fitted with Darton sleeves. Some of these blocks had head gaskets problems.

when the engine were stripped down it was found that the new sleeves had settled and then dropped.

This required the block half’s to be decked again and the engine rebuilt.

Outfront Motorsports in the States used to fit Darton Sleeves to there blocks. The sleeves always dropped, they tried many things but nothing stopped the sleeves from dropping. They no longer offer this service.

Because of the risk that sleeves may drop and the costs involved, many people are reluctant to have sleeves fitted to there block.

Alyn you have a very good reputation and people find you very helpful. Hence so many people recommend you.

Do you guarantee that the sleeves will not drop on blocks you have carried out the sleeve job on.

stockcar

can you guarantee you will be able to get out of bed tomorrow morning?? or that the no.19 bus will turn up??

no such thing as 100% guarantee if your talking about extreme HP / race motors BUT we have undertaken this process for many years (mainly for people at the extremes of m/sport because of the costs involved to do it correctly) and we have had no comebacks.......
I can't comment on other companies or people who have not had success as not party to what they have done but we don't just do Subaru machine work and have plenty of examples across many manufacturers (Focus RS / Volvo T5 5pot being just one type)


just to add we rarely use Darton sleeves so unlikely the blocks you mention were anything to do with us but can and do if needs be

stockcar

managed to find some older pix so have added them to our FB page to try and show the liner thickness issue with 2.5's and also the new casting machining flaw with 'thick walled' EJ20 blocks

scoobyabs

iTrader: (4)

Alyn I have never read any thing bad about your work. You probably are the most recommended person for parts, machine work, engine building.

In NO way was I implying that blocks you have replaced the sleeves on have dropped.

Vxr2010

Just my long 2 pence worth , i think as it stands the 2.5 is a good engine with a bit of a fault (lol originating from subaru design ) but can be much improved when it’s forged , im sure not all 2.5 have failed it would be interesting to know the whole picture of failure v still running fine , my Fsti engines have failed over time , bit of a bill then a sorted engine , my concern when i took mine to get repaired was the cosworth cs400 with a split liner at the top ,it was a standard cs400 , Cosworth build a pretty good engine , i just think being realistic with the power levels is important , the more you ask from an engine you may as well do a graph showing reliability going down hill , but that applies to any car lamborghini or ferrrari included , i know the performance Audi’s tend to have problems too , the us claims , they probably use the same parts as the uk so i can’t see it being any better reliability wise , i think some ask too much from an engine , if it’s a drag car and you do lots of engine mods plus have a big budget expect engine issues , i run v8 with 500 bhp rwd in the wet i don’t want more power lol , again how much power the more you put in the old reliability graph goes down as you get to the limit of what the engine can do even with mods , so say a bit under 400 ish or so plus, on a scooby 2.5 you are getting into territory of it going wrong even with mods , mine are daily drives so i don’t want big bills all the time , big power even with 4 wheel drive must get to a point of hard work to drive ?

BrownPantsRacing

iTrader: (6)

Interesting pics thanks for sharing.

Makes you realise just how thin the standard liners are.

Kaosone

2.5 block ****

Kaosone

Slightly off topic but another question: What was the magic formula build from say 15 years ago?

The EJ25 hasn’t hit the streets yet, so no low down torque or 2.1 strokers. So taking the 2.2L out of the equation did people just fit big turbo’s to 2.0L’s & accept the lag?

LewisScoob

iTrader: (5)

There was methanol and I’m sure there were aftermarket 2.1 kits, just not with the now commonly used 2.5 crank.

domino46

proper 2.5 engine **** lol

https://www.iagperformance.com/IAG-W...g-eng-1611.htm

Apostle

I understand that from an engineering point of the view - the 2.35 stroker combination is the PERFECT stroke and bore size together.


Thus it’s the best base for big power builds, that as a rotating mass it is the best you can get from Subaru engines.

I did have a well built 2.5 which made 460/480 ‘ish @ 1.65bar It was a fragile torque monster that lasted 43k until it spun a rod bearing

I was advised to get a 2.2 block and convert / swap it all across for a princely sum. Made 480/460 ‘ish @ 1.65 bar.

Hopefully now indestructible. Turbo is a Blouch Dominator Xtr2.5 with a Grimmspeed tmi 😃


FWIW my limited advice is that 400 is probably safe for a 2.5. If you really want more build a 2.1 ✅ or find a 2.2 block and go that way (find one is the states and crate it over for a fair price).

Kaosone

If a 2.2L & 79mm crank offers the perfect bore / stroke configuration, then it sounds like another vote for sleeving down 2.5L cylinders

Thicker sleeves in a 2.5 would increase the wall thickness, improving strength (combined with closed decking). As well as being readily available.

Has this ever been done?

R666ORY+1

Post 59 in this thread goes over that mate.

Henrik

iTrader: (5)

Hmm, I think #59 is referring to something else, namely an ej25 block on standard bores, but with the 75mm crank of the ej20.

Kaosone means an ej25 block eith it's 99.25(?) bore sleeved to 96.5(?) mm. This would give it 2.2 litres with an ej20 crank, or 2.3x with a ej25 crank, but thicker cylinder linings.


​​​​​

stockcar

have sleeved plenty of blocks in all directions over the years.............

and yes as already mentioned "de-stroking" a 2.5 is not the same it simply achieves a similar capacity

Kaosone

What would be the cost of sleeving the cylinders of a 2.5 block down to whatever the bore diameter of 2.2L Alyn?

Cheers

Henrik

iTrader: (5)

​​​​​​In your professional opinion, would you say a sleeved ej25 (to ej22 capacity) would be the "strongest" commonly available Subaru block, or would an ej22 still be the one to go for (to achieve a 2.3x)?



​​​​​​

R666ORY+1

Can I dare confuse things more (sorry). What about the engines in the SVX and TriBeca? Are they no good to start with? You can actually pick up both if you shop around for less than a 2.2 block. Ok agro but you could still claw back some cash merely by breaking. I’m guessing I am way of the mark as am sure I’ve not just had a eureka moment. Also I don’t claim to know it all (far from). Are these engines not suitable or simply not cost affective to build in the bigger picture? I know Andy F is/has run a few 3.3 and other. Just a thought!

stockcar

2x totally different engines...............

the (rare) 6cylibder 3.3 EG33 SVX engine is essentially an EJ22 with an extra set of cylinders on the front nose that with the right components can ve stroked to circa 3.6 and run in excess of 1200hp............quite bulky due to the extra pair of cylinders

the Tribeca EZ30 3.0 and EZ36 3.6 H6 engines are a totally different design, much more compact but no where remotely as strong in std form as the SVX engine...and ultimately don't appear as tuneable as above

Kaosone

I just want to know if you can take a widely available EJ25 crankcase, sleeve it down to 2.2 & closed deck it to build up a 2.35.

Hopefully this works out more cost effective than sourcing an EJ22 crankcase.

Maybe it wont be as strong as an actual EJ22 but It would be stronger than a EJ25 & what is allegedly the ideal configuration.

adam.pah

There's a guy in Oz running an H6 conversion and posting some crazy times at the strip. Not sure which exact engine he is running but it must be mega power. Insta: 30pnd.
He also has an EJ25 that runs 9 second quarters.

stockcar

if that question was aimed at us then apologies that we missed it but your far better getting in touch and discussing your options "one to one"...........we get far too busy to see or fully read every forum / thread....

in general terms then yes a 'sleeved' 2.5 block even at original capacity makes a very high performing and capable engine and can be made any size option you require

R666ORY+1

I did not word that very well. I am (semi) aware of the differences between 2.2 v 3.3. I meant price wise is it becoming more cost affective to go down the 3.3 block route rather than the premium being sort for a 2.2 block. Was more curious if that cross over point (financially) is close or a million miles apart. I have no real knowledge of the TriBeca engine so thank you for educating me. The addition of the electric motor driven/assisted “e turbo” really interests me. I have often wondered about similar (started thinking about these things personally over 20 years ago). With energy harvesting via braking becoming more and more common place trickle down technology will in time mean these systems will be common place and could well be a retro fit mod we can all carry out. Yes I understand the ICE could be on its last knees but no one can truly predict the future. At what point do engine builders and mappers embrace emerging tech And start factoring it in to their services? Or am I naive to the fact they are all ready doing so but don’t shout about it for fear of losing the potential competitive edge over others. Someone somewhere must be thinking of it if I started 20 years ago.

Kaosone

Just got off the phone with Alyn...

If you supply him an EJ25 crankcase, he’ll supply the sleeves, machine the block & fit them for around £1450 (give or take depending on sizes etc).

Closed deck inserts are a further £480 (all prices include VAT).

So a closed deck & sleeved 2.2L block can be built for around £1930.


Even if you had to buy a used EJ25 crankcase (which start @ £300 on eBay) it’s still probably cheaper than buying an EJ22 block (depending if the only one currently on eBay is anything to go by).

Also an EJ22 block would then need machining for the rear thrust conversion to take the EJ257 crankshaft, at a cost of around £400 (I think). I’d assume being a used engine the cylinders would need honing too .

Then because racecar; machining for 14mm head studs is £130 (or £135) & the 14mm stud kit is £399.


Alyn also mentioned that the bellhousing on the EJ22 is only 4 bolts which can have an issue with flex, especially with sequential gearboxes & the later cases are stronger. He also said he has some sleeved engines running over 800BHP

So there, the 2.35 can live on without the EJ22 block & possibly be stronger & cheaper too (maybe).

Henrik

iTrader: (5)

also the nice thing with the new liners is that presumably they'd be std size, which means that you could rebuild the engine a couple of times and go bigger pistons each time if required, where-as a standard ej22 would probably need a +0.25mm piston immediately, so in theory fewer rebuilds possible

stockcar

bearing in mind EG33 blocks were only ever fitted to the fairly rare SVX then if anything it would cost at least as much to build a 6pot from this base, notwithstanding the fact you need 1.5 times rods / pistons and if you go billet 'stroker' crank then its $$$$$$

the far more common (but totally different) EZ30 / EZ36 engines are relatively cheap in comparison but nowhere near as tuneable in std form

bear in mind that all require a reasonable amount of work to package into a bay that was intended for a 4pot set-up

stockcar

rear thrust conversion is far less than 400 but the old blocks may require a line bore to true them adding extra work / bills

Kaosone

Possibly then the £400 value was the approximate cost of the machine work an EJ22 block would need no make it usable.

IainMilford

iTrader: (15)

If you find a 22b block they are already rear thrust converted but pretty rare !