Best Value Light Rebuilt Engine Formulae

Posts specific to the 2.5 litre turbo engine

Best Value Light Rebuilt Engine Formulae

Postby bigBADbenny » Tue Aug 13, 2013 1:29 pm

It seems its a matter of time before an engine rebuild or refresh is required with the 2.5T.
I've begun research in the Built Motor Discussion Thread on Nasioc, so if and when the time comes, I'm prepared with solutions for maximizing my funds and hopefully DIY skills regarding my motor makeover.

From what I've learned so far the value equation comes:
First from slightly over speccing the intended power level and then tuning it to run at a lower power level. I'd build for C 300 atw and run at 200-250 atw.
Secondly from using a mix of OEM and aftermarket parts and mostly OEM clearances.
Thirdly from supporting the engine completely with monitoring, failsafes and a good tune.
Of particular interest to me is per cylinder tuning, either 4 channel EGT or AFR. Overkill? You bet and I love it :)

So let us know your opinion, what you're planning, what you'd do again.
Mostly interested in a slightly more powerful than stock output engine that will run reliably for 100K+ klm, and the most affordable, creative and commonsense approaches to that outcome.
User avatar
bigBADbenny
 
Posts: 10420
Joined: Tue Oct 04, 2011 6:36 pm
Location: Collingwood, Melbourne
Car: MY07 GT-B 6MT OBP Wagon
Real name: Ben Richards
Profile URL: http://tinyurl.com/agvbzop

Re: Best Value Light Rebuilt Engine Formulae

Postby bigBADbenny » Tue Aug 13, 2013 1:29 pm

Reserved :)
User avatar
bigBADbenny
 
Posts: 10420
Joined: Tue Oct 04, 2011 6:36 pm
Location: Collingwood, Melbourne
Car: MY07 GT-B 6MT OBP Wagon
Real name: Ben Richards
Profile URL: http://tinyurl.com/agvbzop

Re: Best Value Light Rebuilt Engine Formulae

Postby dr20t » Tue Aug 13, 2013 2:48 pm

Great thread Benny

This is going to sound flippant - but it really is not and I'm dead serious

Used but good condition, low km (sub 40,000 kms) JDM Version 8-10 EJ207 or newer FA20 will always be my pick over a fully built motor if only going for up to 280wkw

Reason is the ej255/257 even when fully built, are inferior in their clearances and tolerances to a factory engine of the above variants.

The problem with EJ / boxer configuration is the horizontally opposed nature- which means a proper torque plate needs to be used to ensure accurate machine work. Also, the piston to bore clearance and bearing clearances are seldom setup correctly unless a blueprinting exercise is completed which puts a proper rebuild outside most people's budgets.

And finally, quench area and head port design is rubbish on any 2.5 turbo variant. They are prone to detonation and even with upgraded forged pistons, the longer stroke in the same cylinder dimensions as a 2.0 litre means gudgeon pin in the piston is higher up, so the piston skirt is skinner and shorter which affects ability to rev freely and also the power handling capability of the piston longer term.

Proof of this is the timing map for a jdm ej207 compared to a ej257 or 255. Have a look at the difference and tell me your thoughts.

For the money, I would try to shoe in a proper EJ or FA motor not an audm or usdm variant.

Mick
Addicted to corn juice....

My FrankenStien build thread here: viewtopic.php?t=14137
User avatar
dr20t
 
Posts: 4191
Joined: Sun Oct 23, 2011 10:43 pm
Location: South West Sydney NSW
Car: 04 Liberty GT Auto
Real name: Mick
Profile URL: viewtopic.php?t=14137

Re: Best Value Light Rebuilt Engine Formulae

Postby bigBADbenny » Tue Aug 13, 2013 3:19 pm

Indeed this or something similar was mentioned in one of the Nasioc threads.
I've seen your references too. It's definitely an option we should explore and list.

Let start with some derpy n00b Q's:
Where best to research these engines? (I'll be compiling your references on this forum)
Is this a factory closed deck block or was that V6 & V7?
If swapped in, what ECU or piggyback is preferred?
User avatar
bigBADbenny
 
Posts: 10420
Joined: Tue Oct 04, 2011 6:36 pm
Location: Collingwood, Melbourne
Car: MY07 GT-B 6MT OBP Wagon
Real name: Ben Richards
Profile URL: http://tinyurl.com/agvbzop

Re: Best Value Light Rebuilt Engine Formulae

Postby bigBADbenny » Tue Aug 13, 2013 3:23 pm

dr20t wrote:And finally, quench area and head port design is rubbish on any 2.5 turbo variant.

Does this have anything to do with the popularity of 2.3L destroked 2.5's?

Another area of research is using SOHC heads for better reliability over the complexity of DOHC & AVCS.
User avatar
bigBADbenny
 
Posts: 10420
Joined: Tue Oct 04, 2011 6:36 pm
Location: Collingwood, Melbourne
Car: MY07 GT-B 6MT OBP Wagon
Real name: Ben Richards
Profile URL: http://tinyurl.com/agvbzop

Re: Best Value Light Rebuilt Engine Formulae

Postby Robbks » Tue Aug 13, 2013 3:30 pm

there's a huge thread on RSLC http://www.rslibertyclub.org/forums/sho ... ion-thread
talking 2.2, 2.35, and 2.5 builds.

Brent's thread here http://www.rslibertyclub.org/forums/sho ... difference
may also have some useful info (400+ KW ATW from a 2.4..? )

or forget the 4 bangers and build a Turbo'd EZ30.
viewtopic.php?f=16&t=21509
coyote wrote:Sure, a GTR is fast ... but it's about as interesting as listening to grass grow.
User avatar
Robbks
 
Posts: 2185
Joined: Wed Jan 05, 2011 8:21 am
Location: Hobart, Tas
Car: MY06 3.0RB Wagon
Real name: Rob
Profile URL: viewtopic.php?f=10&t=12350

Re: Best Value Light Rebuilt Engine Formulae

Postby bigBADbenny » Tue Aug 13, 2013 3:47 pm

Good stuff! I'm sure we can reveal a few good options, with suggested parts, for those in need.
User avatar
bigBADbenny
 
Posts: 10420
Joined: Tue Oct 04, 2011 6:36 pm
Location: Collingwood, Melbourne
Car: MY07 GT-B 6MT OBP Wagon
Real name: Ben Richards
Profile URL: http://tinyurl.com/agvbzop

Re: Best Value Light Rebuilt Engine Formulae

Postby dr20t » Tue Aug 13, 2013 4:16 pm

Robbks wrote:there's a huge thread on RSLC http://www.rslibertyclub.org/forums/sho ... ion-thread
talking 2.2, 2.35, and 2.5 builds.

Brent's thread here http://www.rslibertyclub.org/forums/sho ... difference
may also have some useful info (400+ KW ATW from a 2.4..? )

or forget the 4 bangers and build a Turbo'd EZ30.
viewtopic.php?f=16&t=21509



Rob - the above are ok builds I guess (the Brent build has some questionable parts choices).

But my point is factory reliability for the Subaru 'performance' variants are better than built options up to a certain limit.

I would only trust a handful of engine builders in the country with an all out EJ motor. Robyn from PMS, Serge La Monaca, tony knight or more recently, Leigh bird from deshele.

However unless you are going into an all out blueprinted motor, and willing to spend over 20k on long block alone, then I would go with a jdm ej207 or fa20 anyday of the week


bigBADbenny wrote:Indeed this or something similar was mentioned in one of the Nasioc threads.
I've seen your references too. It's definitely an option we should explore and list.

Let start with some derpy n00b Q's:
Where best to research these engines? (I'll be compiling your references on this forum)
Is this a factory closed deck block or was that V6 & V7?
If swapped in, what ECU or piggyback is preferred?


The 2.2/2.4 builds are awesome when done right. But you're talking big bucks here. Not a small rebuild with some performance add ons.

A proper setup of that build would go:

Semi closed or full closed deck block $500 second hand
Forged custom skirted pistons to suit stroker - $1000
Forged pauter or better rods with arp L19 rod bolts - $800
Forged crank - $800
Wet ductile iron sleeves $800
Machine work (acid dip, sleeve fusing and alignment, torque plate hone, dowelling etc) $2000
King / ACL race bearings $200
Arp case bolts $500
Upgraded oil pump $500
Sump and baffles $500
Oil pickup $200
Balance rotating assembly - $300
Blueprinting and assembly of short block- $1500-2000
Arp L19 or better head studs $400
Cosworth or cometic headgaskets $250
Head work - $1500-5000 depending on level of port work
Cams $1200-1500
Valve springs and retainers $500
Gasket / seal kit $500
Timing kit with gates racing belt or better $500

Total : $15,500 to $20,000 depending on porting, blueprinting and who you know

Plus labour to remove and refit, ancillaries like turbo, intercooling, exhaust, fuel system, lubrication and miscellaneous hoses and fitings etc - easy $8000 with all that

Clutch for 6 speed $1500-2000 or built auto $4000

Upgraded front and rear diffs $1000- $1500

That's with stock ecu - if you need aftermarket you need minimum haltech so another $2500 plus fitting and tuning (another $1500). More for a vipec or autronic or motec (say $5k for those fitted)

Now you're getting into ridiculous territory

That's almost $40k above

Sure you could skimp out and buy cheaper components or not get porting done or not have it blueprinted but that's when it becomes only as reliable as a stock factory 'performance' motor like a ej207 or fa20 like my original suggestion


bigBADbenny wrote:
dr20t wrote:And finally, quench area and head port design is rubbish on any 2.5 turbo variant.

Does this have anything to do with the popularity of 2.3L destroked 2.5's?

Another area of research is using SOHC heads for better reliability over the complexity of DOHC & AVCS.


I would never go back to sohc unless its a straight drag car where you're at wot in high rpm all the time

Quench area has partly to do with the reason for stroker builds yes. From speaking to Robin - he loves the 2.2/2.3 builds - and he knows his shit more than me or anyone else on this forum so I would listen ;)

But again it comes down to budget.

With advances in fueling (e85 fuel, injector dynamics awesome injectors, better stock location fuel pumps), turbo technology (billet wheels, ball bearing, hybrid setups with mix n match housings and wheel combos); and massive improvements in tuning capabilities, modern (good, ie non ej255) 4 cyl turbo engines can easily make close to 300kw atw without too much internal work.

So budget conscious I would stick to my reccomendation above

Mick
Addicted to corn juice....

My FrankenStien build thread here: viewtopic.php?t=14137
User avatar
dr20t
 
Posts: 4191
Joined: Sun Oct 23, 2011 10:43 pm
Location: South West Sydney NSW
Car: 04 Liberty GT Auto
Real name: Mick
Profile URL: viewtopic.php?t=14137

Re: Best Value Light Rebuilt Engine Formulae

Postby <GB> » Tue Aug 13, 2013 4:33 pm

I wouldn't put a 2l engine in a car fitted with a 2.5 if you plan on limiting who youre selling it too or going all out, I would want the engine that came out of the car tbh all numbers match ect

also the 2l bit too laggy for most people day to day from the ones ive driven.

better off selling and buying a v8 or get an evo
<GB>
 
Posts: 2290
Joined: Tue Nov 22, 2011 9:05 am
Location: MELBOURNE
Car: 08 Liberty STI
Profile URL: viewtopic.php?f=18&t=14660

Re: Best Value Light Rebuilt Engine Formulae

Postby bass_straitener » Tue Aug 13, 2013 4:47 pm

<GB> wrote:I wouldn't put a 2l engine in a car fitted with a 2.5 if you plan on limiting who youre selling it too or going all out, I would want the engine that came out of the car tbh all numbers match ect

also the 2l bit too laggy for most people day to day from the ones ive driven.

better off selling and buying a v8 or get an evo



Agree with what GB is saying.
"If A is a success in life, then A equals x plus y plus z. Work is x; y is play; and z is keeping your mouth shut."
User avatar
bass_straitener
-stickered-
 
Posts: 2247
Joined: Mon Jul 25, 2011 8:31 pm
Location: Melbourne, Victoria
Car: MY12 C63
Real name: Bruce
Profile URL: viewtopic.php?f=10&t=14781

Re: Best Value Light Rebuilt Engine Formulae

Postby dr20t » Tue Aug 13, 2013 4:57 pm

<GB> wrote:I wouldn't put a 2l engine in a car fitted with a 2.5 if you plan on limiting who youre selling it too or going all out, I would want the engine that came out of the car tbh all numbers match ect

also the 2l bit too laggy for most people day to day from the ones ive driven.

better off selling and buying a v8 or get an evo


Agree about the V8 or Evo however disagree on the torque

Jdm ej207 makes more torque that the ej257
Addicted to corn juice....

My FrankenStien build thread here: viewtopic.php?t=14137
User avatar
dr20t
 
Posts: 4191
Joined: Sun Oct 23, 2011 10:43 pm
Location: South West Sydney NSW
Car: 04 Liberty GT Auto
Real name: Mick
Profile URL: viewtopic.php?t=14137

Re: Best Value Light Rebuilt Engine Formulae

Postby <GB> » Tue Aug 13, 2013 5:12 pm

dr20t wrote:
<GB> wrote:I wouldn't put a 2l engine in a car fitted with a 2.5 if you plan on limiting who youre selling it too or going all out, I would want the engine that came out of the car tbh all numbers match ect

also the 2l bit too laggy for most people day to day from the ones ive driven.

better off selling and buying a v8 or get an evo



Jdm ej207 makes more torque that the ej257

you talking in the normal range of most day to day driving? 1500-3500rpm?

got to be realistic here you might find a good jdm engine but then again you might not... why not build your own engine to handle under 300awkw and call it a day? I just cant see many people buying a jdm engine for these best build situations, people like the fact they have a new rebuilt engine! probably comes with some form of warranty too, do these jdm engine come with that?
<GB>
 
Posts: 2290
Joined: Tue Nov 22, 2011 9:05 am
Location: MELBOURNE
Car: 08 Liberty STI
Profile URL: viewtopic.php?f=18&t=14660

Re: Best Value Light Rebuilt Engine Formulae

Postby dr20t » Tue Aug 13, 2013 5:28 pm

Yeah that's what I meant when I said if you're chasing big power then it has to be built

You're spot on about it being hit and miss

All I was saying is a "mildly" built ej255 or 257 is just the same reliability as a stock ej207, so its not worth it in my opinion

If you're chasing 300 atw or over, then definitely built motor is required for longevity.

I'm going for 330-340 atw on my stock jdm ej207 - but I don't mind if it doesn't last more than 20,000kms. Because if it goes after that then that's when I'll throw in custom forged pistons, pauter rods, balance it all and blueprint so it revs to 9500rpm (not 8800 like at the moment), stock w20 heads with a clean up, 280 degree quad avcs cams, new gasket kit, precision 6466 rotated, and make 400kw atw reliably on e85.

But that's me - my point is that for 250kw atw I wouldn't bother doing a half assed build. Most entry level forged pistons and rods are worse than factory ones. Crank is ok.


Edit - here are some links worth reading :

http://forums.nasioc.com/forums/showthr ... ight=ej207

Mick
Addicted to corn juice....

My FrankenStien build thread here: viewtopic.php?t=14137
User avatar
dr20t
 
Posts: 4191
Joined: Sun Oct 23, 2011 10:43 pm
Location: South West Sydney NSW
Car: 04 Liberty GT Auto
Real name: Mick
Profile URL: viewtopic.php?t=14137

Re: Best Value Light Rebuilt Engine Formulae

Postby bigBADbenny » Tue Aug 13, 2013 6:06 pm

Great info: may we please focus on Best Value?

Looking to go semi built for mid range power levels with as much DIY as possible to end up with:
a better value proposition than a simple rebuild with stock parts or a drop in replacement motor.

Not max power, not max boost, not high revs, not drag or TA, just adequate power for street with reliability ;)
User avatar
bigBADbenny
 
Posts: 10420
Joined: Tue Oct 04, 2011 6:36 pm
Location: Collingwood, Melbourne
Car: MY07 GT-B 6MT OBP Wagon
Real name: Ben Richards
Profile URL: http://tinyurl.com/agvbzop

Re: Best Value Light Rebuilt Engine Formulae

Postby coyote » Tue Aug 13, 2013 6:15 pm

Ben, best value by far is a new factory 2.5 short motor fresh from the crate.

Do a few minor mods, keep it around 220atw and it'll last for ages.
Image

** Team Tony **
User avatar
coyote
 
Posts: 2207
Joined: Mon Jul 30, 2007 2:33 pm
Location: brisbane.qld.au

Next

Return to 2.5T engine specific

Who is online

Users browsing this forum: No registered users and 9 guests