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Need help deciding a build
Posted: Sun Oct 13, 2013 5:19 am
by mx4life
I have a 93 Legacy SS with a JDM ver3 RA/STi swap in it. It has a ton of bolt ons. Last night Im sure I killed a bearing (over-rev, missed a shift) and yes it has a 08 STi oil pump in it.
Now Im looking for build options. There is alot of controversy over different short block builds 2.0, 2.2, 2.35, 2.5, stroked, not stroked. I am putting my RA 2.0 heads on what ever I decide to go with. I have the cash to build one myself or buy one already assembled. Has to have h-beam or I beam rods, nitride crank, forged pistons of course.
My goal is 375+ WHP.
Re: Need help deciding a build
Posted: Sun Oct 13, 2013 9:43 pm
by Legacy777
If that is your HP goal, I'd honestly go with the an STi long block. I know you want to keep your RA 2.0 heads, but in the long run there's more aftermarket bolt-on support on the newer motors, not to mention tuning options. I'm sure you can reach that on the older motor, but it's going to be much harder and way more money IMO.
Re: Need help deciding a build
Posted: Thu Feb 20, 2014 4:40 am
by mx4life
Bringing this up again. have definitely decided to stay with my RA/STi engine. If im going to bulid it, its going to be bad ass.
Cosworth forged pistons - $780
Keeping the stock crank / forged rods? Not sure yet
Cosworth rod/main bearing set- $180
Cosworth head gaskets- $220
ARP head bolts- $150
Cosworth Kevlar timing belt- $270
Looking to buy a stand alone management system right now. I have cash or paypal if the price is right-megasquirt, aem
If any one has links or connections for parts cheaper than this please let me know.
Re: Need help deciding a build
Posted: Mon Feb 24, 2014 1:20 am
by PhyrraM
mx4life wrote:.... stay with my RA/STi engine. .....
Cosworth forged pistons - $780 Another option is to have your builder spec custom pistons for your build. The price is likely a bit cheaper and you can specify your own compression ratio w/your own heads - .vs trying to work with a non-stock gasket thickness because your stuck with Cosworths choice on compression height
Keeping the stock crank / forged rods?....Stock crank is OK or the case can be machined (#5 thrust bearing) for a new fangled, coated, crossdrilled 2.0 crank. It cost me $300 to have my case machined for a phase 2 crank, but most seem to think that was high. Forged rods of your choosing are pretty much standard on a build like this.
Cosworth rod/main bearing set- $180 IIRC, Cosworth bearings are a re-box of somebody else. Your paying for the name.
Cosworth head gaskets- $220 I have never read about stock MLS gaskets being the primary cause of failure. Again, paying for the name?
ARP head bolts- $150 Again pretty standard for a build of this range. OEM head bolts seem to good at the 375 range too.
Cosworth Kevlar timing belt- $270 Only needed if you push your tune to the edge, where slight variations in timing can cause issues. Not needed if you tend to tune safe.
Looking to buy a stand alone management system right now. ..... Pick whatever system your tuner is cery comfortable working with. Any plug-in system meant for a '92-'96 WRX/STI (V1-V2) can be adapted easily. Stand alones are OK too, just more work - but sometimes more features per dollar too.
Re: Need help deciding a build
Posted: Thu Feb 27, 2014 4:25 am
by mx4life
PhyrraM wrote:mx4life wrote:.... stay with my RA/STi engine. .....
Cosworth forged pistons - $780
Another option is to have your builder spec custom pistons for your build. The price is likely a bit cheaper and you can specify your own compression ratio w/your own heads - .vs trying to work with a non-stock gasket thickness because your stuck with Cosworths choice on compression height I am putting the engine together myself but will have my machinist work with me on that. thinking CP pistons also.
Keeping the stock crank / forged rods?....
Stock crank is OK or the case can be machined (#5 thrust bearing) for a new fangled, coated, crossdrilled 2.0 crank. It cost me $300 to have my case machined for a phase 2 crank, but most seem to think that was high. Forged rods of your choosing are pretty much standard on a build like this.I am aiming for 375+ WHP. So my stock forged crank and stock forged rods good enough?
Cosworth rod/main bearing set- $180
IIRC, Cosworth bearings are a re-box of somebody else. Your paying for the name. Didnt kow this. You have a preference for bearings?
Cosworth head gaskets- $220
I have never read about stock MLS gaskets being the primary cause of failure. Again, paying for the name?Did some research and really liked the construction of them.
ARP head bolts- $150
Again pretty standard for a build of this range. OEM head bolts seem to good at the 375 range too. 
Of course!
Cosworth Kevlar timing belt- $270
Only needed if you push your tune to the edge, where slight variations in timing can cause issues. Not needed if you tend to tune safe.Not sure what you mean tuning safe? Im thinking of an aggresive tune so I thought this would be good.
Looking to buy a stand alone management system right now. .....
Pick whatever system your tuner is cery comfortable working with. Any plug-in system meant for a '92-'96 WRX/STI (V1-V2) can be adapted easily. Stand alones are OK too, just more work - but sometimes more features per dollar too.Going megasquirt. PRE in Portland is going to tune my car.
Re: Need help deciding a build
Posted: Thu Feb 27, 2014 9:07 am
by PhyrraM
A stock crank is fine for any reasonable horsepower level. Newer 2.0 cranks have better coatings and cross drilling, BUT not for the power - For the RPMs. Hence why Subaru only "upgraded" the 2.0 cranks. Every OEM EJ crank is forged and all have basically the same ultimate strength.
Stock EJ20G/EJ22T/EJ20K rods are forged also, but only good to the 300HP range. OEM EJ255/257 rods are also forged but of an updated design and good for more power 350ish-400ish.
Because engine bearings are supplied oil under pressure, the only difference in bearings are how the react when the oil film gets 'thin', such as on startup and under duress. Built motors don't last as long as motors with OEM tolerances, so the startup part is a wash and relatively unimportant. And if your motor is under duress - somebody hasn't done their job properly - you in maintaining it, the builder while building it, the tuner while tuning it, etc. So, an expensive or coated bearing is really more of a safety net for when things go wrong. But it's not a huge safety net, good bearing might survive a bit of detonation or low oil pressure, but will not survive anything chronic.
There are two advantages to a Kevlar timing belt. First is the longer life, however this is mitigated by the fact that higher horsepower motors need larger clearances on almost everything, and larger clearances mean the useful life of the motor is reduced from OEM. Why put a 150K mile timing belt on a 80K mile motor? Second is that the Kevlar belt is more accurate and doesn't stretch as much as the OEM belt under load and age. This makes the cam and ignition timing more accurate. The only reason for super accurate timing is a super aggressive tune - the type of tune that can cause detonation, or other problems, if the timings moved too much. Beware, this is also the type of tune that can cause problems with a slight change in gasoline composition or even a change in altitude.
Parts breed from competition sound really good on the surface. However, competition has pushed development of those parts in that direction for a specific reason. Many times that reason is reduced or doesn't exist on a street car. Hence, many 'upgrades' are just wasted money or don't have the same effect.
I'm not saying don't do it. Not at all. I'm just saying don't 'copycat' what NASIOC forum jockies spit out without doing the research for yourself, critically thinking through exactly how an 'upgrade' works, and/or talking to somebody that has seem MANY builds over time. Talking to the guy that only builds 400HP monsters (for a profit, no less) is likely to come some bias to his bottom line. Talk to a guy who does stock rebuilds with a warranty right next to a race motor designed to last all of a 100 mile race and every type of use in between. You'd be surprised how many good, professional engine builders build race motors with OEM parts and how many NASIOC readers build a street motor with 'race'parts.