Hi all, I've owned my forester for about 4 months now and its good, i love it but there's a bit of piston slap on start up until it gets warm. It's done it since I owned it and hasn't really got any worse, I change the oil every 5/6k but I want to rebuild it for reliability or buy a new motor. same spec, with no mods or upgrades as im happy with the power/economy.

 

its an EJ20G.

 

Anyone know if this firm is ok to buy an engine from?

 

http://www.ebay.co.uk/itm/Subaru-Impreza-JDM-WRX-STI-EJ20-207-Forged-Pistons-Rally-Stage-Upgrade-Pro-Set-/380934443151?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item58b176508f

 

 

 

ideally you will want 92.5mm pistons so your bore can be sized/honed to suitable clearance for usage.

Fast road use with forged pistons require less clearance than an engine dedicated for track use.

Personally I prefer CP pistons for more road usage build as they can run quiet & bore clearance range is very good.

Would be good to strip & review your engine prior to getting parts as if found other defects it would be easy/cheaper to go for another engine over rebuild perhaps ...

Great info cheers, I'll look into it thanks mrB

Can anyone recommend a decent jap breaker firm to get a low mileage engine from?

the problem your going to have with getting an engine from a breakers is, why is it in there in the first place, you dont know the condition till its too late, dont cut corners and replace it all yourself and then it will last well over into the 100k, ive just had to bite the bullet with mine and now it outperforms similar cars. its worth refreshing yours mate.

That's true, I thought it was odd that so many 15 year old cars have such low mileage. What pays do I replace though? New pistons or new rings and bearings? Cheers all

If you buy used from specialist engine importers who deal with recycled engines from low mileage JDM you can do ok.

Rebuild could be a disaster if you have no experience.

certainly sounds as if needs new set of pistons & rebore, If big end & main bearings are perfect you would not need replace but all needs good inspection by someone who has experience. you will replace all engine seals/gaskets & Heads should be stripped, cleaned, valves checked/lapped etc.

A decent helpful machine shop will make things easier for you but still plenty of areas in the rebuild that many first timers can mess up.

Did you try api ? They import engines as well as doing in house rebuilds.

Jdm engines cover less miles in there lifetimes due to the fact that public transport in japan is superior and nearly everyone uses it, cars are mainly weekend use,

If I'm correct in certain areas you have to have somewhere to keep the car before you own one due to space being limited and at a premium. The leases only last for x amount of years as well

Hi all, cheers for the infos, I reached api, they say :

A rebuild of your unit is going to cost £1800.00 + VAT [ £2160.00 inc ] as an engine only rather than a car. The build includes:

Crank

Competition bearings

Modded oil pump

Rebore & New pistons - oversize

Heads rebuilt

STi Gaskets and seals

Cam belt

All parts chemically cleaned.

It's more than I can afford, and by the time I get the engine out I might as well do the work myself, machine work aside. Good news is that it passed mot yesterday with no advisories!

Whoop good news on the mot, what kind of exhaust do you have on ? it does seem about right for a proper build but, you may not even need a new crank. And like you say if funds aren't available not feasible. How good are you with a set of spanners ?

Did they say what pistons they would use ?

I haven't looked what exhaust it has but that was what I was worried about that but all good apparently. I'm pretty good with spanners, I always read up as much as possible and torque everything properly. Still a strange shaped engine to think about working on when you're used to in-line motors ha ha

To be honest they quite easy to rebuild, just be sure use a good competent machine shop & check everything & do research or ask questions if not sure on something.

If Big-end & Main journals on crank are in good order (good chance they are) you only need change shells if show wear & you can easily obtain ACL bearing shells for standard crank size & fit/check clearances-juggle shells to help even up clearances prior to final build. rebore & hone for new pistons is straight forward, just be sure stipulate a bore to piston clearance that suitable for you usage. For road use I would use CP pistons as the piston design allows smaller bore clearance values & they run silent (no slap even on a winter morning) plus are tough pistons & good value for money.

Even doing it yourself it will consume quite a chunk of cash as a good job requires quite a lot of new plus decent quality parts than soon start adding up to 4 figures ...

Cheers mr b, that's great info again. From the last paragraph it seems like even re built engines get the piston slap? Is that right?

Well a race engine may have some slap from cold due to larger clearances due to higher temps it expected to reach. a lot of race engines are pre-heated because of these larger clearance factors.

Problem is people like having race spec this, group A spec that & it not a good thing if you not a race or rally car so correct parts & specs need to be used for the cars use.

CP pistons come with guide on clearance based on usage plus piston design requires less clearance as expansion size changes are better controlled.

The hardest thing I've seen is splitting the block and getting the wrist pins out.

Yes mate, even rebuilt engines slap depending on components used, forged pistons will slap as they are built for abuse and road use doesn't get them as hot as fast.

If I were you I'd just either save a bit of cash for each month or build up parts and run the engine until it goes pop (which could be a while) then re build,