Check out your oil pump as well. Might be worth while replacing it just in case.
On a side note, how did you go licensing your car?
It was a FWD EJ16 when you got it wasnt it?
Any issues, or permits required?

Uhh dude, do you even know what you're talking about?

I've never seen the top of a piston being ripped off....so dunno why you think thats occurred. Fitting one STi piston isn't going to work either, its different to your others!

Sounds like a bearing!

Put an EJ207 in, new oil pump, new gaskets, service your heads, and get it tuned properly with a programmable ECU.

THAT will solve your problem.

the engine is a ej207 balistic, it will be way cheaper to replace the one
the knock only occered on the freeway on the way home stopped as soon as it happened and towed it home ,

sounds like a piston/conrod to me, when engine comes out ill post pics of damage

no the car comes out with the ej20 in it, so u dont have problems with that or awd eather. i had problem with blow off valve tho gfb stealth plumbed back hard didnt make it lol

Big end bearing fail. GX fuel pump. I really gotta ask, what were you thinking putting/leaving a GX fuel pump in it?? Surely someone, somewhere along the way has told you to fit a higher volume capacity fuel pump??

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No more GC8, sad face.
[SIGPIC][/SIGPIC]

Unless the bores is totally clean and the bearings are fine, you really need to consider if it is a cheaper option to pull the engine down inspect it all, replace the necessary parts, machine (if required) then assembly. Sure your labour is free and that's a bonus. If you're confident in giving it a crack, go for it, be sure to weigh up your options though. A factory assembled 207 short motor still represents outstanding value for money.

update us on the progress.

Good luck.

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www.racewars.com.au

Dont waste your time put a sti short motor in if you can hear the noise the cank will be stuffed and by the time you grind it and do pistons you can buy the sti short motor , then rebuild your heads- a few $$ LATER YOU HAVE A NEW MOTOR NOT A RECOND.

I CAN QUOTE YOU ON THE WORK IF YOU LIKE

Way to ignore my advice go get a brand new EJ207 assembled short block from Regents Subaru, swap it in, have peace of mind. Sean from Allstar Garage ran a 10.2 second 1/4 mile with the very same block. If you pull out one piston and replace it, you'll be pulling it out a few months down the track when its broken again. Unless you're REALLY keen to learn how to build motors (every 3 months). Do it once, do it right.

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MY93 Impreza GX 1.8L, 0hp, 0nm

Please don't tell me you were going to replace a piston without checking the bearings?? A knock in a Subaru engine is almost guaranteed to be a bearing, not a failed piston or conrod!

As has been mentioned a LOT of times, GET A BRAND NEW EJ207. It'll save you a lot of time and cost no more than replacing bits and pieces all the time. A bitsa motor will never hang together like a fresh EJ207 will. Make sure you get the fuel system and ECU up to scratch too, so this doesn't happen again!

sorry balistic,talked to the mechanic next door and explained what actualy happens with sup big end and i understood it now lol yeah your prob right i owe u a beer lol.

only problem is i just bought this engine lol spending another 2.8k for a new 207 will be murder but a good idea at the same time.wounder if there cheaper trade or that probably is trade price

044 going in aswell, rx pump was in until 044 was delivered next day, aw well ill see how it goes.