Knock knock, who's there? BIG ENDS!

[Wiretap]

 evowrx said:

Would piston slap just begin out of the blue? i thought the concept of piston slap was the larger bore clearance with forged pistons when cold.

Piston slap will start suddenly if you break the skirt off a piston, which isn't exactly the rarest occurrence around.

[Guest]

good to know first time ive heard of it normally see melted pistons/big ends.

what causes the skirt to break off?

[Drunkenmonkey]

Must be my phone but that knock sounded l a lot heavier than my piston slap sounded, like thorpys Beb on agm night.

Is the car down on power at all?

[funkytown]

 Drunkenmonkey said:

That's a hell of a knock sounds like big end to me,

Got a long screw driver? One trick is hold it on places and move around see where it's loudest with your ear on the other end

doesn't sound anything like as bad as Thorpy's. usually when the throttle is blipped like the OP did in the pics it induces substantially more rattle and it doesn't sound like it to me.

Need someone that really knows subbies to listen to it in the flesh.

I''ll ask again - whats it sound like when its nice and warmed up?

[Wiretap]

Typical quiet bigend noise

and

Typical 'completely F*CKED' bigend noise

[funkytown]

yup that first link see how the knock increases on throttle blip.

different to OP's

[ODB]

Perhaps stop trying to diagnose over the intermanet and take car to reputable Subaru garage to be fixxored?

[Drunkenmonkey]

 funkytown said:

yup that first link see how the knock increases on throttle blip.

different to OP's

I see ya point

What about it you apply the clutch does it go away?

[gazzy2000]

what about oil? QT must be gettin colder now this time of year, cud be wrong oil??

Like funky says, whats it sound like when fully hot would be a better indication

THATS MY FIDDY

[ODB]

 gazzy2000 said:

THATS MY FIDDY

[gazzy2000]

und if that was my rev C BH, und the donk was borked

- i wud get a v7 shortie

- grab your mates one and use all the single turbo shyte off it incl STI ECU etc etc

- make yours a single turbo - bit of wiring to do, Reuben will do it for $$

- sell bits left over i.e. shortblocks, heads or WHY, incl injectors etc etc

FYI - the Compression Ratio (CR) is engineered into the pistons, so getting a new STI v7 shortie will be all good in the hood for the v5/6 STI ECU

[Guest]

 gazzy2000 said:

und if that was my rev C BH, und the donk was borked

- i wud get a v7 shortie

- grab your mates one and use all the single turbo shyte off it incl STI ECU etc etc

- make yours a single turbo - bit of wiring to do, Reuben will do it for $$

- sell bits left over i.e. shortblocks, heads or WHY, incl injectors etc etc

FYI - the Compression Ratio (CR) is engineered into the pistons, so getting a new STI v7 shortie will be all good in the hood for the v5/6 STI ECU

is comp the same between v5 sti and v7? you put in a v5 ecu you cant tune it to run the best for comp difference...im not saying it wont work just if theres a better option?

[gazzy2000]

 evowrx']

[quote name='gazzy2000 said:

und if that was my rev C BH, und the donk was borked

- i wud get a v7 shortie

- grab your mates one and use all the single turbo shyte off it incl STI ECU etc etc

- make yours a single turbo - bit of wiring to do, Reuben will do it for $$

- sell bits left over i.e. shortblocks, heads or WHY, incl injectors etc etc

FYI - the Compression Ratio (CR) is engineered into the pistons, so getting a new STI v7 shortie will be all good in the hood for the v5/6 STI ECU

/quote]

is comp the same between v5 sti and v7? you put in a v5 ecu you cant tune it to run the best for comp difference...im not saying it wont work just if theres a better option?

yes is the same

if it were me... i would prolly try n find some cheap STI v5/6 heads just to make sure its all STI (dunno.. but STI heads may not be the same as the BH TT ones i.e. cams and port size etc)

[funkytown]

nekk minit: FS mint BH long block... can be heard running :-X

[Guest]

 gazzy2000']

[quote name='gazzy2000 said:

und if that was my rev C BH, und the donk was borked

- i wud get a v7 shortie

- grab your mates one and use all the single turbo shyte off it incl STI ECU etc etc

- make yours a single turbo - bit of wiring to do, Reuben will do it for $$

- sell bits left over i.e. shortblocks, heads or WHY, incl injectors etc etc

FYI - the Compression Ratio (CR) is engineered into the pistons, so getting a new STI v7 shortie will be all good in the hood for the v5/6 STI ECU

/quote]

is comp the same between v5 sti and v7? you put in a v5 ecu you cant tune it to run the best for comp difference...im not saying it wont work just if theres a better option?

yes is the same

if it were me... i would prolly try n find some cheap STI v5/6 heads just to make sure its all STI (dunno.. but STI heads may not be the same as the BH TT ones i.e. cams and port size etc)

yea i would like to know on phase 2 206kw legacy how they compare cam/port wise to sti. might be cheaper for me when i get there. lot of info on early ones.

[Drunkenmonkey]

There was a guy on here who said he was running be b4 heads and I saw it hit the 400 kw mark on the dyno

[gazzy2000]

 Drunkenmonkey said:

There was a guy on here who said he was running be b4 heads and I saw it hit the 400 kw mark on the dyno

all good then aye... all he wud need is the single turbo bits off his mates car and a new v7 STI shortie.

Oh and make sure you got the right head gaskets i.e. for an STI not a BH legacy (just incase you know you are not farking with the CR)

this is all assuming his sucko moto is indeed borked

[Skinon!]

 gazzy2000 said:

und if that was my rev C BH, und the donk was borked

- i wud get a v7 shortie

- grab your mates one and use all the single turbo shyte off it incl STI ECU etc etc

- make yours a single turbo - bit of wiring to do, Reuben will do it for $$

- sell bits left over i.e. shortblocks, heads or WHY, incl injectors etc etc

FYI - the Compression Ratio (CR) is engineered into the pistons, so getting a new STI v7 shortie will be all good in the hood for the v5/6 STI ECU

My mates got exactly the same car as me but auto and had a front left impact behind the firewall, engines still good and apparently it goes hard as its had some injectors and hybrid turbos put on, but he's not exactly sure hwat ecu it's running...

Im always weary of this and i dont really want mine far from stockish, as it is a work/mountain car and if i want raw speed all getta gtr or rotor/v8 toy....

[Skinon!]

 Wiretap said:

Typical quiet bigend noise

and

Typical 'completely F*CKED' bigend noise

Hmmm judging from these videos, mine doesn't have the hard out metallic 'ping' noise. im pretty sure i have a exhaust leak around exhaust maaaaybe headers too but not certain.

When its warm it doesnt change much, like when im drivin i cant hear it, unless im against like a drivethru wall or something. Car still goes good as normal but dont really wanna test it too much at the mo haha...

[Guest]

thought your mates was a tt wasnt sure where the single turbo touch came from.

just listened to that video now im home from work imo doesnt sound like a big end. not sure what it would be though. does sound regular though.

[gazzy2000]

 Skinon! said:

My mates got exactly the same car as me but auto and had a front left impact behind the firewall, engines still good and apparently it goes hard as its had some injectors and hybrid turbos put on, but he's not exactly sure hwat ecu it's running...

Im always weary of this and i dont really want mine far from stockish, as it is a work/mountain car and if i want raw speed all getta gtr or rotor/v8 toy....

ah yip hear what you are saying...

well yr mate's one is a good option then, youd just want to find out if because it has been tinkered with, is it running the same/right CR for your car.

But yea, if the CR is right.. grab his long block and swap yr TT shyte onto it and youre away.

[B4 2000]

if your mate has an auto gen 3 legacy and you have a Rev C manual then they both have the same CR.

just swap engines and you're good to go, if you really did run bearings that is. As i don't think you did going by the vid you posted.

[Skinon!]

Ah k yea im thinking the straight swap out would be best, hearin people say it might not be the big ends is a daaaamn relief!

Really the last thing i need right now. anyway off to catch up with Reuben on sat so hopefully will have a bit more insight.

[WRXONP]

like said above and like i said straight away - rod knock will definatly get louder as throttle is pressed - and get louder with higher RPM like that first video in that link

typical rod knock sound

thats what rod knock sounds like regardless of engine - wether it be a v8 - inline 4 - boxer - straight 6 or whatever -

loud - distinctive - increases with rpm -

piston slap is very common on old worn subarus - honestly havent herd one that doesnt piston slap - yes it gets quieter when warm but it doesnt go away

[WRXONP]

 Drunkenmonkey']

There was a guy on here who said he was running be b4 heads and I saw it hit the 400 kw mark on the dyno

Rated R - 425 kw or something like that on nos - he said b4 heads had bigger ports - i wouldnt argue to the point if he runs that much power !

[quote name='gazzy2000 said:

FYI - the Compression Ratio (CR) is engineered into the pistons, so getting a new STI v7 shortie will be all good in the hood for the v5/6 STI ECU

head gasket thickness also has a huge effect on CR aswell as piston shape / height