gtb, sti heads

[maserati mick]

thinking of doing a bit of engine work on my foz getting cambelt replaced and thinking of ugrading the heads with better flowing gtb one's has anyone done this also would you need an sti longblock to install sti piston and rods or can you install sti pistons on a non sti block??

[Dacca]

You can install Sti bit into non Sti block.

Mind the squirters if your using a closed deck block.

[rex-leggy]

 Dacca said:

Mind the squirters if your using a closed deck block.

? more info

[maserati mick]

i just thought that if forged pistons were to be installed the block would need to be machined to ensure clearence between piston and the bore wall are sweet. ;D

also the sti pistons being forged have a lower compression ratio to accomodate for the higher boost levels.does the sti range use a diffrent thickness of head gasket??

im planing to use my current block which is the same as a v5v6 wrx non sti

[maserati mick]

cast pistons run a tighter clearence and expand less when they heat up and are alot quiter

forged pistons expand more as they heat up which requires extra piston to bore clearence ???

[rex-leggy]

 maserati mick said:

cast pistons run a tighter clearence and expand less when they heat up and are alot quiter

forged pistons expand more as they heat up which requires extra piston to bore clearence ???

this is true . the kit i got was for the standard bore size so no issues there in my case . i believe thats one of the reasons people go over sized just to get the tolerances as close as possible or to get rid of bore damage.

if your running a v5/6 block its the same as mine (except i run closed deck) and i run gtb heads with je forgies . and genuine head gaskets .

no machining was needed

my question was to dacca about the oil squirters in a closed deck as i run a closed deck with oil squirters

[Guest vf20/21bg5]

 rex-leggy']

[quote name='maserati mick said:

cast pistons run a tighter clearence and expand less when they heat up and are alot quiter

forged pistons expand more as they heat up which requires extra piston to bore clearence ???

/quote]

this is true . the kit i got was for the standard bore size so no issues there in my case . i believe thats one of the reasons people go over sized just to get the tolerances as close as possible or to get rid of bore damage.

if your running a v5/6 block its the same as mine (except i run closed deck) and i run gtb heads with je forgies . and genuine head gaskets .

no machining was needed

my question was to dacca about the oil squirters in a closed deck as i run a closed deck with oil squirters

i run the squirters too with no trouble around closed deck and forgies, maybe thrs another aplication to watch out for the squirters on?

[Dacca]

 maserati mick said:

cast pistons run a tighter clearence and expand less when they heat up and are alot quiter

forged pistons expand more as they heat up which requires extra piston to bore clearence ???

Not quite true,aftermarket forged pistons expamd a LOT more than factory subaru ones.

Subaru run .0005 piston to bore clearence from factory

Aftermarkets would run .002 minimum

[Dacca]

 rex-leggy']

[quote name='Dacca said:

Mind the squirters if your using a closed deck block.

/quote]

? more info

I have fitted WISECO piston that required the squirters to be removed or the pistons modified

[maserati mick]

what kind of block is the ej205 v5v6 have anyway closed open deck?? ???

[Guest vf20/21bg5]

 Dacca']

[quote name='Dacca said:

Mind the squirters if your using a closed deck block.

/quote]

? more info

I have fitted WISECO piston that required the squirters to be removed or the pistons modified

glad i ran the CP's then had no trouble with squirter clearances

[rex-leggy]

 CP93MM']

[quote name='Dacca said:

Mind the squirters if your using a closed deck block.

/quote]

? more info

I have fitted WISECO piston that required the squirters to be removed or the pistons modified

glad i ran the CP's then had no trouble with squirter clearances

+1 for JE but thats going away in the memory bank as its somthing i failed to check :-X .....but would've found after turning over by hand

[maserati mick]

got a sti v4 longblock lined up heads may need a rebuild has crank new head gasket pistons rods etc what should i do first will everything bolt up??my factory engine is ej205 v5v6 would i need to change ecu also or retain factory

[rex-leggy]

if the heads need a rebuild then the headgaskets are rubbish anyway because you will need new ones.

because your existing engine is a v5/6 the v3/4 heads will not work with you setup, because how the intake manifold bolts on to the heads is different (v3/4 is phase one and v5/6 is phase two).

there's spacers you can buy http://www.carldavey.co.uk/product.php?id=16.

wats wrong with your existing heads i dont know much about the foresters but do they have shim over bucket?

or do you want a better cam profile for power?

[maserati mick]

im hoping to recieve the manifold with the longblock im starting to think maybe it would be shitloads easier to go with a phase 2 longblock

still aint sure what type of heads the phase 2 forester has??