Would these pistons fit a G60 block ?

[BigTartanJudge 0]

Hi,

 

Can some of the more technically-minded people tell me if a set of high-spec 84 mm pistons would be suitable for fitting to a G60 block for use in an engine with a totally upgraded spec ?

 

Much appreciated :D

[RACK 0]

They might be slightly too big. With boring the cylinders out to 84mm the walls could be on the thin side. I think 83mm is about the limit.

[h100vw 0]

83mm seems to be the normal oversize piston. Thats for 1900ish cc. To get more capacity usually involves a longer throw crank.

Gavin

[W3RKD 0]

anyone who would bore your block to 84mm wants shooting

[VEEDUBBED 0]

I've checked the clearance

with a G60 metal head gasket,

there's plenty of saftey margin,

I used to fit Lancia Delta intergrale

pistons(84mm) into fiat uno turbo engines(81mm),

1301cc into 1500cc,using a normally asp.

delta head gasket with no probs,exept broken

gearboxes...

Struan,that you mate?,

if you do decide to fit the pistons

try to get hold of a deck plate,

heat the block/deckplate THEN

bore the block, plateau hone/flex hone etc,

You will have NO oil/blowby probs.

And the piston/rings will hold 1.8 bar turbo

press. no problem(with correct tuning..)

[Henny 0]

84mm pistons WILL fit into a PG/1H block....

 

 

 

 

...and then the engine will last for about 10 minutes of running before the centre two bores crack and become one large wet oily mess... :roll: :lol:

 

Ignore the spacing on the head gasket, look at a 1H or PG block from the crank end and you'll realise (if you have any mechanical experience) just why no-one uses more than 83mm pistons... It's a bit close in there with all of the oil and waterways around the cylinders! :crazyeyes: :lol:

[VEEDUBBED 0]

Strange,i've never encountered

any problems on other engines

when using 84mm pistons in 81mm

bores,and i'm talking about heavily boosted

small engines,the difference with,say, a fiat

uno turbo engine(1301cc) and a Vw 8v block

oil ways,coolant galleries is not a lot,their

quite similer.

One could say that about trying to turbocharge

an M3 bmw(new shape),that can't be done

because that engine's bores are maxed out already,one has to use the

2.8 block,not the 3.2.

Anyway,if you do go ahead and use these pistons

the most important thing is that the boring work

has to be done very accuratly prefrebly using a

heated deck plate.

[Henny 0]

VEEDUBBED, I'm not saying you can't run 84mm pistons in an 81mm uno block or other engines... I'm saying you CAN'T use 84mm pistons in a G60 block! :roll: There are oilways VERY close to the linings of the cylinders in the G60 engine... in fact, one of them actually goes through the liner at the bottom where the oil squirter which cools the bottom of the piston crown comes through! :lol:

 

The FACT is that you CAN overbore the block to 84mm without hitting any oilways and waterways, BUT as soon as you use the engine in anger with any level of boost the cylinder walls WILL crack (normally between 2 and 3) :roll: