what size overbore pistons for rebuild?
 

Hi,

as I wrote in the other thread it seems like my engine has a serious problem - supposedly a bad piston.

As it takes some time to order (and receive) all the needed parts, forged rods, forged pistons and arp head studs - what size overbore would you use.
(I think the answer will be - ask the engine rebuilder! But that makes the ordering roces even longer - because it will be end of the week until the engine is torn apart and take another two weeks until the new components have arrived - then install into the engine, install everything back into the car... bloody long time.

So - is there something like a common size (it's a 1,6l with OEM 78mm bore - so the option is 78,5mm or 79mm pistons) I don't think it does matter for the rods as they are the same for even 1,6 and 1,8 cars.

Thanks for your continuous help and advice!

To quote Smoky

There is no substitute for cubic inches

the 79mm would be my choice, better chance the bores will clean up with the larger size as well.

I went .5 over just in case something bad happened so I could hopefully bore again and retry.

I went with the 79mm for my 1.6.

Measure twice, cut once.
 

I would wait to see if your block needs an overbore. On my FE3, the previous owner had cracked a piston. When I sent the bare block to the machine shop, the cylinder walls were still 86mm. So I just had it honed and ready to drop in another set of 86mm pistons.

1mm overbore used in my build...

85.5 here. dont go more then 1-1.5mm to be on safer side