HELP what size OEM con rod bolt socket, 10mm to small, 11mm to big

I’m interested too as I’ll be fitting some ARPs soon.

Are you using a hex or 12 point socket?
 
hex 10mm to small, 12 point 11mm to big 12point 7/16 to big. (I have the 3/8 12 point for the new ARPs) but cannot work the out the OEM size, maybe 12 point 10mm??? visually thou the bolt head looks bigger than a 10MM.?? completely stuck with the car in bits!
 
I would have thought it would be metric being french! Try a 10mm 12 point? Got a picture of them?
 
The hex bolt pictured,
Yes reading up French cars prefer the 12 point socket? I honestly never knew. I gonna run out and buy one anyhow.
 
thinking could be my 11mm socket is old/worn.
Anyone else have the knowledge on the actual socket size required?
 
Yes its a straight swap, you need an imperial 3/8" (1/4 drive) 12 point socket for the ARP bolts and torque up to spec.
Going to post a guide for you all with pics, for rod bearings and bolts, its a messy job though as the oil bleeds from the engine etc.
I had a small knocking so I changed the con rod bearings for a new set OEM and it solved the problem.
if you are changing the bolts and you done 100km why not swap out the bearings at the same time.
Also part of this is another must do job, 4 bolts and you can drop the front radiator sub frame/support (thats in the way to remove sump). So you can refurb that with drill wire brush and black satin Hammerite. Some people say you can jack the engine with out removing the sub frame, but its so quick and easy and I would not want to risk stressing the OEM mainfold flexi`s.
 
Yes its a straight swap, you need an imperial 3/8" (1/4 drive) 12 point socket for the ARP bolts and torque up to spec.
Going to post a guide for you all with pics, for rod bearings and bolts, its a messy job though as the oil bleeds from the engine etc.
I had a small knocking so I changed the con rod bearings for a new set OEM and it solved the problem.
if you are changing the bolts and you done 100km why not swap out the bearings at the same time.
Also part of this is another must do job, 4 bolts and you can drop the front radiator sub frame/support (thats in the way to remove sump). So you can refurb that with drill wire brush and black satin Hammerite. Some people say you can jack the engine with out removing the sub frame, but its so quick and easy and I would not want to risk stressing the OEM mainfold flexi`s.

Why does it need to be 1/4 drive for the ARP bolts?
 
1/4 or 3/8 drive is fine for the ARP bolts.
The sump bolts (all 22 of them)are a Torx E8, 4 bolts are counter sunk into the flywheel end of the sump housing by a good 12cm so a 1/4 inch drive E8 torx is best for that as its slimmer.