RB30 ARP Main torque causing bearing failure

[lolo.37]

RB30 ARP Main torque causing bearing failure

I have an RB2530NEO GTX3582r 1.7bar and last summer I broke some bearings and heated a spool Rod. 
5 main bearings worn and 2 or 3 rod bearings worn aswell. 

I finally put the engine back in the car after this bearing and rod failure.

I thought it was caused from oil starvation on a too long high speed run 200kmh+ 1.7bar (gtx3582) but there was no oil thrown in the engine bay through the oil catch can. 

(oiling setup : RB3025 neo, N1 oil pump, baffled and extended sump, no squirters, 1 restrictor 1.2mm, 1 blocked,1 VTC 2mm, rear and exhaust side oil return, cranckase venting on intake side. I now changed back to RB25DET NEO OEM oil pump)

Now a French RB25 specialist tells me that 60ft.lb / 81N.m on the main bearings with ARP make 0.03mm of ovalisation on the main tunel. 
And this could cause bearing failure when passing 500+hp. 

He tells standards bolts with OEM torque spec is ideal untill 1000Hp. 

What do you specialist guys think about it? 
I'm afraid to blow it up again... 

[Dale FZ1]

Sorry to hear this happened for you Laurent.

I wouldn't blindly accept that conclusion.

How high are you revving the engine?

Look closely at bearing clearances, and oil spec.

Have the journals been refinished/polished?  If so the standard of finish should be investigated too.

[zebra]

What were the bearing clearances?

 

A 0.03mm out of round would show when checking the mains

[Scott Black]

Plausible however that's why you get the mains torqued down, honed and measured as part of the machining work

[DCIEVE]

The rb30 cranks walk around so you need plenty of clearance and oil pressure. And don't rev the thing too hard. As above, you set clearances with the studs torqued so that's not it unless the build was botched.

[33GTRV]

Who built the engine? Any builder worth half his wieght would have pre torqued the studs on yne mains and checked and line bored as required. Rbs are renowned for it