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Good Evening everyone hope you all well and keeping safe.

I am busy with a rb30/25 build and would like to finalize my build in the next 2 months however I am sitting with a little problem hopefully you guys can advise.

My questions is what is the max hp the stock Rb25det head bolts can handle?

I have been trying to source Arp head studs same as Rb25det  but Unfortunately none of the suppliers in Sount Africa have stock and are all waiting for containers to come in. Been about 4 months and i would like to start driving the car.

I have googled and came across a discussion that says they sitting at around 600hp on stock Rb25det head bolts. Not sure if this can be confirmed and if anyone has done something like this.

Build breakdown as follows:

Rb30 block

Stock 86.5mm pistons with Hastings rings

Stock rods but shot peened and Arp rod bolts

Rotating assembly balanced

Oil galleries drilled

Rb25det cosmetic head gasket

Acl main and big end bearings

Rb25det oil pump and flowed 

New water pump

Rb25det damper pulley

1.5mm oil restrictors

Stock crank 

Rb25det head ported and flowed intake and exhaust

Port matched intake

Rb26 valves,  quarters , retainers, valve springs, Lifters, cams cut 270

So the head is solid lifters and solid cams

Top mount branch pic attached built by Marius Fullboost South Africa 

38mm waste gate

Greddy blow off valves 

Stainless boost pipes

HKS Fuel rail

Lucas 1200cc injectors 

2 x bosch 044

Turbonetics Hurricane 7868 aka Benita 

Spitronics Mercury Fuel Management

That about where I am at the moment.

Any input as usual is appreciated and thanking you in advance for all the help and guidance so far with this build?

Thanks Brian Chev R

 

 

 

 

 

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I would avoid the OEM head bolts, as they're TTY and should not be re-used.

Also they stretch pretty easy, so I would personally wait till you can get your hands on the ARP head studs/nuts.

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