High Coolant Pressure/popping Freezeplug

[Selleen]

Hello, i have a rb25det with a NEO head 8000rpm, 700whp used for drifting. My problem is that the freezeplug in the backside of the head is popping out on launch control/ignition cut/?

oem waterpump

52mm radiator

60 degrees thermostat

It's no problem with the temperature at all if i got some speed, And what i can see the 1.3 bar radiator cap isnt pushing out any water?
I had the same problem with my old head and head gasket too, so I dont think it pushes comp into the coolant system.

Anyone had the same problem?

[GTSBoy]

Sounds like your launch control is causing massively unpleasant vibrations in the material of the head and the welsh plug popping out is the consequence.

You might have to consider either

a) There is something wrong with the way the launch control is doing its thing because surely it shouldn't cause that much shit, or

b) Tapping the hole and screwing in a plug instead.

[KiwiRS4T]

Why are you using a 1.3 bar radiator cap? Sounds like your engine is getting too hot. Do you have an oil cooler?

[Selleen]

Sounds like your launch control is causing massively unpleasant vibrations in the material of the head and the welsh plug popping out is the consequence.

You might have to consider either

a) There is something wrong with the way the launch control is doing its thing because surely it shouldn't cause that much shit, or

b) Tapping the hole and screwing in a plug instead.

Probably, It's not only on launch but when i run rev limiter ignition cut it pops too, So i dont think the launch control is the problem.

Why are you using a 1.3 bar radiator cap? Sounds like your engine is getting too hot. Do you have an oil cooler?

Shouldnt i? I dont think heat is the problem, oil cooler and 52mm alu radiator.

When i use fuel cut rev limiter i dont have that problem!

[GTSBoy]

Probably, It's not only on launch but when i run rev limiter ignition cut it pops too, So i dont think the launch control is the problem.

When i use fuel cut rev limiter i dont have that problem!

I think my statement still stands. If ignition cut is causing that much pain and horror to the shape of the head, then there is something nasty about it.

[GTRPSI]

It's a common issue on high output rb,s.

Most people go around the outside of the seat on the head with a center punch to expand the hole to stake the plug in after its fitted.

My way of avoiding it is to weld it shut with a alloy bung.

[STATUS]

have you logged coolant pressure? could be lifting heads and blowing them out