Quick Question

[nbskyline]

Well, my coolant keeps getting air in to it. Coolant and oil temps rising, bubbling after shut down. Hearing a slight knock on the turbo side

No coolant in oil/oil in coolant or white smoke? But...120 psi on # 6 and 128 psi on # 5, others are around 150 psi. I am weary of doing another headgasket??
If I were to buy a used engine ( good compression ) replace headgasket and studs, should I need to get the head skimmed??

I know I have had alot of questions and I appreciate all answers

[nbskyline]

no one??

[mcfly]

you only need to skym the head if it's not true(straight)
So typically it doesn't need to be done unless someone over heated the motor.

You are not losing any coolant or smoking? Have you properly bled your cooling system?

[Skym]

Common problem for 5th and 6th cylinder to get too much air due to front mount intake plenum design and run lean, which causes headgasket, shortblock, piston rings to fail on those 2 cylinders. Normally you flow test injectors and put the highest flowng injector into 6th, next highest flowing injector into 5th, etc. What makes it worse is 5th, 6th cylinders get the hottest due to that part of engine being close to firewall (hot air builds up around that area).

Nismo intake plenum supposedly has places for extra injectors on 5th, 6th cylinders.

I would think there's a ECU tune problem causing the headgasket failure on 5th, 6th cylinder.

Some ECU's like Link, Motec, etc have individual cylinder trim for fuel, so can make those cylinders run richer.

[NismoS-tune]

The nismo intake plenum can use a second set of injectors