What Head Studs

[...Joshwa]

Hi all,

Just wondering what head studs I should be using for my RB30/25 (RB25 head studs im pretty sure)

And what brand, I know ARP is probably the best/most known. . But looking at them on ebay they are about $250-300. . .

I dont really want to pay that much, is there any other brands that I could be looking at..

Also, I have a set of stock RB25 head studs here, but I was told not to use second hand head studs??

Thanks,

Josh

[Swiper the Fox]

Use Nissan...you get them from Nissan...i use them in all but the most extreme of my engine builds...haven't had a head lift or gasket failure yet.

[...Joshwa]

So dont use the 2nd hand Nissan ones I have here?

[PM-R33]

No.

[Swiper the Fox]

No.

X2 No...new ones from Nissan are cheap around $160 for a set.

[2LV8ETR]

Also, I have a set of stock RB25 head studs here, but I was told not to use second hand head studs??

One factor that makes many engines hard to seal today is the use of aluminum cylinder heads on cast iron blocks. Aluminum heads save weight but expand 1.7 times faster than cast iron when they get hot. The difference in expansion rates creates a lot of motion and scrubbing between the head and block.

You may be able to reuse them with no adverse effects if you make sure the threads are clean and not deformed. However many engines like RB's use "torque-to-yield" (TTY) head bolts that stretch slightly when installed. This provides more even head loading and allows the bolts to hold torque better for improved head gasket sealing.

When the bolts are installed, they're first tightened to a specific torque - then tightened an additional amount that's measured in degrees of rotation. This final twist stretches the bolts to their yield point and creates the elastic clamping force that provides more even loading across the head and gasket.

Because TTY head bolts stretch slightly, some auto makers say they should not be reused when the cylinder head is removed. Reusing TTY bolts will cause them to stretch further, which increases the risk of breakage. A stretched bolt also will not hold the same torque load as before, which may cause a loss of clamping force resulting in head gasket leakage. The best insurance is to replace all TTY bolts when rebuilding and reinstalling a cylinder head with new head bolts. So if your engine uses TTY bolts, replace them. Be sure and torque to the correct setting and in the proper sequence.

[...Joshwa]

No worries. . Thanks heeps for the info. .

I read somewhere that you should do them up to the specified torque, then undo them all, then do them up again. . Or something along the lines of that?

[Swiper the Fox]

No worries. . Thanks heeps for the info. .

I read somewhere that you should do them up to the specified torque, then undo them all, then do them up again. . Or something along the lines of that?

yes its a 5 step process torqueing head studs.

[PM-R33]

For the last step with head studs, when you tighten it to an angle, is there a way you can do it without buying on of those tools? (can't remember what they are called, the ones that are like a torque wrench but display angles).

[...Joshwa]

as above. .

And any links to the process of doing them up?

[PM-R33]

(1) Tighten to 29Nm

(2) Tighten to 98Nm

(3) Loosen to 0Nm

(4) Tighten to 25-34Nm

(5) Tighten to 95-100 degrees

[...Joshwa]

ok. . and which tool is it that i need for the 5th step?

[Swiper the Fox]

ok. . and which tool is it that i need for the 5th step?

1/2 inch drive angle gauge...its got a 1/2 inch socket on the top for your breaker bar to clip in to and a 1/2 inch drive to go into the hex socket you will need to fit the head bolts. its got a round dial on it with angle graduations marked on it.

ill try and dig up a picture.

edit...here ya go.

http://www.ntxtools.com/Merchant/graphics/...01/otc-4554.gif

Edited March 1, 2009 by DiRTgarage

[PM-R33]

Ahhh angle gauge that's what i was thinking of

So no other way to do it without buying an angle gauge ay.....hmmm

EDIT: Actually i just had another look at the engine manual, it says you can tighten it to 93-103Nm for the 5th step....therefore you don't need an angle gauge?

Edited March 1, 2009 by PM-R33

[...Joshwa]

also. . are the main studs the studs in the bottom end that hold the crank cradle in??

Is it a wise idea to replace them also?

[Swiper the Fox]

also. . are the main studs the studs in the bottom end that hold the crank cradle in??

Is it a wise idea to replace them also?

yep they are cheap $60 from Nissan

[Tangles]

my arp head bolts cost $165 for set, aussie dollar was equal to the yankies

320 now - ouch

I shudder to think how much my head rebuild would cost now with the dollar variations (ie poncams were under $800, 8.8mm springs were $300, etc)

[r32r32]

At what point is it recommended to use ARP studs for the head and mains?

[BezerkR32]

if you are asking these questions you probably shouldnt be doing the job.....

also. . are the main studs the studs in the bottom end that hold the crank cradle in??

Is it a wise idea to replace them also?

[...Joshwa]

if you are asking these questions you probably shouldnt be doing the job.....

Whatever mate. . I'm just learning, what a crime that is.