Jump to content
SAU Community

Head Bolts Or Studs?

stuartlaw_78

By stuartlaw_78,
in General Automotive Discussion

 Share

Recommended Posts

stuartlaw_78 Community Regular

stuartlaw_78

Posted
Posted

Hi all....

I'm looking at buying some head bolts for my engine when it goes back together but want to boost it up and have been told that studs are a lot better for this application....

Can anyone confirm this and more importantly, is there anything I need to know about putting in studs? Is it just a matter of screwing in the studs to the block and then sliding the head over them, then tightening them to specific torque settings??

Is there more to it when screwing them to the block first? Do they have to be a specific tightness in the block before I put the head on??

Link to comment
https://www.sau.com.au/forums/topic/96388-head-bolts-or-studs/
Share on other sites
Craved Grand Master

Craved

Posted
Posted

i have spoken to my Mechanic abouts these.. and you VERY STRONGLY recommend the studs over bolts. the deal with the studs is that they allow you to put a more accurate amount of torque through them and the wont stretch as much so the clamping force on the head/block is greater.

i'll be using them in the 3L build but if you dont want to spend the $200 then you should use some Moly grease on the head bolts so that they wil tighten up to the correct torque, the grease is for engine building and breaks down, but allows for less restriction on the thread which means the torque needed to turn them is less.... hence the torque is closer to correct when you bolt them up to the 99-103 Nm

not sure on how they are applied into the block though, can find out easy enough.

Warpspeed Experienced

Warpspeed

Posted
Posted

Studs are definitely stronger, and a further advantage is that you can leave the studs sitting in the block when you take the head off. If you are going to be continually taking the engine apart regularly, as in a real race engine, the threads in the block will not wear out from the constant removal and re torquing. That is the good news.

The bad news is that the head becomes a bitch to get off. It has to be lifted STRAIGHT up off the studs, if it goes slightly crooked, the studs can jam in the cylinder head holes. Another thing is that Skyline head gaskets do not have a reputation for giving trouble, and neither do the standard factory head bolts. As both work perfectly fine as they are, why change them ?

Some guys really get a kick out of spending money on their cars. If I told you that a set of Titanium wheel nuts cost $3,000 dollars and were twice as strong as the factory wheel nuts and saved 0.5Kg in weight, would you buy a set ?

That is what it really comes down to. If a set of head studs make you feel better, then get yourself a set. Otherwise the standard head bolts will work fine, it is entirely up to you.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • 25RBGT
      Got this r31 silhouette flood car to rebuild.

      By 25RBGT · Posted

      Boot is going to be replaced eventually. I just wire brushed what I could and rust converted. Then painted in rust kill primer. the spoiler also got repainted and plugs replaced on the ends. The under side of the bonnet is going to be black also, currently white. But red on the top side, same colour code as the silo to begin.
    • Shoota_77
      Car Rotisserie

      By Shoota_77 · Posted

      Hi guys, has anyone either purchased or built themselves a rotisserie for their car before? I can only just justify the need for one hence why I should just make one but at the same time, if I make one I can kiss another 4 weeks of potentially productive car working time goodbye because I'm building a bloody rotisserie....  I mainly want it for the application of the body deadener.  Cleaning the old stuff off, priming and then colour over the deadener doesn't worry me, it's just the application using the Schutz Gun that I feel would achieve a significantly better finish painting it side on and keeping the Schutz Gun upright.  I don't think they would work well on the side let alone almost upside down for some areas.  If the product I use (Terosun, etc) could work through a HVLP ok then it might be ok to apply without the rotisserie.   I can get one of these style ones for about $1200 which is pretty good value-     I reckon if I made one it would cost around $500 but it's more the time that it would take is more of a killer than the cost.  They look to hold their value pretty well second hand so I could always sell it after using it and realistically only lose $200-$300 at worst.  Or keep it and buy another project when this one finally sees the light of day... Anyone selling one...? Cheers!  
    • GTSBoy
      Stock rb25det neo questions

      By GTSBoy · Posted

      While it is a very nice idea to put card style AFMs into the charge pipe (post intercooler, obviously), the position of the AFM and the recirc valve relative to each other starts to become something that you really have to consider. The situation: The stock AFM is located upstream the turbo, and the recirc valve return is located between the AFM and the turbo inlet, aimed at the turbo inlet, so that it flows away from and not through the AFM. Thus, once metered air is not metered again, neither flowing forwards, or backwards, when vented out of the charge pipe. When you put the AFM between the turbo outlet and the TB, there is a volume of pressurised charge pipe upstream of the AFM and there is a volume of pressurised pipe downstream of the AFM. When the recirc valve opens and vents the charge pipe, air is going to flow from both ends of the charge pipe towards the recirc valve. If the recirc valve is in the stock location, then the section between it and the TB doesn't really matter here - you're not going to try to put the AFM in that piece of pipe. But the AFM will likely be somewhere between the intercooler and the recirc valve, So the entire charge pipe volume from that position (upstream of the AFM, back through the intercooler, to the turbo outlet) is going to flow through the AFM, get registered as combustion air, cause the ECU to fuel for it, but get dumped out of the recirc valve and you will end up with a typical BOV related rich spike. So ideally you want to put the AFM as close to the TB as possible (so, just upstream of the crossover pipe, assuming that the stock crossover is still in use, or, just before the TB if an FFP is being used) and locate the recirc valve at the turbo outlet. Recirc valve at the turbo outlet is the new normal for things like EFRs anyway. In the even of a recirc valve opening dumping all the air in the charge pipe, pretty much all of it is going to go backwards, from the TB to the recirc valve near the turbo outlet. But only a small portion of it (that between the TB and the AFM) will pass through the AFM, and it will pass through going backwards. The card style AFMs are somewhat more immune to reading flow that passes through them in reverse than older AFMs are, so you should absolutely minimise the rich pulse behaviour associated with the unavoidable outcome of having both a recirc valve and an AFM in the charge pipe.
    • joshuaho96
      Rb25det Belts Change

      By joshuaho96 · Posted

      Yep, in my case as soon as I started hearing weird noises I backed off the tension until it sounded normal again. Delicate balance between enough tension to avoid that cold start slip and too much damaging things.
    • silviaz
      Rb25det Belts Change

      By silviaz · Posted

      nvm this comment
×
×
  • Create New...