The different flavors of ARP head studs

[Rusty67]

ARP makes a great product. I think everyone knows that by now. The thing is, they make head studs with these so called "optional features". I'm wondering if these extras are worth it for me.

12-point nuts
ARP says that a 12-point nut will allow you to retorque the head without removing the valve train. Is this even neccessary on a small block Ford ? Is this something that depends more on the valve springs you use then the type of head ? I'm just wondering if this will really save me any time at all.

undercut studs
From what I've read, the way I understand it is that an undercut stud has a small amount of metal removed from the stud in the area between the threads so that the studs are slightly more flexable. This supposedly helps to maintain the preload on the nut should lose some compression.

I did a search on google and read in another forum that the undercut studs are weaker. This guy called ARP and the tech told him undercut studs are better for street use and regular studs are better for race only engines.

I can't see a properly installed head gasket going south when used with studs and the head being correctly torqued. Are undercut studs worth the extra cash ?

 

[rbohm]

personally i dont think under cut studs are worth the extra money. i also dont feel the need to use studs to secure the heads on a street engine either.

 

[Rusty67]

I've talked to several knowledgable people and everyone agrees that studs help to reduce head gasket failure.

Any comments on the 12 point nuts ?

 

[rbohm]

12 point bolts and nuts allow for smaller sockets, while still allowing for the larger bolts and nuts. i dont disagree about studs allowing for more consistent clamping force on the head gasket, i just dont think they are needed for the street. that and they make it harder to remove the head in the car when the time does come.

 

[CraigMBA]

Read impossible to remove the head with the engine installed.

Head studs are for blown/turbod/sprayed applications making 600+ hp. Not practical for a street car.

 

[Rusty67]

Read impossible to remove the head with the engine installed.

Head studs are for blown/turbod/sprayed applications making 600+ hp. Not practical for a street car.

Maybe if it is a big block. Or maybe if the car is a 65-66. On a 302 you can get the heads out with studs in the car. You may have to jack the motor on one side to gain the extra clearance but it can be done.

I want studs for reliability. I don't really care about being practical on this issue.

At this point what I really want to know is, are the 12 point nuts worth my money ? Do I need them ? I thought I would be able to retorque the heads without removing the valve springs regaurldess of weather or not I used the smaller nuts or not.

 

[CraigMBA]

I have a '65. 67-later cars you can use studs, even though they will still be a pain.

 

[dennis112]

Maybe I am missing something here.

Modern ARP studs are broached with an allen head screw hole in the top. That allows the stud to be easily removed, just like a bolt. Maybe easier since studs are installed only finger tight.

 

[brianj5600]

It is tight, but I have pulled heads off my 351 in a 67.

 

[Rusty67]

I've seen the hole studs are inconvinent for pulling the head while its still in the car argument in damn near every thread where studs come up. Honestly guys I'm not interested in that informatino as I've read it one too many times (no offense to anyone).

What I really want to know at this point is: Are 12 point nuts worth the extra cash ? I was under the impression that you can retorque heads on small block Fords just fine without these, am I wrong here ?

 

[Spanish Dave]

I've seen the hole studs are inconvinent for pulling the head while its still in the car argument in damn near every thread where studs come up. Honestly guys I'm not interested in that informatino as I've read it one too many times (no offense to anyone).

What I really want to know at this point is: Are 12 point nuts worth the extra cash ? I was under the impression that you can retorque heads on small block Fords just fine without these, am I wrong here ?

I think 12 point nuts *should* fit better in a 12 point socket ... but an ordinary 6 flat nut should not be any diiferent IMHO .... I would go for the cheaper of the 2. I think it would depend on your rockers ... I have the Summit *fat-boy* roller rockers and these are no problem. So the Harland Sharp or Crane Gold rockers should be OK

 

[Rusty67]

Any other comments on the merit of 12 point nuts for a small block Ford head ?

 

[Steel123]

I have a '65. 67-later cars you can use studs, even though they will still be a pain