Searched for a lonnnggg time. The problem? People say our stock head studs will stretch with the boost in the mid 20s and higher. The answer? ARP units. However, there are 2 issues that I would like to know if they are purely "here-say" or if it has actually happened to someone. First off, has anyone actually had headgasket failure due to the stock ones stretching. I have searched my butt off and I can't find anyone who has stretched the stock headstuds. Second, I hear that the ARP units like to back themselves out. Has this happened to anyone running the ARPs? Again, I have searched and I haven't seen anyone with this problem as of yet either. So, either A. I am not searching the right words, or B. This was apparently a bigger problem with the first and second gen dsm's and everyone figures it will also apply to the Evo. Can anyone help me out?

 

bump for good Q

 

i think because most people install them when they do the cams. its only an extraa 95$
alot of owners just like buying insurance.

 

Run high boost with out them and let us know.

 

From what I've been told only excessively high in cylinder pressure occurring as a result of high boost with the presence of detonation can contribute to stretching the stock head bolts. For the most part theyre a simple modification to do although I would personally hesitate to touch anything under the valve cover on such a new car.

Also, on a lightly modified car if you were to stretch the stock head bolts and blow the headgasket you'd have to pull the head to replace it, which is supposedly the proper way to change head bolts anyway.

My advice would be to do them only if your doing cams at the same time, otherwise don't disturb anything.

 

they give ya piece of mind for only 95 bucks

 

This is pretty much the reason why I changed mine.

 

Great question. We've all swallowed this one like a pill--ARP head studs-- and "everyone else does it so it must be important" philosophy is usually good. But it'd be interesting if someone who has built and raced a lot of dsms (especially 4G63s) came back and said "totally unnecessary". Kind of interesting that there isn't one single competitor (to speak of) for this mod. But my guess is that it's probably going to be one of those things that'll be advised by the experienced and that nobody is going to challenge at the cost of serious mishaps.

 

"You pay to play"... decide for yourself if a little peace of mind is worth it. I suggest them do to how "cheap" they are vs. having to pay to have the head pulled. Then again, that is a whole other arguement.

 

I would agree with Zeus and most other people so far. Just get them replaced to be on the safe side.

 

I've already purchased a set of ARP headstuds that I haven't installed yet and I'm still on the fence. I guess my concern is installing them without removing the head. It seems like there are more people having head stud failures with the 1-by-1 method than there are people blowing gaskets on stock head bolts. This may be purely a case of people doing the install wrong, but then again there doesn't seem to be an absolute consensus on installation method, torque values, etc. I want to run about 24 psi on alky eventually.

 

Well I havent installed them and i dont have cams i run 21PSI and no problems. Is it something that will happen overtime. will you be able to tell from looking at the cylinder head? Also... Will the car start acting funny before they blow?

 

I don't think that Buschur is using them on his RS. That alone would be a testiment to the fact that they are not needed.

 

There is nothing wrong with the stock head bolts. They are torque to yield bolts so when they are installed they stretched to a certain length. You never reuse torque to yield head bolts because they are already stretched.
ARP Head studs are not designed to stretch in the same manner but some stretch is normal. They are reusable up to thier maximum length. The ARPs are probably twice as strong as the Head bolts, if not more. There is no competition because ARP does one thing and they have been doing it for quite some time. ARP has a very good reputation for their products so it would be hard for anyone to try and compete with them.

Anyone who installed ARP head studs and had one back out did not prepare the block for the studs properly. Fasteners are possibly the most important part of an engine. Most head gaskets blow because proper torque was lost in the area of failure. I wonder how many people are rebuilding these motors and reusing the main bolts. These are also torque to yield, as well as rod bolts. NEVER resue torque to yield bolts. It is just not worth it.

 

Wat he said!!