Thread: Headstud comparison

Same design...and I have tested them up to 30psi with a PT74 and everything tested out great...and I have BEAT my car...hands down.

If ARP's where sh*t so to speak...then how in the hell have all my motors and everyone elses running 1000+hp stayed together? Lol

i popped headgaskets twice on my vet. the car was sitting at around 470whp at 24lbs. the first time i thought it was the cometic hg. but couldnt find anything that showed where it blew out. never did i think about what was really happening. the second time i used a stock 20V steel hg. it held but then it happened again. pulled the head and it appeared that nothing blew the gasket into a water passage. just there was water everywhere. after seeing matt's greddy bolts in person, i then realized on why the arp's are ****, and that under hard boost the head was actually lifting, that since the arp's only lockon to the first two threads in the block,... that when a great amount of psi is in the combustion chamber... those two threads give a little.... a little enough for the headgasket not to seal.

Locks on to two threads? Lol bro something was really messed up here. Period.

ill say it again. the arps are a ****ty disign. there is no in between..there is no right in saying ill use them since im staying under a level of horsepower. they were not engineered properly.

How do you figure this? Any charts for compression under stress test on why they are sh*tty?

at this point ill take my chance with 1/2 inch head studs, or the old school...factory head bolts.

Factory over ARP...explain please?

here is another expierence i have had to back up that they are designed wrong. when you install arp's they tell you to install them, but not at all to tighten them. this means that when you go to take them out (one of a few reasons)... they should just screw out. nope they dont. not at all. you damn near have to vice-grip them to get them out. why? becuase they are now locked onto the top few threads in the block, from tightening the nuts when the head was installed.

The reason that you only do them hand tight is because the studs stretch a certain amount based on ARP torques spec. With a shank stud its solid, has not stretch no force. The only force you have is that of the torque you apply. When them stretching that is why they have you torque PAST your factory specs. With the pressure applied it applies a "clamp" type style. Which is by far superior than that of a standard stud.

Also, remember that they ALWAYS suggest to retorque after the engine had been ran and warmed up. This is a MUST with all of ARP's head studs.

^^^I agree. Retorque all studs after a few miles.

Some people get lucky and don't retorque and their cars are fine. However I have seen a handful of cars go down because of this. The first question I ask is, "Are you using ARP studs"...they say, "Yeah, why"..."Did you retorque them?"...I get this answer every time..."No, why should I? I torqued them past factory specs and if factory bolts can hold at that this surely can"...FAIL incorrect.

They can't...because of the compounds they are made of you should ALWAYS give them another shot. When I did mine after my first crank I got a pretty good move on them...I even went back and double checked after the first oil change after my build...guess what...SOLID. So it showed that had I not torqued them back down...they wouldn't be where they are today.

All your motors and eveyone elses running 1000+hp, you say that like a ish load of sr20's are 1000+ hp. We are not saying that APR's are no good, simply that they are no good for the sr20, IIRC they were originally designed for the L20 or maybe VW motor and they found they also "worked" on sr20's.

And if Mazworx, who is at the forefront of sr20 building in America, decided to make a 1/2" stud kit for there 40+psi 1000+hp motors, I think it was probably for a reason.

PS- it takes more then 30+ psi to get 1k hp as you must know since your motor pushes over 1k hp.

I never said MY motor pushed over 1000hp...I stated my psi kthxbye

^He never said his car pushed over 1k............We were some MODS from reahcing that goal, but it would have held up.......Like I stated before, the only thing we had concerns about was the tranny in the early going of the car. The ARP studs were not on the list.

He has a article on his car with the dyno if you would like to see what the car really made. I will let him post it if he feels the need, or you can check it out in "Super Street Readers Rides" 5/08 issure....It is a black IS300 with a T74.

kthxbye... osunds like a 12 year old girl texting

any way this statement

makes it sound like you and all the other 1000hp motors you know of are fine with ARP's. Making it sound as though your motor is lumped into the 1k hp group.

I am not here to bicker with you, but do you work for ARP or something? I mean many people have the same prob, some is user error, but stereo types are for a reason right?

OEM are good for a lot of power, and if you dont want to risk your motor on them because of your power level then $335 for the GReddy are a steal, or $560 for the Mazworx 1/2" service is great when your at that level.

On another note if GReddy made a stud kit for gtir I would buy them, but looks like I gotta do JUN since sourcing the OEM head bolts is a whore.

You have 12 year old girls texting you? <----assumption...

Sorry, I should had stated it more clear in my sentence. I do not work for them, however I do have a close connection with a few of their main clients. I wouldn't use something nor would I suggest it if it didn't work. I have been using and suggestion these to friends, clients, and people on boards since I have turned my first wrench on a car. However you sir if I am not mistaken just over a year ago you had planned on ordering a set of arp and even suggested to someone else to buy arp. So what experience did you have that was good or bad that caused you to sway away from them in a years time?

Don't care what his car made, we all have dyno charts.
I hope you all reach your goals of 1k hp with minimal issues, I love motorsport as much as you all I am sure.
But ARP sr20 head studs are not some design flaw myth, and simply blaming it on all the users who have had a problem is not cool, especially when the company openly admits a design flaw is present and anyone with eyes can see that only a few threads are used.

I planned on oredering them fro my s13 a while back when I was on Freshalloy a lot as I belived they could not be as bad as they were nade out to be until I istalled some with my bud in his sr20 and saw for myself the length of the stud and how it did not engage the thread enough and decided not to risk it and went with OEM.

Jeremy