Re: Re-torquing ARP headstuds
 

IDK, 400whp is about my limit w/o building the motor, and I don't really plan on doing much more than where I'm at.

Damn it shane, really?

Re: Re-torquing ARP headstuds
 

L19's! L19's! L19's! L19's!

Re: Re-torquing ARP headstuds
 

Yeah it helped to keep the heads from lifting, which was actually the failure, not the clamping force of the studs. The difference between 78 to 95 to 110lb/tq was huge.

Chris,

I'd say if you are already pushing coolant you won't stop it. The "path" has been found and it is exponentially weaker now. I would suggest to pull it apart, make sure your surface roughness value of the block and the head is what your head calls for, and put it back together. Typically ARP rates their fasteners at 75% yield strength.

Or go with a stronger (higher tensile strength) head stud.

Re: Re-torquing ARP headstuds
 

How is surface roughness measured?

Re: Re-torquing ARP headstuds
 

With a RA tester. Go to a machine shop and they should have one. They arent cheap so they might be hard to find one. The shop I work 4 has them and they are $2000+.

Re: Re-torquing ARP headstuds
 

Also, I bought the ARPs as 'the last set I'll ever need' and now look what happened. Why should I waste my time and $$ on these L19's?

Shane, what headstuds were in that 700whp evo?

Re: Re-torquing ARP headstuds
 

Is this something mobile? I mean not like I'm gonna wheel the car down there....

Re: Re-torquing ARP headstuds
 

OK keeping that mindset, why waste time and $$ on more of the same ones your having problems with right now?

You have all the info at your finger tips, it's your call dude.

Re: Re-torquing ARP headstuds
 

AMS L19s. Same as Titan, A1, etc.

Cometic headgasket. No ghetto copper spray. No O-rings.

Re: Re-torquing ARP headstuds
 

Yes it is mobile, fairly small actually. You can google it (not many results, but they are there, pics I mean)
Here is a link to a pic:
http://pracownia.mechaniki.com.pl/in...osciomierz.jpg
they come in all shapes and sizes.

Re: Re-torquing ARP headstuds
 

Wtf does surface roughness matter? Isn't the important thing FLATNESS?

I really don't think copper spray is the devil, either.

If/when I build an engine I'm gonna be surface grinding my deck surfaces down to the .0001" muahaha. I'm going for flat as flat can be.

Re: Re-torquing ARP headstuds
 

My understanding is that flatness is very important. As far as RA goes, if you are running a composite type gasket, a rougher RA could work, but if you are running any sort of MLS gasket, then RA is important as well.

Re: Re-torquing ARP headstuds
 

Anyone local have access to one of these? Anyone mobile that could help me check flatness on the block?

Re: Re-torquing ARP headstuds
 

Well, what will you honestly do to the block? I don't think it's been out, so I doubt there are any real problems with it. RA must be good enough for the factory, so I'd only worry about the head. Just check the block with a straight edge, not for roughness.

Re: Re-torquing ARP headstuds
 

My roommate has one of those certified straight edges. That's what I'm going to use to check my block's flatness when I have the head off.

Re: Re-torquing ARP headstuds
 

orly! perhaps I could borrow it for an afternoon sometime? :D

Re: Re-torquing ARP headstuds
 

I can ask him. I'm not really sure exactly what to do though. I think just lay it on the block in as many different ways as you can, and I suppose use some feeler gauges or something to measure any gaps you find?

Re: Re-torquing ARP headstuds
 

Correct.

Re: Re-torquing ARP headstuds
 

Ok, finally read through that entire thread, no discussion of copper/no copper, but I think I want to go no copper this time around.

The head studs will get replaced no matter what, but there is a tipping point for deciding between a new set of standard ARPs and the L19s: ultimately, my goals are around 400whp (dyno dynamics). Yup, so I'm pretty much there now and happy. The safe limit of the stock bottom end is around 420whp. Let's say I get the head ported while it's off, install it with L19's and get retuned and make a peachy 425whp. If for some reason the same conditions are met in which I lifted the head in the first place, and the L19's hold, what will happen? Will the bottom-end take it? Will I much rod bearings? Will I blow a hole in my block?

Re: Re-torquing ARP headstuds
 

I doubt it. Because if it's tuned right, it should be fine.

Re: Re-torquing ARP headstuds
 

Maybe you have a spot in your timing map that's just a little too aggressive if your head gasket went out that fast.

Re: Re-torquing ARP headstuds
 

...or the meth not working quite right sometimes or the fact that meth isn't going to give even fuel disbursement to all of the cylinders since it's a single injection port and Evos don't have a "wet" style intake manifold like a carburated car does.

Re: Re-torquing ARP headstuds
 

Maybe its time for direct port meth injection? :D

...or just a second jet further down the intake tract :)

The first time I blew the HG was actually on E85, no knock, pretty safe tune.

Re: Re-torquing ARP headstuds
 

avoid detonation and your head gasket should stay sealed. We have an RA tester at work and I can loan you a snap-on straight edge and feeler gauges if you want to check the block.

~John

Re: Re-torquing ARP headstuds
 

Snap, yet another reason the starquest is superior.

Re: Re-torquing ARP headstuds
 

Ok, I ripped off the valve cover after work and then went to dinner/movie/etc with anna, her sister, and mother-in-law. The car was 100% cold when I got home, so I hit the ARPs with the torque wrench. First, 70lb-ft to see if any were loose. One nut seemed to move a smidge, perhaps half a smidge. Next, 80. That nut, and perhaps 2 others moved a teensy smidge. Next, 88. two nuts moved probably almost 1/10th of a turn and one turned a bit more, closer to 2/10ths. Doesn't seem like much, but when the two center ones are freaking rock solid at all torque specs, any others budging at all is notable IMHO. Sat and contemplated upping it to 90 or 92, but just couldn't bring myself to do it. If one of these studs breaks, the car could be down for several weeks or a month.

I've been hitting it w/o the alky on pretty good this week with little issue, saw coolant once. I'll flip the switch on tomorrow and see how much it dumps out, then back to straight 92/93 octane and low boost.

Re: Re-torquing ARP headstuds
 

Oh, another thing, I checked my notes and I'm 90% sure on initial install I torqued to 83 lb-ft. ARP spec is something redonk low with moly lube, like 71, and it seems the general public shoots for 80-85.

Re: Re-torquing ARP headstuds
 

ARP spec is 80 with Moly Lube

Re: Re-torquing ARP headstuds
 

I just want to clarify because 80 is widely stated on the internet, but if you look it up, you'll find this (unless I suck at life, which is *generally* the case):

The 'standard' bolts for the 1994+ 4G63 are model #207-4202

Page 24 of ARP's catalog (http://video.arp-bolts.com/catalog/ARPCatalog.pdf)

11mm stud, 190,000/200,000 tensile strength:
Torque w/ 30weight oil: 90
Torque w/ ARP Moly: 71

Re: Re-torquing ARP headstuds
 

If I recall they set the torque spec at 75% yield strength. That is why you can torque them more with out breaking the bolt.

~John

Re: Re-torquing ARP headstuds
 

Update, just as we suspected, re-torquing did nothing. The car runs really good and solid on 24psi pump gas tune, so I'll just leave the alky off and boost down while I get stuff together for doing the HG again.

Thanks a ton for all the advice guys.

Re: Re-torquing ARP headstuds
 

I second that!


Also, how old is your coolant cap? I had a friend with a 2g that would push the coolant into the over flow at 24psi with an fp green. We swapped to L19's and fel pro head gasket and still, it would push coolant.

Installed a coolant cap from Nissan 300zx, problem solved. I think the coolant was being heated and expanded so quickly that it was making pressure and pushing the old, worn-out cap open.

Just a thought . . .

Re: Re-torquing ARP headstuds
 

Well, that's what happened to mine at the dyno day, it wasn't fully warmed up and I was romping on it and it got pushed open by the rush of coolant.