Re-torquing ARP headstuds

[jrohner]

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

[Shane@DBPerformance]

...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.

[scheides]

Maybe its time for direct port meth injection?

...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.

[Pushit2.0]

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

[FattyBoomBatty]

Originally Posted by ecoli

...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.

Snap, yet another reason the starquest is superior.

[scheides]

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.

[scheides]

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.

[1QUICK4]

ARP spec is 80 with Moly Lube

[scheides]

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

[Pushit2.0]

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

[scheides]

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.

[Archertsi]

Originally Posted by ecoli

Heres how you do it... Buy some L19s from me, remove the head, put in a new HG without copper spray, and torque to spec.

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 . . .

[FattyBoomBatty]

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.