head studs? Whats the best?

[Mike Neal!]

Where do I find TQ specs for the ARP's? I wonder if mine could just be re TQ'd?

[mike55112]

I beleive there 85 ft lbs.

[Shane@DBPerformance]

He doesn't know much about his motor, he bought the car modded. He is running running over 30psi of boost. He isn't knocking.

Pushing coolant under high boost, high load, higher power is common with the DSM heads even with no knock/detonation. They are not as rigid as the Evo heads and are prone to flexing easier. L19/H11 head studs and good headgasket usually fixes this and sometimes even when you just slap them in like Brad did. The Mistu MLS gasket for DSM is not all that good, the Evo MLS is very good. I personally think that normal ARP head studs might be worse than stock head bolts, but I could be wrong. If they are better, they don't seem to help much at all.

When the head lifts on a DSM under high load, you push coolant and it goes back down and all is fine until you boost again and push more coolant, or you push enough to get a big air pocket and start overheating, or you warp your exhaust valve seats from doing it too much. You don't want to fill up your coolant overflow and have it overflow onto your tires though at 100mph. When your head lifts on an Evo it likes to blow freeze plugs out of your waterpump or block, makes a big mess.

[TalonFiero]

30+psi for 50K miles on my stock HG and stock head bolts so far in the evo. no "Knock on wood"-alcohol!

[Kracka]

Where do I find TQ specs for the ARP's? I wonder if mine could just be re TQ'd?
ARP's are TTY (torque to yield) studs meaning they're designed to be torqued/stretched once and NOT reused unlike popular opinion states.

[Shane@DBPerformance]

ARP's might be one time use studs, but I don't think they are TTY.

[4seasons69]

I beleive there 85 ft lbs.

it's around 80 or 85 with moly lube and 120 with 30wt oil

ARP's might be one time use studs, but I don't think they are TTY.

I've looked around a bunch and haven't found any legit info on them actually being tty. I've looked on arp's site and other forums and all I've found is people saying they are tty nothing from the actual manufacturer sayin they are tty. Infact i've found more info saying you can reuse them if they are NOT stretched. I've even found posts where they talking to the arp people and they said they were reuseable if they are not stretched

I think half the problem is people over torque them and when you stretch a bolt too much it loses a lot of it's clamping ability.
so you have a weakend headstud in an engine making a lot of power and the head lifts and you push coolant. correct me if I'm wrong but thats just my thoughts on it.

on another note I'm running arp's and a commetic hg and haven't pushed any coolant since I've put them in almost a year ago, even on the dyno when I had it tuned on a spike to 25psi then settling to 21psi and making 280awhp at db. ( but I know i'm not making a ton of power so we'll see how things hold up).

[blackrosenova400]

I dont know if I agree on this, are you sure these high load conditions arent causing alot of thermal expansion of the coolant? Its what it sounds like to me, because if you raise your head far enough to move combustion into the coolant, your headgasket is junk.






He doesn't know much about his motor, he bought the car modded. He is running running over 30psi of boost. He isn't knocking.

Pushing coolant under high boost, high load, higher power is common with the DSM heads even with no knock/detonation. They are not as rigid as the Evo heads and are prone to flexing easier. L19/H11 head studs and good headgasket usually fixes this and sometimes even when you just slap them in like Brad did. The Mistu MLS gasket for DSM is not all that good, the Evo MLS is very good. I personally think that normal ARP head studs might be worse than stock head bolts, but I could be wrong. If they are better, they don't seem to help much at all.

When the head lifts on a DSM under high load, you push coolant and it goes back down and all is fine until you boost again and push more coolant, or you push enough to get a big air pocket and start overheating, or you warp your exhaust valve seats from doing it too much. You don't want to fill up your coolant overflow and have it overflow onto your tires though at 100mph. When your head lifts on an Evo it likes to blow freeze plugs out of your waterpump or block, makes a big mess.

[v8klla]

Best headstuds out there are A1's. Shep, Rau and others use them. But, they are quite expensive...usually they cost around 600-660 a set.

Times have changed my friend ;)

A1 Technologies H11 / L19 6 Bolt Head Studs $254.99 (http://www.maperformance.com/a1-technologies-h11-l19-extreme-duty-head-studs-6-bolt.html)

[Mike Neal!]

Motor blew up tonight.. :( weak.. now on to 2.4 I guess