replacing head studs

[allballsmustang]

I'm currently running gt40p's with ARP head bolts and 6psi of boost. I will so be increasing the boost level. I was told that I should look into replacing them with head studs instead. I was hoping to be able to replace one at a time so I wouldn't have to pull heads and replace the head gaskets. Has anyone done this before? Thanks,

Jim

 

[Rick 91GT]

You can get away with that, Id drain the block however to make sure you can get the threads clear of all fluid. Easiest way is pull one of the plugs on each side of the block out that is in the coolant passage.

Start at the outside bolts and go in a "x" pattern on the head to prevent warping. All lower studs need teflon or Permatex on the threads that enter the block coolant passages. The upper bolts just get moly lube on the threads, TQ the upper "longer studs" 5 lbs more then the lower

 

[allballsmustang]

i must be a little dumb, what is the resoning for the oil drain? Do the oil passages actually go into the threaded holes for the studs somehow? Which plugs on the block are you referring to for draining? Also whats the reasoning for the higher torque of the upper bolts? Lastly, do you think that this upgrade is necesasry or overkill? Thanks a lot.

Jim

 

[BlownFiveLiter]

Rick actually means coolant. The lower studs pass through the water jacket.

 

[Rick 91GT]

Correct the lower bolts/studs enter cooling passages on the plug, the drain plugs are 1/8"NPT pipe plugs on the side of the engine block, they can be tricky to get to in the car but it's possible. Otherwise, pull the lower radiator hose and drain it down as much as possible.

With boosted set-ups or high compression set-ups it is better to TQ the longer studs a few extra footpounds for added clamp load.

As far as a worthy upgrade? Well studs have better clamping power but you could run bolts all day long in that set-up if you wanted to. I'd wait till you pop a headgasket or have to pull the head for a reason and then upgrade.

 

[allballsmustang]

thats kinda what i was thinking. I think ill just pull the valve covers and check the torque to make sure nothing loosened up and then ill just get a new set when the heads come back off. Ill probably be upgrading heads within a year or so unless i blow her apart sooner. LOL Thanks for the info Rick.

Jim