couple misc questions

[Tictakman]

might have been answered but was unsure about them.

i pulled out my exhaust head studs and bought some new ones at auto zone. they are not exactly the same lenght but i dont think thats an issue. what should i tighten them down to into the head? i have a fsm but it doesnt give a torque spec for the actual stud, it give it for the nut that hold the mani on.

also, im putting in a a/f gauge, on my kat it wasnt a issue with what wire bc it was only one. what wire do i splice into on this o2 sensor?

last question: im running a dual flexilite fan setup and wanted to know where everone is putting the sensor probe, i tried tightening it into the radiator but the seal isnt there and its leaking without any pressure so i know it will leak when i start it up. should i attach it to the outside of the radiator?

thanks

Zak

[StricNyne]

for the af gauge, i tapped right by the ecu its one wire i think purple, look at an ecu pin out

[Tictakman]

damn i didnt even think of that, guess that will be one less wire in the engine bay...

Z

[Darius]

When i replaced my head studs, they were just hand tightened and then the nut was tightened to the torque spec depending on if you used moly lube or not.

[Tictakman]

do you get any exhaust leaks with just hand tightening them? i will look at it tomorrow!

Zak

[armysweitzer]

i put 2 bolts on them and tightened them into the engine, then carefully took them off without loosening the stud. taking a physics look at it i dont think they have to be super tight into the engine as long as there tight on the manifold. I mean equal pressure on 12 or so (forget how many) bolts will hold a lot of strength.

PS i used copper super temp gasket maker for the manifold and its a great seal. Its rated for like 1800 degrees or something like that.

[Darius]

It is not the physical torque tightness that determines the pressure that the bolt exerts. It is the pulling force the nut exerts on the bolt while effectively prying the exhaust header towards the head that creates a sealing effect. Basically puts the head stud in tension.

Hand tightening is really all you need, then torque the nuts onto the studs per the specified torque.

Can anyone tell that I'm at work writing specifications??? Who says "per specified torque"? What a geek.