Re-torquing ARP headstuds

[sleepydsm]

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.

[Halon]

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.

[scheides]

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

[FattyBoomBatty]

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.

[Halon]

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.

[scheides]

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

[Halon]

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?

[niterydr]

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?

Correct.

[scheides]

Read from like the 3rd page on of the link I posted. Also when you do the copper spray you need to do it VERY evenly and you can easily over spray in some area's making the surface uneven.

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?

[FattyBoomBatty]

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