Torque requirements for aluminum crank bolts?

As per title: what are the torque requirements for old square taper aluminum crank bolts like the SRP ones? I was searching online over the weekend but I couldn't find any good info on that. I installed the cranks with steel bolts first and torqued them up to the required 40NM but when it came time to put in the alloy bolts (blue anodized Speed Metal ones NOS) I couldn't find any info in the torque settings for those. I didn't want to over-torque them and snap them off, so I put them in using 8NM of torque. Does anyone here have a good idea what a good torque setting would be for alloy bolts? I know that titanium crank bolts like the Syncros Crank-O-Matics are in the 20plus NM range but I'm certain that aluminum ones are not that high.

Leave the steel ones in if you value your shins

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Do you use any grease? In that case the given torque rate is probably too high.
I'd grease the bolts lighty and tighten them just as it feels right. If you use the right bolts it's really not necessary to turn them very tight.

I used copper anti-seize paste. The spindle is Titanium. Unfortunately I don't have a given torque rate for the alloy bolts so I went for 8NM. Aluminum chain-ring bolts have a torque range between 5-10NM so I reckoned I won't overdo it with 8 NM.

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Sounds ok. But there's quite some difference in the torque needed for tightening bolts with and without grease. So before using a torque wrench you need to know the right number, greased or not. Copper paste is ok but mostly used for area's that get hot. Vaseline will do just fine.

In The Netherlands we say "vast is vast", which just means that you use common sense and feel and never overtighten. So "tight is tight"
So maybe just forget the numbers.

In the pics below, the left bolt is dry, the right one is greased. To tighten the left as much as the right it needs 14 Nm instead of 5 Nm, so almost x3.

I'm using copper paste mainly for anti-seizing purposes, not so much for lubricating (even though I suppose it does have some lubing attributes). Mostly Ti bolts on Ti spindle should always have anti-seize (used it on the alloy bolts as more of a precaution). The problem is: I can't find anywhere a torque number for M8 alloy crank bolts (nevermind getting into the specifics as to dry or lubed) the only number I came across seemed way too high hence I was wondering if anybody on here remembers any of the (let's say SRP) recommended torque values for their bolts. Unfortunately most of those manufacturers are not around anymore...

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Every parts manual I've ready (yes some people actually read them) state torque figures for lightly greased bolts.
Can't imagine mtb components ever being quoted with dry torque figures.
Having been stupid enough to use alloy crank bolts in the past, I don't remember very high torque figures needed. You did the right thing using steel for assembly then swapping to alloy. I used to use X Lite ones, albeit on square taper. Maybe try seeing if you can find figures for those as a comparison.

No matter how much I search online. No definitive answer seems to pop up. I do have one lonely red SRP alloy bolt flopping around my tool box. I could get a shitty old cheapo BB spindle and torque the bolt up incrementally until it snaps. That would give me a rough idea where the torque limits of alloy M8 crank bolts would be. Then I'll go less from that. The question is: what percentage less? 50% of snapping torque? 75% of snapping torque?

I tried the single SRP bolt this weekend. Put a crank on a crummy old BB and started torquing from 6NM jumping up in 2 NM increments. I got up to 32 NM and the bolt has held just fine (no breakage) at 32NM my small torque wrench topped out and I was too lazy to search for the big one. Bottom line: those alloy bolts are stronger than one would give them credit. I torqued up the ones on my Ritchey to 16NM since that would be 50% of the max torque I got from the SRP bolt. I guess the bolt could have gone up to 40NM but I didn't feel like I needed to break it. That's my empirical evidence to this matter so far. Fair enough the bolts on my Ritchey are Speed Metal and not SRP but one can assume they use a similar grade of aluminum (and the Speed Metal bolts are NOS whilst the SRP was used).