Did a little digging and I didn't find definitive info, here's some stuff that may help.

Here's an older thread talking about the early key blanks with some pics:

http://www.classiczcars.com/forums/help-me/12182-ignition-lock.html

Here's a snipped from the parts fiche showing the different key blanks:

Datsun 240Z/260Z/280Z Blank Key

It appears that the very early cars had single cut keys with grooves on one side only. There were multiple different key blanks for these early locks. You don't have this style and I don't know much about them.

Then at some time, they switched to the reversible key type that was cut on both sides which doesn't matter which way you insert it into the locks. This is what you have. On the parts fiche, it indicates that these reversible styles came in "left" and "right". I'm thinking that there might only be two versions of your blank, L and R.

And as a side note, I can't get sections seven or eight of the parts fiche at xenons30.com to work. Is it just me, or is there something wrong with them?

It isn't just you I can't get them to load either. Section 6 loads, I didn't check the others.

I hate when that happens.

!

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Then at some time, they switched to the reversible key type that was cut on both sides which doesn't matter which way you insert it into the locks. This is what you have. On the parts fiche, it indicates that these reversible styles came in "left" and "right". I'm thinking that there might only be two versions of your blank, L and R.

Thank you! That jives with what I've been told by my locksmith. The trick is figuring whether a given lock set was "left" or "right", which none of the parts places seemed able to tell me. Can't blame them - knowing every nuance and detail of every part carried is an unrealistic expectation.

My locksmith was able to tell me that I need a C-16-116, which happens to be one that I stumbled across yesterday on eBay so I grabbed that one for a reasonable $18. It should be here this week and we'll see if it can be re-keyed properly. If that does the trick then the whole situation is really pretty simple, but was made complicated by the various key types that I wasn't aware of going in. Hopefully this info will be helpful to someone in the future.

It isn't just you I can't get them to load either. Section 6 loads, I didn't check the others.

I messed around a little and based on the pattern of URL's they used for the sections, I've verified that section 7 is there. It's just not linked to correctly. If you enter the address manually:

You can get to section 7 here

Section 8, however, is truly MIA. (Maybe because it's "Section 8?")

The trick is figuring whether a given lock set was "left" or "right", which none of the parts places seemed able to tell me. Can't blame them - knowing every nuance and detail of every part carried is an unrealistic expectation.

You don't need your locksmith to tell you if it can be reyeked... You'll know as soon as you try to insert your blank. If your blank slips in, you should be able to key it to what you need. If your blank won't go in at all, you're still on the hunt for the correct one.

Fingers crossed for you!

Another option I just thought about if you get desperate. You could use the longer cylinder (the one with seven tumblers) and just not populate all the positions. Just put six tumblers in it and it will operate just like the shorter cylinder. Locksmith will probably hate that idea...

Only thing is that I'm not sure a longer cylinder will fit properly in the housing designed for the shorter one. Just musing at this point.

Section 8, however, is truly MIA. (Maybe because it's "Section 8?")

Ha Ha that is pretty good.

Being ever curious about computer graphics I noticed the fiche classiczcars.com sells in the store is more readable than the one at the xenons website though I think it is great xenons offers their fiche as a free service. I only noticed because I was recently looking up a part and was trying to read part numbers:

Fiche on left from

classiczcars.com:

On my old car I took the hatch lock apart and rearranged the order of those tumblers to make the ignition key fit though the keyway has to be the same for this idea to work. I did have to leave one tumbler out as it would not fit the key no matter what position I put it in.

Edited June 14, 201311 yr by Mikes Z car

Well I got everything straightened out! Although the locksmith wasn't able to source a replacement cylinder for me, he could tell me the specific p/n I needed to go with my key (C-16-116) and I found a NOS part on eBay for $15 (at least this stuff is fairly cheap). $40 to re-key and install it in my steering lock and I'm good to go.

Now if only I hadn't started disassembling the front suspension and interior, I could actually try it out. In good time...

Thanks for all the info, I wouldn't have realized all the cylinder options if not for you guys.

Awesome. So you should be all set until your door locks start acting up. :laugh: