Fuel injector length. Noob question.
 

When I took apart my 01' to do the turbo install I did not notice the small spacers between the manifold and the fuel rail and so when I found them I had no idea what they were and so, I didn't reinstall them when putting in the rx7 460cc injectors.

When I put the rail on, I torqued the bolt down and just guesstimated what was the proper amount and went with it.

I removed the injectors in preparation for installing ID1000s and noticed that the rubber seal on the bottom of one of the injectors was damaged, and that likey happened when twisting the injectors (while torqued) so that the plugs were accessible. I won't do it that way again.

However, I notice that the stock injectors are .2" shorter than the ID1000s. It seems to me that I should have a spacer, but the original ones are missing and it appears that they would be too short anyhow.

Can I use standard washers, or do they need to by non conductive? What is the proper way to solve this problem?

Proper way is go to the Mazda dealer and buy new ones.

But that doesn't account for the length. Just double them up?

If the ID's are longer and you didn't use the spacers (I don't understand how this even worked) with the rx7's, you'll need then with the ID's.