The nosmod.zip file you have requested: Modifications / Ultimate Nos Mod - 192.33kb is not available. Perhaps try browsing all files for the game Grand Theft Auto: San Andreas and upload any files you want to share or are missing. This is the only information we could locate:
Here is a mod that has 5 different effects for Nitros (I think?, since the readme is in German). To add these to the game, move one of the "Effects.fpx" to the Models Folder within GTA: San Andreas, and these effects should show when you use them. This is a highly recommended mod.