The Virgin Spring is amazing but very depressing. I did like Night Train Murders but it's a bit of a Last House On The Left rip off to be honest with similar flaws.

Another kinda gory movie is Midnight Meat Train. It's based off of one of Clive Barkers short stories.

Cutting Moments
 

You should try Doug Buck's CUTTING MOMENTS but you might need to watch it on youtube...

Love that film but doubt I would watch it again-I don't need to be reminded of why I am a veggie but if scenes in a meat packing plant don't bother you then I recommend it.

Scrapbook
Redsin Tower

I found Scrapbook quite nasty and disturbing.

Redsin Tower had some reasonable scenes, but not as gory as I would have expected.

Oh, and the Guinea Pig films (especially the 2nd for gore).

Maniac
Motel Hell (comedy horror, but still has some disturbing scenes)
Death Weekend
Ghosthouse (La Casa 3)
Stagefright (Aquarius)
Tourist Trap (same deal as Motel Hell)

I'd say try the Japanese movie 'Grotesque'. It's certainly gory, and was banned outright in the UK. There's some silly stuff going on right at the very end, but it delivers the goods all right. :D