Bathroom waste/vent piping [PICTURE]

I am remodeling my bathroom. Is this an acceptable way to do the waste/vent?

No.

the lav is not vented
The shower is not vented
The lav and the shower p-traps will siphon every time the toilet is flushed.

Helpful Plumbing Hints for Residential Construction by Bert Polk Plumbing Inspector Lincoln County

It's a good thing people do not try to be their own doctors or lawyers, or those professions would be in a world of hurt. But EVERYONE wants to be a plumber, because all you have to do is "put a few pieces of pipe and fittings together and the job is done". Your drawing does NOT vent the most important fixtures, the ones that really need them.

How about this?

Lav is still not vented. You could normally connect the lav with a santee and bring a separate 1.5" vent off the top to vent it. You might also be able to arrange things and "wet vent" through the lav and have a single vent to vent the entire bathroom group. You have to see what plumbing code you are under and what is allowed. For instance, some codes require the vent for a toilet to be within a certain distance and others allow an unlimited distance to the vent for a toilet. There are also requirements on how far the vents for the other fixtures and be from their vents and these distances change depending on what code you are under.

I also strongly recommend getting a permit and having this inspected. This a good 2nd check to make sure you have things correct and legal. Many people try to bypass inspections/permits to save $$, but that is really a bad idea in my opinion. It is worth a few bucks to make sure it is correct and legal.

sorry nukeman, i think i changed my picture while you were replying. Is the picture above your reply correct now? The lav and shower are both vented and the WC is wet vented through the 3" upstream to the 2" dry vent. Correct?

Bring in the shower on the other side of the toilet with a wye fitting. A proper vent is downstream, not upstream.