I think I understand why my RPM values didn't mean anything... I had accidentally set up my received filter on the LPC11C14 to receive EVERYTHING. oops.

In order to aid in debugging - I had an idea - why not get a serial stream of data going? I can use an HC-05 bluetooth module to connect my phone to the CAN-obd2 board :). 

Check it - You can see that I bodged it in there really well. I'll rest it on that piece of red Duck-tape (yes Duck tape brand - deal with it).

Oh yeah, I forgot to mention that I put an el-cheapo pot on the contrast adjust of the LCD:

Here's another closeup of the bluetooth connections:

I added code to the boot-up function of the LPC11C14 to tell the HC-05 in AT mode to speak at 115200 baud. 9600 is too damn slow.