After some trial and error and some help from the forms, I was able to figure out how to tune the ATtying2313 and get reliable serial communications. As a result I decided to design a kit that makes it much easier to tune.
The TinyISP-Tuner connects to your computer via a FTDI cable and has an ATmega328p as the controller. The ATmega328p is running the TinyISP sketch with tuning and KnockBang. KnockBang allows you to pass serial debug info via SPI over the FTDI cable to your computer. Very convenient. When tuning is enabled there is a 16ms pulse sent out to the ATtiny you are programming. Plus you can program the ATtiny once it is tuned with your sketch. All with this one kit.
Supports ATtiny84/44/24, ATtiny85/45/25, and ATtiny2313/4313.
• 1x PCB
• 1x 6pin Right Angle header for FTDI programming
• 1x Atmega328p DIP (Pre-programmed with TinyISP configured for tuning)
• 1x 16Mhz Resonator
• 2x 0.1uF Capacitor
• 1x 10K Resistor
• 1x 330Ohm Resistor
• 1x Red LED
• 1x 20pin socket
• 1x 14pin socket
• 1x 8pin socket
• 1x 28pin socket
Check out the guide: http://friedcircuits.us/docs/tinyisp-tuner/
If you want to buy one: https://www.tindie.com/products/FriedCircuits/tinyisp-tuner/