Originally Posted by Fuel Injector Clinic
We did offer 1680s previously but they have a higher sensitivity to fuel temperature and in certain setups there running higher than normal fuel temperatures the injectors were responding in a less than ideal way. They did work great in many cars but due to the issues we saw in some of these examples we decided to stick with the injectors that work well in all conditions and we removed these from our list of applications.
We have had great success running the 1100cc injectors at higher fuel pressures though, which raises their effective flow rate if you need a bit more than the 1100cc injectors can offer at 43.5 psi of base fuel pressure.
For example, if you run these injectors at 60 psi of base fuel pressure then they flow nearly 1300cc which is about a 20% increase in flow, and allows them to support quite a bit more power.
So long as you have the fuel pump(s) to support the higher pressures then this is a very nice solution for some people. If you're not familiar with going down this path and have any other questions just let me know.
Do you have an idea of how much wheel horsepower you expect to be able to make with your setup on E85? That will help me determine and ideal injector size for you.
Thanks for the helpful response. I also sent a pm.