When I made the initial decision to run E85 (see post here) I was aware that everything in the fuel system needed to be E85 compatible and that I needed to add an ethanol content sensor. I subsequentially learned that E85 contains 40% less BTUs than gas which means that the system must flow more. Since E85 is 85% ethanol and 15% gas that equates to (0.85*1.40) + (0.15*1.00) = 1.34 or 34% more volume. E85 also increases power, so the Wide-Open-Throttle (WOT) demand is even higher. Based on this information, I upgraded the low-pressure pump and chose an appropriate high-pressure pump. Problem solved, right? Nope.
What I failed to intuit is that what goes in must come out through the fuel injectors so I need to upgrade them. Everyone that I spoke with recommended the Injector Dynamics ID1700x for my application. The tuners love them because they supply accurate detailed data which simplifies their job and results in excellent tunes. Apparently one supplier stole their data, fudged it and presented it as their own (thread here).
While other suppliers modify stock Bosch injectors, Injector Dynamics is the only aftermarket supplier to have earned Bosch’s Authorized Technical Partner status under which Bosch Motorsport manufactures Injector Dynamics’ proprietary design. Injector Dynamics then breaks them in for a few hours and groups them into matched sets.
They’re very trick, but at $300+ a pop a set costs almost a quarter of a fully-dressed LS3 crate engine. That said, the upgrade was simple. I just removed the fuel rails, lubricated the O-rings with WD40 and popped them in.
OEM fuel injector (left) and Injector Dynamics ID1700x (right)
I’m not crazy about the purple aluminum bodies, but unless you shine a light on them they aren’t all that noticeable