Originally Posted by Flat 4 Motorsport
Hmm, not understanding why the industry standard is heptane, when gasoline is what's being used primarily.
Can you shed some light?
Probably as luke said, it's a well defined chemical compound, but does it really matter? What matters is that if you're comparing, you compare the same injectors on the same fluid.
Here is a Bosch EV .pdf:
Bosch fuel injectors have their flow rates defined in N-Heptane as part of their engineering specification. N-Heptane is a pure
chemical and does not have the same viscosity and density as standard petrol. Hence the N-Heptane flow rate figures stated
should be used as a general guide for comparison purposes only.
The use of the term "'pure chemical" implies that Luke is correct, consistency of the fluid is the primary factor, but they don't come out and say it.
The N-heptane flow numbers are closer to the ECU scalar than the gasoline flow numbers.
I suspect there isn't a HUGE range of flows across brands offering the EV14, but I bet the different injectior tip designs do result in some small and repeatable differences between brands.
In general the EV14 "1000-ish" cc injectors will flow less than the 1000-ish cc Denso designs, but there's a reason Deatchwerks started carrying an EV14 in the same flow range as their 1000cc Denso design... They had feedback from tuners that the EV14 is a substantially more consistent and better behaved injector at those flows.