INjector Guide

[firehawk]

Wow, it seems that the bigport 4A-GE injectors are a pretty "close fit", as according to this formula it seems that 192cc/min injectors at 3kg/cm2 fuel pressure need to run up to 82% duty cycle ("brake specific" value set to 0.475) to produce 124hp.

This means that pretty much any performance upgrade would require at least larger injectors and quite possibly an ECU remap (or a piggyback) to get mixtures set up correctly in idle and partial throttle.

Using the same values for max. duty cycle and "brake specific", with the 250cc/min redtop injectors and stock FPR, the engine could go up to 162hp.

The TRD Levin&Trueno Bible says that the gr.A AE86 used 250cc/min injectors and the dyno plot shows the engine doing 170hp, so the TRD ECU must run the injectors quite to the limit - up to 86% duty cycle, apparently.