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Injector Duty Cycle at 97% with (almost) unmodified 'Heartbeat' SC >
EDITED POST >
Well, my 2011 GS / A6 is not completely unmodified since I do have a set of headers on the engine and a Kenne Bell BAP set to 4 PSI ... However, the 'Heartbeat' SC is installed just as it came out of the box except for a slightly smaller 93mm drive pulley ... Harmonic balancer is stock diameter.
The car dyno'd at a conservative 535 RWHP @ 6,300 RPM.
Using the LS9 / Bosch # 0280158187 fuel injectors (52 Lb / Hr @ 58 PSI) that came with the Heartbeat SC, the tuner told me that my injector duty cycle was as high as 97% during the dyno pull (AFR was steady at 11.6 - 1 throughout the pull) ... Boost pressure was pretty steady at 7 1/2 PSI during the last half of the pull as shown on the HPTuners software.
My question ... Could / Should my injector duty cycle get as high as 97% in my current setup / HP level ??
When I first put my eforce on with those injectors I don't think the duty cycle was that high... but that is not really relevant. If the log says it its, then it is......
All he said was that if I increase the HP up in the future, I might think seriously about a set of slightly larger injectors.
I just thought that at my level, the supplied injectors would more than likely be operating at closer to maybe 85% duty cycle or less ... of course, what do I know
That IDC sounds about right, albeit maybe a little bit high. The LS9 injectors that come with the Heartbeat don’t leave much headroom for increased power. With the 90mm pulley/stock balancer setup with the stock cam, with boost right at 8.4psi, I was seeing ~95% at ~6500. Below is a snapshot of an old datalog of that combo with it at 6100 with the IDC at 93.5%. I don’t know what the AFR actually was on that run because it was either not connected or not working.
That almost looks too smooth. What's with the dip at 5800?
My tuner (Howard Tanner) said that dip in both the HP and TQ at about 5,900 RPM was more than likely the rear tires jumping on the rollers ... no concern
Thought you would have had more head room on the duty cycle of the supplied injectors that came with kit.keep an eye on A/F when in boost.enjoy the power
My tuner (Howard Tanner) said that dip in both the HP and TQ at about 5,900 RPM was more than likely the rear tires jumping on the rollers ... no concern
11-29-2018, 10:26 AM
Injector Duty Cycle at 97% with (almost) unmodified 'Heartbeat' SC >
