Fuel Injectors maxed out? really!?!?

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Nov 13, 2013 | 10:08 PM

roastin240

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From: Melbourne, FL

Fuel Injectors maxed out? really!?!?

Mods are:

Stock LS1 longblobk, LS6 intake manifold, ported TB, 4 inch intake system, 85mm MAF, 1 5/8 in shorty headers, full exhaust w/ no cats.

When tuning in open loop, SD, no PE, the AFR is lean under WOT and peak load area. No matter how much I increase the VE I cannot get any more fueling to it. Injector Duty Cycle in HPTuners is reporting values over 100%. Is it time for me to do an injector upgrade???

Nov 14, 2013 | 06:24 AM

Old Geezer

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Post the tune and data log[s].

Nov 14, 2013 | 08:03 AM

roastin240

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Okay when I get home tonight I will log some pulls and post them. Thanks

Nov 14, 2013 | 07:59 PM

roastin240

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it will only let me upload the tune. says the .cfg file is invalid? whats the deal?

Attached Files

Johnny_Original_with gas fix 100313_rev3_GTO_VE_Open Loop VE TUNING.hpt (454.7 KB, 81 views)

Nov 25, 2013 | 08:04 PM

johnson73801

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From: woodward,ok

just a stupid question but have you checked ur fuel pressure to make sure its not weak and causing you to lean out

Nov 26, 2013 | 01:57 PM

ZL1Killa

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what injectors are you running? if you are on stock and with those mods...i can believe it easily. the stock system was not intended for much beyond stock. With the stock pump though, you can provide enough fuel for up to 8 x 32LB/hr injectors rated at 43.5psi -- ACTUALLY at our fuel pressure 37LB/hr (58psi).

FYI, what most people do, is grab the Walbro 255 pump & wiring kit (REQUIRED- TRUST ME) and usually 36# @43.5psi or 42# @43.5psi injectors and continue to mod. Only stepping into forced induction requires a Fuel pressure regulator (MAP referenced) and much larger injectors.

Nov 26, 2013 | 02:56 PM

NicD

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From: Chandler, AZ

Factory ls1 28.8 lb injectors are good to near 410-420 rwhp on a dynojet SAE which your bolt on ls1 isn't going to come near. I would say you probably have a fuel pressure problem so put a gauge on it and see what it shows at WOT in the higher rpms.