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FS better injectors for LT1s

7838 Views 32 Replies 15 Participants Last post by  blueallie
As you probably know, the stock injectors are prone to failure from ethanol exposure. But so are many of the common LT1 swap injectors. And try finding the correct short pulse adders and voltage offsets to make these work properly at low pulsewidths. Furthermore, at the GM design limit of 80% duty cycle, the stock injectors at stock pressure only support 290hp on E10, or 325hp if you're willing to push them to 90%. Or if you buy an adjustable fuel pressure regulator and up it to 58psi, you can support 335hp at 80%, or 385hp at 90% duty cycle. But you'll still have failures due to ethanol.

Other articles discussing the problems with our stock injectors are:
  1. Mr. Injector's comments on Rochester Multec injectors
  2. GM TSB on injector cleaning susceptibility to solvents

I have a few sets of much newer (2016 Model Year) injectors available:
  • NEW for 2022 - LS PCM data available for Torqhead/ EFI Connection / 24x / HP tuners.
  • NEW for May 2021 - I'm including the four fuel rail o-rings with all injector shipments so you can have peace of mind with ALL new o-rings protecting your ride from fire hazards! (109, 110x2, 112)
  • 30 years newer design.
  • Ethanol proof, E85 friendly.
  • Vastly improved spray pattern.
  • Better starting, idling and part throttle drivability.
  • Up to 10% better fuel consumption than your stockers.
  • 36lb/hr flow rate at 43.5psi (stock is 24), or 41.6 at LS pressure (58 psi).
  • How much HP can they support? At 43.5psi and a BSFC of 0.55:
    • 415hp at 80% duty cycle, (GM policy specifies no more than 80% duty cycle to avoid overheating the coil windings)
    • 430hp at 83% duty cycle,
    • 467hp at 90% duty cycle.
  • If you use a different regulator and pump to go to LS fuel pressure (58 psi):
    • 485hp at 80% duty cycle
    • 505hp at 83% duty cycle
    • 545hp at 90% duty cycle
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  • Side note: GM limits max duty cycle to 80% to prevent injector overheating. Practically speaking, you can run beyond that for very short periods of time, but if our OEM follows that limit, you should consider it as well.
  • Permanently gets rid of annoying intermittent misfires at idle due to stock injectors gradually failing, and they WILL fail eventually.
  • Comes with FULL characterization data specifically for LT1 PCMs (voltage offsets and short pulse adders; most tuners just change flow rate and drivability suffers).
  • Requires reprogramming your PCM. If you email me your tune file, I can update the injector data. You can do upload/download easily for the '94-95s yourself with a programming cable and flashHack, or I can do a PCM exchange. For 96s, you can upload/download via TunerCat OBD2 or JET DST but I cannot do '96 PCM exchanges at this time.
  • Injectors come equipped ready to drop in with all necessary adapters. Wiring harness adapters will likely not clear GM corvette fuel rail covers.
  • Only $250 shipped - cheaper than new injectors that don't have characterization data, same price as trying to have your stockers refurbished. Trust me I'm not getting rich off of this. I refused to spend $1000 for Injector Dynamics' injectors so I spent a lot of time digging for an alternative solution. You get to benefit from the hard work.
$250 shipped in continental United States of America.
To get my Paypal info, hover over my username and click "message" or click on my username and then click "start conversation." My feedback is here.
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I have a set of Sherlock’s 36 lb/hr injectors on my wagon.
The injector data provided is 100% accurate; they are a true “plug and play” solution.
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