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Fuel Injector Reference / Chevrolet and GM

Chevy and GM LS Fuel Injector Reference

Every common Gen III and Gen IV injector in one table: LS1 through LS9, Vortec truck engines, GM and Bosch part numbers, flow at 58 psi, and the three details that decide interchangeability: body height, o-ring size, and EV1 versus Multec versus EV6 connectors. Compiled by the injector cleaning department at Boost Lab, Inc.

LS1 / LS2 / LS3 / LS7 / LS9VORTEC TRUCK 4.8 / 5.3 / 6.0GM + BOSCH PART NUMBERSFLOW AT 58 PSIASNU BENCH VERIFIED
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The three things that decide an LS injector swap

LS injectors interchange on three axes: flow, height, and connector. Passenger car LS1 injectors are tall EV1 connector units; early Vortec truck injectors are much shorter with Multec connectors; Gen IV LS3 style injectors are shorter still with USCAR EV6 connectors and a larger lower o-ring. Get the height wrong and the rail does not seat, get the connector wrong and you need adapters, get the o-ring wrong and you get a high pressure fuel leak.

GM rates these injectors at 58 psi, not the 43.5 psi standard most aftermarket injectors are quoted at. That difference is why the same Bosch injector can carry two different published numbers depending on who is quoting it. All figures in this table are at 58 psi so they compare directly.

The popular budget upgrades come straight from this table: LS3 and LS7 share the 42 lb injector, LS9 and LSA share the 52 lb unit, and the Gen IV flex fuel truck injectors are drop-in high flow options for the 4.8, 5.3, and 6.0 rails. All are high impedance, so any factory or aftermarket LS ECU drives them natively.

Showing all 14 applications
EngineYears / ApplicationFlow @ 58 psiConnectorImpedanceOEM / Ref PN
LS11997-98 Corvette, F-body26.2 lb/hrEV1 tall bodyHIGH IMP12554271, 12533952
LS11999-200027.3 lb/hrEV1 tall bodyHIGH IMP12555894 / Bosch 0280155890
LS1 / LS62001-0430 lb/hrEV1 tall bodyHIGH IMP12561462 / Bosch 0280155931
LS22005-06 GTO, Corvette34 lb/hrEV6 USCARHIGH IMP12569113 / Bosch 0280158049
LS3 / LS7 / L99 / L762008+ Corvette, Camaro SS42 lb/hrEV6 USCARHIGH IMP12576341 / Bosch 0280158051
LS9 / LSAZR1, CTS-V, ZL152 lb/hrEV6 USCARHIGH IMP12598646 / Bosch 0280158187
Vortec Gen III and Gen IV truck engines below. Early truck injectors are short body Multec; 2007 and later move to EV6 USCAR.
LR4 / LM7 4.8, 5.3199921.8 lb/hrMultec short bodyHIGH IMP25317669, 25320287
LQ4 6.0 / 4.8, 5.31999-200024.8 lb/hrMultec short bodyHIGH IMP25317670, 25320288, 25323974
4.8, 5.3, 6.0 trucks2001-0725.2 lb/hrMultec short bodyHIGH IMP25317628
L59 5.3 flex fuel2002-04, return style33 lb/hr @ 50 psiMultec, taller bodyHIGH IMP12580426
L59 5.3 flex fuel2005-07, returnless36.6 lb/hrMultec, taller bodyHIGH IMP25326903
LY6 / LY5 / LY22007-09 trucks30 lb/hrEV6 USCARHIGH IMP12580681 / Delco 217-1621
LMG / LMF / L202010-17 4.8, 5.336 lb/hrEV6 USCARHIGH IMP12613411
L96 / flex fuel trucks2010+, drop-in high flow44-50 lb/hrEV6 USCARHIGH IMP12613412, 12609749
GM rates flow at 58 psi (4 bar)HIGH IMP = saturated driver (12 to 16 ohm)LOW IMP = peak and hold (2 to 5 ohm)
O-ring detail: Gen IV LS3 style injectors use a lower o-ring roughly 0.025 to 0.030 inch larger in diameter than earlier LS injectors. Fitting an earlier injector into an LS2 or LS3 intake needs the larger 0.570 inch o-rings, and mixing rails, spacers, and injector heights is how high pressure leaks happen. When we service a set we return it with fresh correct o-rings installed.

What we see on the bench

Tired truck injectors

High mileage 5.3 Vortec sets with one or two units flowing well below the others, showing up as lean codes and a shaky idle. Cleaning and matching usually beats gambling on used replacements.

Junkyard LS3 sets

42 lb takeout sets are the default swap injector. We verify the actual flow of each unit and match the set of eight so the tune starts from known numbers.

TPI and LT1 classics

Pre-LS Bosch EV1 injectors from TPI and LT1 cars respond extremely well to ultrasonic cleaning, and originals are getting scarce. Covered in prose here, verified on the bench individually.

Frequently Asked Questions

Are LS3 and LS7 injectors the same?

Yes. Both use GM part number 12576341, a 42 lb/hr high impedance EV6 injector, which also appears on L99 and L76 engines. LS9 and LSA likewise share the 52 lb/hr 12598646 injector.

Why do LS injector flow numbers differ between sources?

GM rates its injectors at 58 psi while most of the aftermarket quotes 43.5 psi. The same physical injector flows noticeably more at 58 psi, so always note the test pressure before comparing numbers or entering data into a tune.

Will LS truck injectors fit my LS1 intake?

Not directly. Truck injectors are much shorter than tall LS1 injectors even though the o-ring sizes match, so the rail will not clamp them at the correct height without hardware changes. Match injector height to the intake and rail combination first, then flow and connector.

What injector data does my tuner need?

At minimum the true static flow at a known pressure and consistent behavior across all eight injectors. Our ASNU bench report documents each injector's flow before and after service, which gives your tuner real numbers instead of catalog assumptions.

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