L99 6.2L engine: specs, donor vehicles & swap notes
The L99 is a 6.2 L aluminum-block Generation IV engine built 2010–2015, rated 400 hp. It came in 1 vehicle application, including Chevrolet Camaro SS (automatic transmission). Things to know: it has AFM, so an aftermarket cam means a full AFM delete; it has variable valve timing.
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| Spec | Value |
|---|---|
| RPO | L99 |
| Family | Generation IV |
| Years | 2010–2015 |
| Displacement | 6.2 L / 376 ci |
| Horsepower | 400 hp |
| Torque | 410 lb-ft |
| Bore × stroke | 4.065 × 3.622 in |
| Compression | 10.40:1 |
| Block | aluminum |
| AFM/DOD | Yes |
| VIN 8th digit | J |
| Reluctor | 58x |
| Stock cam | Cam PN 12623066; duration 195°/201° @.050 in. int./exh.; valve lift 0.500"/0.492" int./exh.; 115° LSA; 1-bolt gear, 4x; AFM Yes, VVT Yes. |
| Firing order | 1-8-7-2-6-5-4-3 |
| Oil capacity | 8.0 qt |
| Oil filter | 89017524 / PF48 |
| Spark plug | 12621258 / 41-110 |
| Plug gap | 1.0 mm (0.040 in) |
| Head casting | 823 |
- AFM lifter failure (misfire, engine damage). Fix: An AFM disabler is a device you plug into the vehicle's OBD-II port to deactivate the system at the ECM level.
- AFM lifter tick. Fix: Check the oil condition and level frequently to avoid lifter trouble.
- AFM-related oil/carbon issues. Fix: Check oil condition and level frequently.
Aluminum, AFM, VVT, E85-capable
The L99 specs above are not yet confirmed against GM documents; GM ratings varied by year and vehicle.
How the L99 differs from the other 6.2 L Gen IV engines
The L99 is one of the seven 6.2 L Gen IV engines we list: L92, L94, L99, L9H, LS3, LS9, LSA. From our engine table:
- AFM (cylinder deactivation): yes. Same as the L94; the L92, L9H, LS3, LS9, LSA don't.
- Compression 10.40:1, within the group's 9.1–10.7:1 spread.
- Up to 400 hp from the factory (7th of the seven 6.2 L Gen IV engines we list; the group tops out at 638 hp).
- Variable valve timing. Also on the L92, L94, L9H.
- Built E85-capable (flex fuel) from the factory. Swapping an L99 onto E85 still means wiring the flex sensor and setting up the tune for it.
- Built 2010–2015.
Swapping the L99: what to plan for
- Computer: the L99 has a 58x crank. An E38 or E67 matches it; a 0411/P59 also needs a 58x-to-24x converter box and its own sensor and knock-sensor wiring. Throttle and wiring have to suit the computer too. More: how to wire your LS (the full checklist for your engine and computer).
- AFM: a stock-cam L99 can have AFM turned off in the tune; an aftermarket cam means a full AFM delete (non-AFM lifters and trays, a non-AFM valley cover, the tune). More: LS cam swap guide.
- VVT: on a VVT L99 the cam phaser and VVT timing cover change what bolts on: only some water pumps clear a VVT timing cover, and a non-VVT cam needs a VVT delete and a tune. More: accessory drives.
- From a 2010–2015 Camaro: truck accessory spacing, and the 2010–2015 Camaro pan only fits its original car (avoid it for a swap). More: oil pans.
Refresh parts for the L99
From our Gen IV refresh list, the parts that are specific to the L99. Seals, gaskets and the upgrades worth doing on any Gen IV with the engine out are in the full refresh list, next to every torque spec.
| Part | GM part # | Why for this engine |
|---|---|---|
| LSXceleration Gen IV LS knock sensor 28-23730 | 28-23730 | The L99 has its knock sensors on the side of the block. |
| GM Gen IV camshaft position sensor 12591720 (58x engines) | 12591720 | 58x L99: the cam sensor lives in the front cover. |
| Chevrolet Performance 58x crankshaft position sensor 12703627 | 12703627 | 58x L99: the crank sensor is behind the starter. |
| GM oil pressure screen/filter 12585328 (AFM valley cover) | 12585328 | On 2007-and-later AFM V8s: Clogged screen starves the sender and causes false low-pressure codes on AFM engines. |
| Genuine GM 12610141 valley cover gasket (LS2/LS3, no AFM/DOD) | 12610141 | Needed if you delete AFM on the L99 with a non-AFM valley cover. |
From real tunes: 6.2 L on a Gen IV computer
What these settings look like in the 462 naturally aspirated pump-gas tunes for 6.2 L engines on Gen IV computers (E38, E67 and the 24x E40) in our tune library (as of 2026-10-15). Every RPO of this size is pooled, not only the L99, and so are all cams, heads and builds: that is why the ranges are wide. Use them to spot a value that is far outside what works, not as your numbers.
| Setting | Range | Median | Tunes |
|---|---|---|---|
| Hot idle target | 550 rpm to 900 rpm | 700 rpm | 462 (middle 80%) |
| Warm idle airflow, in gear | 6.5 g/s to 13.2 g/s | 7.9 g/s | 462 (middle 80%) |
| Idle spark (around 800 rpm) | 13° to 21° | 15° | 462 (middle 80%) |
| Power enrichment (PE) lambda | 0.76 to 0.86 | 0.79 | 449 (middle 80%) |
| WOT spark at 5,000 rpm, about 0.9 g/cyl | 11.0° to 27.5° | 20.5° | 462 (middle 80%) |
For starting values matched to your L99's cam, injectors and fuel, use the turn-on tune builder. Always finish on a dyno, and read our safe tuning limits before any wide-open pass.
Donor vehicles with the L99
Where to find an L99 at the junkyard: 1 vehicle application below. Confirm it from the RPO sticker in the glovebox or the 8th VIN digit (for the L99: J).
| Vehicle | Years |
|---|---|
| Chevrolet Camaro SS (automatic transmission) | 2010–2015 |
Buying a used L99
A used L99 has no single part number, so this page does not link a search. Confirm the engine from the RPO sticker or the 8th VIN digit (for the L99: J) before you buy.