Same displacement, different families
The G4KD belongs to the Theta II family: 1,998 cc, square at 86 × 86 mm, an aluminium block, a chain-driven 16-valve head with dual CVVT and a two-stage variable intake, and multi-point injection. It arrived in 2007 and was fitted through the mid-2010s.
The G4NA belongs to the newer Nu family, introduced in 2010–2011: 1,999 cc from a smaller 81 mm bore and a longer 97 mm stroke, aluminium block and head, dual CVVT and multi-point injection. It is not the Nu 2.0 GDI (G4NC) nor the CVVL version (G4ND), which are separate engine models.
| G4NA | G4KD | |
|---|---|---|
| Family | Nu 2.0 MPI | Theta II 2.0 MPI |
| Displacement, bore × stroke | 1,999 cc, 81 × 97 mm | 1,998 cc, 86 × 86 mm |
| Valvetrain | DOHC 16-valve, dual CVVT | DOHC 16-valve, dual CVVT, two-stage VIS |
| Typical output | About 152–166 PS depending on version | About 165 PS |
| Typical vehicles | Tucson ix35 LM (2013–2015), Tucson TL, Elantra UD/AD, i40, Sonata YF (2014), Sportage (2014–2021), Forte/Cerato YD, Soul, Optima, Carens RP | Sonata (2007–2014), Tucson ix35 LM (2009–2015), Sportage SL (2010–2013), Forte/Cerato TD, Optima (2008–2012) |
| Published price (per unit, FOB, full container) | US$ 740 | US$ 500 |
| Matching gearbox (mixed configurations only) | US$ 150 | US$ 120 |
Why buyers mix them up
Both are four-cylinder 2.0 petrol engines with the same "G4" prefix, and the Tucson ix35 (LM) was sold with either engine in 2013–2015. The Sportage switched from the G4KD in the SL generation to the G4NA from about 2014, and the Sonata YF used the G4KD for most of its run and the G4NA in 2014. A counter that orders by vehicle name and engine size will receive the wrong model a good part of the time.
They are not interchangeable: different bore and stroke mean different pistons, rods, crankshaft and head, and the engine control unit is calibrated for one or the other. The family page Hyundai-Kia Theta, Nu and G4 lists every model we publish.
How to tell them apart before you order
Read the engine model from the engine itself: Hyundai and Kia stamp the engine number on the engine block, and the engine model — G4NA or G4KD — is part of the markings on the block. The third letter is the family, N for Nu and K for Theta. When you ask your customers for photos, ask for that stamping as well as the vehicle identification plate and the model year.
On our side, the photos in your order file show the engine code or identification plate where it is visible on each engine. Our check is the same for every engine: cleaning, handling, a manual crankshaft rotation with a tool to confirm the mechanism turns, and photos from every side, delivered to you as an order file — Engine 1, Engine 2 and so on. It is not a compression, leak-down, bench or running test, so it does not prove how an engine will run once installed. You don't need to travel to buy, but you or your representative are welcome to visit for a Guangzhou Inspection Day and review your prepared lot in person, with a USD 1,000 visit deposit credited to your order. Our guide how to identify an engine model covers the other brands.
Sources
- Hyundai Nu engine — Wikipedia (specifications, years and applications)
- Hyundai Theta engine — Wikipedia (specifications, years and applications)
- ENGICOR prices and terms: our own published list, recorded monthly in the used engine price index.
Price a container yourself
Build the mix you want in the online quoter — 90 engines in a 20-ft or 130 in a 40-ft, or 45 + 45 / 65 + 65 with gearboxes — and the FOB total reaches your inbox the same minute, at our published per-unit prices, every engine Grade A. Prefer to ask? Tell us the destination country and the models you need and we reply within one business day, usually within hours.
Frequently asked
What is the difference between the G4NA and the G4KD?
The G4NA is the Nu 2.0 MPI (1,999 cc, 81 × 97 mm) and the G4KD the Theta II 2.0 MPI (1,998 cc, 86 × 86 mm): same displacement and both multi-point injected with dual CVVT, but different families with different internal parts.
Does the Hyundai Tucson ix35 have a G4NA or a G4KD?
The Tucson ix35 (LM) used the G4KD from 2009 and was also sold with the G4NA in 2013–2015, while the later Tucson TL uses the G4NA — read the engine model stamped on the block to be sure.
Which is cheaper, the G4NA or the G4KD?
The G4KD, at a published US$ 500 per unit against US$ 740 for the G4NA, both FOB inside a full container of 90 (20-ft) or 130 (40-ft) engines.