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Hyundai Genesis Coupe 2.0T Theta engine disassembly, evaluation, and comparison to the Mitsubishi Evo X 4B11T

Today we started a new project. Customer submitted a Hyundai Genesis Coupe Theta 2.0T engine for us to disassemble, assess build quality, and suggest upgraded parts for increased performance and reliability.

Initial observations: the new engine is an all aluminum inline 4. The block is lighter than the old 4G63. Contrary to the old 4G63 found in the Lancer Evolution 7-9, the new engine has the exhaust/turbo on the left side and intake on the right side of the engine. New engine uses bucket-style direct valve activation, compared to the 4G63 using rocker arms. Oil pump is not a separate unit driven by a chain off the crankshaft and located in the oil pan. 4G63 oil pump was timing belt driven and located in the front engine cover. 4B11 does not have balance shafts like its predecessor. Crankshaft is forged and fully counter-weighed. Pistons are cast with friction coated short piston skirts. Connecting rods are “broken” or fracture style. This means the connecting rod is made of powder steel as one piece and precise “broken” during manufacturing in order to separate it. We this being the weak point of the engine. While being adequate for its designed performance duties, the rods become a weak link when increasing engine performance. This can lead to catastrophic engine failures. Our suggestion is replacement of connecting rods in all performance-oriented applications. Main caps are independent on the 4b11 contrary to the 4G63 which has a single cast-iron girdle. Before disassembly we though the engine had the upper oil pan and main caps act as one unit, common practice in racing and even modern engines such as the F20 in the Honda S2000, but this was not the case. The main caps are not tied into the oil pan, nor are they connected together with any type of girdle. This is an area of development we will take on at Pavel’s Racing Engines.

Shortly we will be performing further disassembly of the cylinder head and testing valve springs. We will also provide all component dimensions and weights.

Enjoy the pictures. Most pictures have descriptions. Click to see the details.

15 thoughts on “Hyundai Genesis Coupe 2.0T Theta engine disassembly, evaluation, and comparison to the Mitsubishi Evo X 4B11T

  1. hello I just read your findings on the 2.0t genesis coupe motor. I have a 2013 and was given a set of unorthodox racing lightweight pulleys (crank and alt.) What was your findings more importantly on the crankshaft balance of the 2.0t. Is it ok to run a light weight crank pulley?

  2. Hello Dylan,
    Internal engine balancing is very poor and inconsistent on most Hyundai engines. We weight match all pistons, rods, and performance balance the crankshaft. We have seen crankshaft balancing be off as much as 14 grams. Typically we balance a crankshaft to be under 1 gram. Light weight accessory pulleys will not affect the engine. We recommend against use of aluminum crankshaft pulleys. Stay with an OEM damper pulley or a product from Fluidamper or ATI.

  3. Can you provide me the ARP Main Studs part number you used for these build?

  4. Hello Jesus,
    We have main stud kit available for purchase for $175 shipped in continental USA.
    PRE team

  5. Hello!, hyundai Genesis has exactly the 4G63 engine ? Or other similar to 4G63 engine of Mitsubishi? Thanks !!!!!!!!

  6. Hello,
    Thank you for the message. Hyundai Genesis 2.0 engine is most similar to Mitsubishi EVO10 4B11T engine. It has nothing in common with the old 4G63 engine. If you need more information, don’t hesitate to email us.

  7. Thanks Pavel, so… Theta engine is Korean or Japanese ?

  8. Theta is a Korean made engine. Hyundai, Mitsubishi, and Dodge worked together developing this engine and calling it “World Engine”. General architecture is similar between all of them, but there are major differences and in most case a Mitsubishi engine cannot be easily swapped in a Hyundai or vice versa.

  9. OK. Where can send a mail for recive more information about Hyundai Genesis Engine ?? Thanks..

  10. How many PSI has Genesis turbo “OEM” ? ( Genesis new line, twin scroll turbo 275 HP )
    Someone answers please.

  11. Hello i have a question, i was researching on both motors and found out that the 4b11T is a semi-closed deck block and gen motor is a open deck does this effect performance if so how can i fix that. And is there performance parts from the 4b11T we can use on the gen motor. I just want my motor to be as strong as the 4b11T. Thankd you.

  12. Hello Eddie,
    Thank you for the inquiry. There is no easy way to “fix” the open deck design of the Hyundai Theta engine block. That’s how it was made at the factory. Hyundai block was be machined and fitted a set of Darton ductile iron cylinder sleeves. This converts the block to closed deck configuration and greatly improves cylinder strength over stock. Typical cost of block sleeving is about $2100 and includes cost of Darton sleeves.

    It is unfair comparing 4B11T and Hyundai Theta engine. They started life in the same design room, but the 4B11T has vast improvements over the Hyundai Theta that you cannot easily solve.
    1. 4B11T uses 4 bolts to clamp each main cap to the block. Hyundai Theta engine has only 2. Adding additional bolts is not possible with the block and upper oil pan design.
    2. 4B11T uses bigger rod journals. This increases journal overlap and crankshaft torsional stiffness. This is a plus for a performance engine. Once way to overcome this difference on the Hyundai engine is fitting the 4B11T crankshaft into the Hyundai block or ordering a quality billet crankshaft with oversize rod journals.
    3. 4B11T uses a superior head gasket compared to Hyundai Theta engine. 4B11T head gasket can be fitted on the Hyundai Theta engine, but the drop in compression and increased piston-to-head clearance is not favorable. If choosing this option I suggest custom compression height pistons that will be designed to work with Hyundai block and 4B11T head gasket.

    Ultimately “strong engine” is a relative term. We need to discuss how you will use your car, ie street performance, drag racing, road course racing. Next, engine power goal is set and engine component selection is made based on that goal. Finally, your budget will be dictated by the cost of parts and machine work required to meet your goals.

    If you require more consulting help don’t hesitate to email or call. Thank you.

  13. Hello dear PRE team!
    I have read with high interest your detailed and serious coverage about the Hyundai Genesis coupe 2.0t theta engine.

    I write you from Italy, where the car is EXTREMELY rare and unfortunately unknown to any serious car tuner…

    I have a work in progress soft tuning on my 2012 Genesis Coupe 2.0 turbo: at the moment I have corrected the spark plugs gapping according to the projects specs (1.0-1.1mm), installed an R2C dynamic cold air filter (black hex series) that utilizes the factory air duct, Installed a test pipe (original section), and a Magnaflow 16478 catback exhaust system (3″)..
    I also have already upgraded the clutch/flywhee/clutch slave with the 2013- models as my clutch did start slipping (right now I have 21.000 km on the car).

    My question: I found an ECU tuner who already did few tailor made ECU maps (on the dyno), that claims an expected gain of +30hp and 40nm of torque (as safe

    Together with the performance upgrades, I would ask him to ANTICIPATE for safety reasons the rev limiter of 500rpm, and eliminate the annoying rev-hang issue/feature..

    ACCORDING TO YOUR EXPERIENCE and on the kind of components you have observed inside theengine, do you think that WITHOUT CHANGING PISTONS AND RODS WITH FORGED ONES, the engine would run fine and safe? I am talking of a final result of a car with 230-250hp maximum (I don’t know.. 220/230hp at the rear wheels..?)

    Please…! Help me evaluate correctly the steps to take in a safe direction..!

    Thanking you respectfully and thrustfully, I send you friendly regards from Milan, ITALY!

  14. Hey, just out of curiousity, would it be possible to run a 4b11 block with a theta head in a gen coupe? if head gasket fits I would assume all passages in head are in right spot? I understand custom mounts may be needed but it oil pan in similar location and is tranny bolt pattern the same? I’m not shy for frankenswaps, I currently have a 1jz e46 bmw and I could do the work no problem just wondering about fitment etc, thanks

  15. Hello Ryan,
    The Hyundai Theta head will physically bolt up to the 4B11T block but it is not worth the extra effort to ‘re-engineer the wheel’. The 4B11T block is better than the Theta block, stock for stock, but if you machine the Theta block, install Darton sleeves, ARP hardware, ACL tri-metal rod and main bearings, and forged rods and pistons, it will be very reliable.

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