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World Engine(theta II)

21415 Views 15 Replies 7 Participants Last post by  elecblue06
Ok so I have determined we have the theta II engine... same block used in the hyundai sonata, genesis coupe and i read something about a mitsubishi 4b11t. Now what I was thinking is that since they are the same blocks.. oil port lineups should be the exact same for a suitable amount of heads, thus making them very easibly interchangable... This said, going back to the mitsu engine, going to a junk yard might be our best option in getting parts fast, since the mitsu has forged rods, Mahle pistons and 4 bolt mains.... just an observation seeing that I would like to turbo my kia asap.

What are your thoughts?
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I wouldn't turbo the 2.4 under any conditions. It's a bored out 2.0, and that means less thickness between cylinders, which is not desireable for turbo setup.

Example: Audi A4 used a 3.0 v6, but the S4 turbo was a 2.7. Same engine, Audi just reduced the cylinder size by adding strength between cylinders. They then did the same thing with the newer v6 3.2, reducung it to a 3.0 for the turbo app.

Besides, a lot more goes into making an engine turbo worthy than just forged rods. There are heat dissipation concerns, excess pressure issues, and increased oil flow design and cooling. Not to mention vastly differing compression ratios, intercooler, and an ECM capable of actuating and monitoring a turbo. Then you also have the adddtl stress on the drivetrain, transaxle, and front suspension(significantly more weight).

I would wait until Kia puts a turbo in the koup(it's gonna happen) and then just trade up...save yourself a lot of headache and a ruined car.
yeah, thats why i posted it in the 2.0 discussion... the theta II is the 2.0 correct?
Both the 2.0 and 2.4 are Theta II engines. The world engine is a collaboration between Hyundai, Chrysler, and Mitsubishi. But other than the block being the same, all 3 differ in the design of the head, valves, cams, fuel injection, intake manifold and exhaust header.

Trying to convert a NA engine into a turbo engine is way to involved and tricky to make it worthwhile. Changing turbos in an already turbo'd engine is one thing. This would be a major headache, IMO.
Both the 2.0 and 2.4 are Theta II engines. The world engine is a collaboration between Hyundai, Chrysler, and Mitsubishi. But other than the block being the same, all 3 differ in the design of the head, valves, cams, fuel injection, intake manifold and exhaust header.

Trying to convert a NA engine into a turbo engine is way to involved and tricky to make it worthwhile. Changing turbos in an already turbo'd engine is one thing. This would be a major headache, IMO.
I agree with your statement as a general principal , way too involved for the average bear . That is why it's better left to the pros . The trick is finding and trusting an experienced shop . Almost any low mileage engine can be boosted safely with stock internals at low psi levels . You have to know how to choose the correct turbo or s/c for the application , cool the intake charge and provide some sort of engine management to ensure a safe a/f ratio . The biggest drawback for me is kissing the oem warranty goodbye , that's not a big deal to some .

Both the 2.0L beta and 2.7L delta love boost , they are bored out versions of the 1.8L and 2.5L engines .
I agree with the average bear statement. I'm an aircraft mechanic in the Air Force. Dealing with turbo charged cars is also one of my favorite hobbys. The only thing that is holding me up is engine management. And a possible ecu flash. I would also have to look into fabbing the charge piping and exhaust. My father works on hydraulics and they make pipe benders, so thats not a big issue. The manifold however.... I don't know anyone who can fab a manifold for a t3/t4 setup. I'm also looking at psi levels upwards of 20 in a normal drive. I don't wanna mess with 20 on our stock setup. Thats why I was looking at changing out the internals with the evo. Any thoughts about who can fab a manifold? I looked at the engine bay today, seems like there is plenty of space on the exhaust side to instal a turbo and run charge piping. The intake is at an awkward angle though... might run into some issues there. What about a stroker kit for the na crowd? Running high compression might be a great alternative to boosting. It's most certainly more reliable. Anyone looked at domed pistons and longer rods?

Either route I go, Im wanting to push this engine to the 300bhp range. (had an 01 civic boosted with 280) I think this engine can handle more than the 28 psi I was running on the civic (of course with eagle rods and pistons) Anyone work or have connections with eagle?
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I agree with your statement as a general principal , way too involved for the average bear . That is why it's better left to the pros . The trick is finding and trusting an experienced shop . Almost any low mileage engine can be boosted safely with stock internals at low psi levels . You have to know how to choose the correct turbo or s/c for the application , cool the intake charge and provide some sort of engine management to ensure a safe a/f ratio . The biggest drawback for me is kissing the oem warranty goodbye , that's not a big deal to some .

Both the 2.0L beta and 2.7L delta love boost , they are bored out versions of the 1.8L and 2.5L engines .
Kia tuners? Non-existent, unless you're talking about Asia. Best to have bought a STi or EVO if you wanted that level of performance in a comparably sized car. Of course, at nearly double the price.
I agree with the average bear statement. I'm an aircraft mechanic in the Air Force. Dealing with turbo charged cars is also one of my favorite hobbys. The only thing that is holding me up is engine management. And a possible ecu flash. I would also have to look into fabbing the charge piping and exhaust. My father works on hydraulics and they make pipe benders, so thats not a big issue. The manifold however.... I don't know anyone who can fab a manifold for a t3/t4 setup. I'm also looking at psi levels upwards of 20 in a normal drive. I don't wanna mess with 20 on our stock setup. Thats why I was looking at changing out the internals with the evo. Any thoughts about who can fab a manifold? I looked at the engine bay today, seems like there is plenty of space on the exhaust side to instal a turbo and run charge piping. The intake is at an awkward angle though... might run into some issues there. What about a stroker kit for the na crowd? Running high compression might be a great alternative to boosting. It's most certainly more reliable. Anyone looked at domed pistons and longer rods?

Either route I go, Im wanting to push this engine to the 300bhp range. (had an 01 civic boosted with 280) I think this engine can handle more than the 28 psi I was running on the civic (of course with eagle rods and pistons) Anyone work or have connections with eagle?
I would just wait until a factory turbo Forte model comes out, and then go from there in maxxing it out...which is still a risky undertaking, IMO.

28 psi boost on a Civic? As a daily driver?? How long did it take it blow up?
with forged rods and pistons crank shaft, cam was stage 2 turbo, port and polish head, 1.7 boared out to 1.9 with one of my dad's friend's help, sleved block and of course nitrate valves springs and retainers... i lowered the compression of course and ran high 13's... I was proud.
sorry, to answer your question, it didn't blow until i jumped time getting on the interstate and shot a valve through the head...I was only running 10 psi daily. I never dynoed with 28psi, that was a one time run, and it did great. but once i dropped a valve i put another d17 back in her and sold her for the forte.
Interesting. I was hoping you weren't running 28 psi on a regular basis. Well, it sounds like you had some fun with that engine and car. Good luck with your Forte mods.
Kia tuners? Non-existent, unless you're talking about Asia. Best to have bought a STi or EVO if you wanted that level of performance in a comparably sized car. Of course, at nearly double the price.
plenty of people with boosted kias, rios and spec5's especially
they get their tuning done somewhere
Ok, so I'm just looking for some clarification on the 2.0 Theta II engine in our Fortes. I know that Hyundai developed the block which is the same block used in the Chrysler GEMA engine and Mitsubishi's 4b11t engine. However as mentioned earlier in this thread, each company modified the intakes, pistons, rods, etc. for their own designs.

I know that the 2.0 GEMA engine has continuous variable valve timing (CVVT) on both the intake and exhaust. This is what is listed on the GEMA website (GEMA Engine - 2.0-liter, I-4) and also on the specs for the 2.0 Dodge Caliber. I'm pretty sure that the 2.0 4b11t engine also has dual valve timing, which Mitsubishi calls Mivec. Does our 2.0 Theta engine also have dual CVVT?

Kia.ca lists both the 2.0 and 2.4 engines as having dual CVVT. However, I have a Kia Forte brochure that only lists the 2.4 engine as having dual CVVT. Some google browsing seems to indicate the 2.0 Theta engine may only have CVVT on the intake. Wikipedia mentions this about the Theta but I'm not sure if this is reliable since it doesn't say anything about the 2.4 having dual CVVT. I also found a blog site in Malaysia where they talk about the 2.0 Theta only having CVVT on the intake; (Forte | Yuleehong). Apparently, there is a 165 hp version of the 2.0 Theta that has dual CVVT? Just search for "theta" on that website to that find that specific article. It's a little strange since the Dodge Caliber 2.0 is listed with 156 hp but also lists that it has dual CVVT. Confused yet? Ya, me too...
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My head hurts lol anyone have someinfo on internals aftermarket parts
My head hurts lol anyone have someinfo on internals aftermarket parts
seconded
hope some are in development
especially after the turbos out, we can get some pistons and lower compression and get more power from higher boost
I wouldn't turbo the 2.4 under any conditions. It's a bored out 2.0, and that means less thickness between cylinders, which is not desireable for turbo setup.

Example: Audi A4 used a 3.0 v6, but the S4 turbo was a 2.7. Same engine, Audi just reduced the cylinder size by adding strength between cylinders. They then did the same thing with the newer v6 3.2, reducung it to a 3.0 for the turbo app.

Besides, a lot more goes into making an engine turbo worthy than just forged rods. There are heat dissipation concerns, excess pressure issues, and increased oil flow design and cooling. Not to mention vastly differing compression ratios, intercooler, and an ECM capable of actuating and monitoring a turbo. Then you also have the adddtl stress on the drivetrain, transaxle, and front suspension(significantly more weight).

I would wait until Kia puts a turbo in the koup(it's gonna happen) and then just trade up...save yourself a lot of headache and a ruined car.

comments like this are what hurt my head..:confused::mad:
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