Hyundai Genesis Forum banner
11K views 23 replies 11 participants last post by  8cd03gro 
#1 ·
Well then at least drop the oil pan to see if it has the 4 bolt mains. That's one thing I'm very curious about, but haven't been able to find any answers on.

Kevin I just looked at the service manual, it looks like the Theta engine only has 2 bolt mains. I'm not sure what kind of difference 2bolt vs 4 bolt makes. Perhaps one of the experts can elaborate.

edit: a snippet from the service manual
---------------------




 
See less See more
1
#3 · (Edited)
A 4 bolt main engine has a stronger crankshaft that doesn't flex as much, the block is also stronger & will not flex as much either. This engine will have less vibration than the 2 bolt main & is better for running at higher RPMs. So, the EVO & SRT4 4 bolts are better than the GenCoupe 2 bolt, but in today's engines, the difference between the 2 is not as big a difference as in the "old school" engines. Once again, we'll just have to see what these things are capable of.



 
#4 · (Edited)
So by looking at this diagram of the main caps and bolts for the 3.8, I guess it would be safe to say that the mains on the V6 are 6 bolt? This isn't really my area of expertise, so I may be wrong...



EDIT: Crap, sorry I guess it's on a transparent background, but I think you get the point...
 
#10 ·
sabbasaun HELP!

sabbasaun, I want to move all the info not dealing with Jrod's purchase of his new car to seperate thread in the engine/turbo section & title it 4 bolt vs 2 bolt main or something of the sort starting with the question from Kevin DSM about which this is, but I don't know how. Can you help me?



 
#14 ·
Open deck and 2-bolt mains are confirmed by redline's disassembly of the 2.0 theta motor. Personally, from the experience that I have had with various motors (a couple of 2.2 mazdas, 4g63 mitsu, 2.0/2.2 subie, and 1.5/1.6 honda motors) it all comes down to tuning. I have made solid hp numbers with no block integrity issues on open deck motors (245whp on a D15B honda) with stock components. I feel really confident in the design of the 2.0t theta and think that all of us will be pleasantly suprised with its potential.
 
#18 ·
it's cool, I'm one of the ones that promotes reawakening the dead threads when someone has new insigt or something to add. I would much rather rivive an old thread than starting a new one on the seme topic.
 
#20 ·
You're right to some degree. In all reality, balancing of the bottom end really is what matters here. Harmonic combustion is something that requires very delicate and precise tuning. With good tuning and a proper engine setup there shouldn't be much concern for the motor being 2 bolt mains versus 4. If anything, this should make people value a good tune/tuner just as much as the quality of parts they put in their car.
 
#21 ·
+1

Don't worry so much at this point on the details like, 2 vs 4 bolt, or forged this or that.. the serious experienced guys will tell us where we will be able to take the 2.0t engine in its stock form and do it safely and reliably. Remember this car has only been in the hands of the US guys for a 2-3 months but we've already seen great results :)



 
#23 ·
Just re-read this thread.

FYI the Caliber SRT4 motor is a 2 bolt main fully open deck motor.

We have made 570whp through this motor and will be building the motor to push it farther shortly.
Well that confirms to me that the 2 vs 4 debate isn't really a debate .... at least not at those puny power levels lol :)



 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top