Looks great! The new evo shall rule. Seems like a very good price for all the machine work that has to be done. Good job , and keep up the good work.

 

Could someone explain what the differences and benefits are between an open vs semi closed block are? I have no idea. Thanks.

Later, Ken

 

A semi open deck block has support for the sleeves at the top of the block. In this picture, you can see the supports at the deck that keep the sleeves from moving at all in the block.





An open deck block has no supports at the top for the sleeves. It relies on the sleeve staying in place due to the support from the bottom and the head pushing down on it.





A closed deck block has full support for the sleeves as in this picture.

 

Thanks Ivan for the pic's; they are very informative. As a follow up, would you hazard a guess as to why Mitsu went to the semi closed rather than the closed design? To save weight? If the closed is the strongest, then why not go that route?

Later, Ken

 

AMS, doesn't the 4b11 have iron sleeves stock? I thought I remember reading that somewhere, but perhaps not. If not, then what are the stock sleeves made of? In addition to being made of a stonger material, are these upgraded sleeves thicker as well? Did the support tabs have to be shortened to fit these in, and would that have any compromise in support tab strength? Oh and last question, how much power do you guys think the 4b11 will be good for after this?

 

The 4B11T is not sleeved from the factory. It uses a coating process to harden the wall surfaces. Only time will tell how much cylinder pressure the factory cylinder walls will be able to take before distortion and cracking will occur.

 

Interesting. What I was trying to get at was how much power the 4b11 will handle after the sleeving process that you guys do. Not that I ever plan on going this high, but is 1000 hp a possibility with a built block like this?

 

Best answer ever... and to elaborate a little further.. open deck blocks can have the cylinder liner shake like a cow bell under lots of detonation. this is bad.... clearly a closed deck will prevent this... somewhere in the middle is a semi-closed deck... with theses, the design will dictate the strength... well thought out supports can be just as good as a closed deck with significantly less weight and vastly superior cooling as a result of the additional coolant surrounding the cylinder...

 

Thanks 4G63DSM for info! So the 4B11 may be just as strong as the 4G63 and have more potential durability due to enhanced cooling capacity? I guess AMS would take issue with this since they have sleeved the 4B11. In the end, only time will tell the tale on the limits the 4B11 can take.

Later, Ken

 

The mains are line honed to verify that the machining has 100% not moved the mains. Also in many instances when installing main studs the bores change the slightest bit due to more clamp load. On the Nissan KA motors we run into this all of the time. That is why we have to align hone all of them. As far as the 4b11 goes we are just taking that extra step to make sure that this is the highest quality block available.

 

Eric the block we have lined had cast steel bores. Could you confirm that is the same spec US/UK .

Looking good so far .

 

NOT true,there is the 4b12:
Displacement 2.4 L (2359 cc)
Bore 88 mm
Stroke 97 mm
Compression ratio 10.5:1

Applications
* 2005 Mitsubishi Outlander
* 2007 Mitsubishi Delica
* 2008 Mitsubishi Lancer
* 2008 Citroën C-Crosser
* 2008 Peugeot 4007

 

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evo400, I just got done removing my foot from my own ***. Your right, the 4B11 does have casted in cast iron sleeves. Time will tell how strong they will be.

E7R, there are quite a few differences between the 4b11/4b12 and 4b11t blocks. We have yet to see a 4b12 to determine if it would be a suitable replacement for the 4b11t to handle very high horsepower applications.

 

I think the new 2010 Hyundai Genesis Coupe has 4B11 block too.?