ok, both of my engines that i was hoping to get one good engine out of are toasted. SO, i'm looking at getting a j-spec TII engine and converting it to NA. I'm sure a number of you are wondering why i want to do this, but i have my reasons. what i want to know is how different from an NA the engine will de-turbo'd engine be? what all else will be required for me to do this? my engines both came out of s4 cars, both NA.

note: i spent 3 hours searching and looking for info on this, but i guess i'm the only one stupid enough to look into it

 

you will have very little power only using 4 ports instead of 6.

 

you cant do it sorry.

 

how about you send me your j-spec TII engine and i will sell you my very N/A engine?

 

Essentially you'd need to build a 4 port n/a motor out of the parts you have, and add some kind of aftermarket lower intake manifold to make the runners and DC work properly for the n/a motor you end up with.

Primary problems with direct short block swap:
- Low compression rotors
- Turbo intake manifold not conducive to n/a flow requirements, ie too short of runners
- Flywheel is larger than n/a and swapping to n/a flywheel is not possible without converting entire rotating assembly to n/a parts due to balance issues

Secondary problems with short block swap:
- Front cover and water pump housing are different
- 4 port block will require carb intake manifold and custom fuel injection or carb conversion

Grinding of the 6 port lower intake manifold to "make it fit" has been done on 4 port motors. But you're still left with the low compression block and need a TII tranny or need to swap the whole n/a rotating assembly.