I am new to rotaries so give me a break if this sounds dumb. Is the second gen engine block the same as the third gen block? If it is what were the laragest changes between them besides the turbos and regular bolt on stuff. Any info would help!

 

Different sized ports, different corner seals, different engine mounts.

 

same block though?...meaning i could make a second gen non turbo block into a third gen turbo?

 

No.
The NA engiens are completely different than the turbo engines.
As far as 2nd Gen Turbo engiens go, there are 2 types, the Series4 (87-88) and Series5 (89-91). The S5 is stronger, better ports, and is VERY similar to a 3rd Gen core.

 

Not completly differnt, all housings/plates/rotors/e-shafts can be swaped around to give you the ports/compression ration etc you want. Infact the only differance between the Na engine and the turbo is the porting, T2 has a few extra cooling passages, and a larger oil pump. while the S5 t2 engine is stronger then the s4, the ports are identical. The S6 is slightly stronger then the s5, and has much larger secondary ports and slightly smaller primary ports.

 

I thought NA engines have six ports and turbos four ports?

 

I thought NA engines have six ports and turbos four ports?

 

yes and no,
the S4 engines are basically the same block as the S5 besides the bigger rotors, however everything besides that (oil metering pump excluded) is the same, pretty much, the long block is different tho..and which ports are you talking about? if you mean the T2- exhaust ports then yes, but from what i hear that doesn't really matter to much. the intermedeate housings on a turbo are different, along with some other things, however it's basically the same engine when you pull it apart. (turbo- non turbo).

 

just put a 3rd gen in your car. Take off the sequential setup, sell it, get single turbo