Can you spot the differences and what do they mean

[kowalatea]

Two blocks, different layouts. Both 75t which block came from which model

[Rusty Nuts]

19 hours ago, kowalatea said:

Two blocks, different layouts. Both 75t which block came from which model

First block is N/A, Turbo oil supply is not drilled and tapped, otherwise no difference. Same foundry, same steel etc

[Dil-Dog]

This is the first time I ever seen a post about this.

I expirenced this before and was super confused because everyone and everywhere claims that all the blocks are the same between s1,s2,s3, Neo turbo and non-turbo.... but this claim is not true and your pics prove it, especially on the deck. (never seen that Before) 

But here are MY personal findings of other differences... When  building my r34. I had a series 3 rb25DET laying around and thought it would be better to throw it in the R34 instead of turbo'ing the DE N/A Neo but when I pulled the engine out I soon realized that the lower 2 holes on the block by the bellhousing ( as seen in your pic) does not exist on the turbo s3 block and What this meant for me was that the 5-speed Small box or rb20det/rb25de gearbox that the car came with will NOT bolt up to the turbo block completely and in fact will be missing four bolts from the trans to the block. these additional four bolt holes on the n/a neo block would hold 2 long brackets that connected to block to the trans as seen below here in the pic.

[SilverECR33]

Other than the fact one has a head gasket and one does not.. Both the NA and Turbo are the same block with different provisions added.

As nissan normally do, there is just additional drill/tapping on the turbo model which is how you identify them. Nissan did the same thing with other models like the RB30 for example. The profile of which is only attributed to the actual build number on block. "75T" Just indicates it is a RB25 block. the 'T' does not mean turbo, this was just coincidence I'm pretty sure. the RB26 N1 Block for example is 24U. But its a 2.6 Litre Twin turbo.

[r32-25t]

Turbo block also has oil squirters 

[kowalatea]

Both blocks have oil squirters 

[kowalatea]

I've also come across this, 

[Rusty Nuts]

On 10/1/2020 at 10:37 PM, kowalatea said:

Two blocks, different layouts. Both 75t which block came from which model

I think that first block is out of a gts4 rb25 Stagea which would account for no gearbox brace holes tapped.