What is the difference between a STI and STI RA engine? I want to swap my my97 wrx engine to an sti ver3 or 4, but still not sure for which engine I should go for. I was also told that the wiring harness is the same, is this true? What ever engine I'll get I'll be keeping stock.

And is it a good idea to get an STI engine and a STI RA ecu?

 

I think the STI RA engine is the same as the STI engine (there may be minor differences but nothing to worry about). The map in the ECU may be slightly different but I doubt it. The RA magic comes from the lighter weight and shorter gearing

 

This is what reply I got from someone else:
STI and STI RA engines is the same, but the RA engine has some little changes, eg the valve lifters which enables it to rev higher;RA engine has 7,800 rpm red line in comparison with the Standard STI that has only 7,200;The RA has slightly stronger internals.The ECU is programed on280 bhp, in comparison with tthe Standard STI-which is 260.The RA ECU has 3 plugs, and the Standard STI has 4.

What worries me is why the ECUs have diferent pinouts?

 

If your talking about the V3, then both push out the same power, 280ps.
The engines should also be the same, no differences with the internals etc, the wrx engine on the other hand will be different.
The biggest difference with the Type RA's over the standard STi's are a shorter ratio'd gearbox and the 30kg less.

Tony

 

Thats what I thought, but then the engine number of the STI is EJ20K DW6PR while the RA is EJ20K DW6PJ ......so there has to be some difference.

 

I also just noticed that the STI and WRX have both the same gearbox (TY752VBCAA), but the RA has a different one (TY752VB5CA). Would my WRX gearbox still work with an STI RA engine?

 

sti ra should have a 5th injector in the intake manifold.. manifold is not painted red either .. as in my 95 sti ra version 2.. go for any sti version 3 engine...

 

97 sti ra does not have the fifth injector!

 

Yeah I think I would go for a STI ver3, should be the cheapest of the whole sti lot. Has anyone got a photo of the ECU, so i can compare the wiring to that of my WRX?

 

If it's the same year, it'll be the same connector.

 

Thats good news, what about the inlet, would the WRX fit directly to the STI block? I heard that its the same of the STI but painted red.
And back to the ECU, it might have the same connector, but would have the same wiring positions? ......photos appreciated here from sti ver 3 /4 owners