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Oh hay guyze.

So, turns out RB20E's are slow and gutless. I'm considering my various options for conversions. Obviously a full swap to a 25DE is an option, but I'm wondering what might happen if I put the 25DE head on the 20E block? Can that be done, do channels and bolt holes line up? Would I need to change ECU or loom? Straight swap or splicing?

I have a guy who can do the wiring, and we've got everything we need to do that conversion, so I could do it myself over a week or so (planned time, actual time expected to take up to a full month... lol).

If this is a shitty idea, let me know. What other head swaps should I think about? Obviously the 20DE head will fit, and I know that'll be f**k all power increase, but it'd be nice to at least clear 100kw and be able to keep up with a Prius or Tiida... lol. Should I abandon the whole idea and only consider full engine swaps?

Cheers all,
B.

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It's a lot of work then? I was hoping manifolds etc. would be the same, or at least similar enough to make it fit, haha. Just pop it off, pop a new gasket and a better head on, and reattach everything (i.e. a day's work). Out of interest, and so I know, what else would need changing?

But yeah, I can get a 25DE for under a grand, so I see your point. I'll just have to find an engine loom and ECU somewhere, and replace it all, yeah? AFAIK the gearbox and engine mounts wouldn't need changing, but feel free to correct that if I'm wrong there :)

Cheers.

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Given the price that complete engines can be had for, and how much work would be required for the head swap versus an engine swap, I'd go the engine swap

^^ do this. . easiest way to go and no headaches

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The RB20 can't take the head if any other RB without serious custom work to make it fit.

Bore size on the RB is different to a 25, 26, and 30.

Swap hole engine, or swap the whole car.

Thank you, I was after technical reasons it was or wasn't a good idea. Cheers :)

Wont be legal if youre doing this on your ps... sell car buy another or deal with the amazing rarity that is an rb20e.

Lol I don't even remember being on my P's...

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