So I bought an '05 Ralliart a while ago. I've put about 15,000 km's on it, and it's been treating me very well. I use it as a daily driver, and I'd like to keep it around for as long as I can, even if that means doing a rebuild, which brings me to my question: What is a safe overbore for the 4g69 block? It would be neat to have a 2.5L Ralliart, I wonder what the overbore would be and if that would be safe.

I'm not planning on doing this anytime soon, I'd just like to have the info in case I do end up doing it.

 

Only person I know of who has over bored a 4g69 is Mitsuorder. He said he over bored it 0.20

That said there is a 106mm crankshaft that if I did my math right would give the 4g69 2.5l. Its made by Brian Crower.

 

Sounds like a pretty good idea, thanks for the info