Was wondering how much one can bore out on a 2.4l ralliart engine without thinning out the cylinder walls. considering that instead of doing a turbo setup. also will i need bigger injectors for the increased displacement or will the stock ones do after a tune?

 

take your block to a reputable automotive machinist and they should be able to tell you what you can get away with or what they are willing to do for you.

and turbo is cheaper...

 

There's really not lot of meat left to bore, I mean the 4g69 (87mm)is basically a bored out 4g63(85mm)You should be able to get .5mm safely but it will hardly be noticeable, but your wallet will feel it. You could get more just by upgrading the cr from 9.5:1 to say 10.5:1 or 13:1 if your feeling lucky. But like crans said going turbo will be cheaper. And you'll get more hp. Upgrading the block should be done after you've pushed the limits of the oem internals, which is around the 300hp range. Do some searching this kinda thing has been discussed before.

 

I have bored 4 cyl engines before and always had problems. I ended up having my cylinder walls go egg shaped resulting in a ton of blow by and massive plumes of smoke coming out of my exhaust every time I punched it.

I think in this day and age that forced induction has proven to be the cheapest and most reliable way to make meaningful power.

Many RA owners have proven the 4G69 can safely handle low boost and be very reliable doing so.