bored the ka .020 over now what?

[tc240sx]

kinda new to the whole import scene, just wanted to know what else needs to go along with boring the block on a ka24de.

[liquid_cool]

good word of advice..write all you do to your engine in a journal..since your .020 over..make shure what ever piston and ring combo you go with ..match the overbore...thats all there is to it.

[tc240sx]

ok, do you happen to know anyone that has done it. i'm looking to find out what intake setup would work best with it being bored. i've heard about the cam swaps and it sounds good, i just don't know what would do the job now.

[chr1su12]

Running a larger bore won't make a need for a manifold any different. Neither will the cam make much of a difference..not 0.20 anyway.

When enlarging your bore like that just make sure your cooling system is still running fine and match the rings/piston sizes as said before.

The need to change cams is an efficiency related topic or issue. When running higher compression (not larger bore) the cam choices can be more agressive due to less compression pressure loss due to the higher static compression ratio.

[tc240sx]

yeah ok, i guess i didn't word that correctly. what i meant to ask was if the cam swaps would net the same change in performance with it bored as it would with a stock motor. because reading through here on the cam swaps, i've heard a lot of different stories ranging from excellent to why did i do that? i greatly appreciate your input. thanks

[Ajax]

Like they said above, the change in bore probably won't make much of a difference, unless the pistons you use also change the compression. Most likely, the effects of a cam change would be similar to that of the original bore.

[tc240sx]

thats what i was pretty much thinking. please don't get me wrong i'm pretty good with motors but for some reason messing with this 4 cylinder is so foreign to me.

[tyrodtom]

Have you took the time to estimate how much additional displacement .20 overbore gives you? It works out to about 2 cubic inches. The DE unsupercharged makes about 155 hp, and it has around 146 cubic inches stock, so it makes just a tick over 1 hp per cubic inch. So your maybe 2 inches of additional displacement might give you 2 more hp. You'll get more new horsepower from the improved ringseal on the clean, straight cylinder walls than you will from the added displacement.

[tc240sx]

i'm glad you brought that up. supercharging was also another option i was looking into. if i'm not mistaken the de comes supercharged in a truck right? do you know if the supercharger would fit in the bay of the 240? that would actually be a little more up my alley than a turbo anyway.

[Ajax]

I seem to recall someone did it on here. Had to do a bit of fabrication- I think he used the upper intake runners and replaced the lower plenum with the supercharger. It should fit, but its not exactly bolt-on.

[tc240sx]

yeah, i found it. i would really like to know what the driveability is like with the supercharger. i've always liked the response of a supercharger over turbos anyway.