engine build

[speedncivic]

I am getting ready to build a B18c1 for turbo. I originally planned to bore the block to 84mm and sleeve it, run low compression pistons and rods. However, recently, I was told to bore it out to 2.0L and build it like I were building a B20 for turbo. Does anyone know the advantages and/or disadvantages of both builds?

[superbluecivicsi]

if you plan on sleeving both blocks. advantage vs diaadvantage......................the b20 build is more costly.

[knorwj]

An 84 MM bore would be boring out to a 2.0L B20. I believe right now you are at 81mm.

Thats how they make a B18B into a B20 is by boring it from 81 to 84.

So since you are using a B18c Which has slighly less displacement than a b18B It will still be slightly smaller than a B20 when bored out to 84. However its not a significant difference.

[londa hover]

i plan on sleeving my block, I wanna go with an 84mm bore, if I bored mine to 84mm, I know the oem head gasket will have to be bored out too. But, am I going to have to match port the head? Or can I just leave it? People said all it really does is lower the compresson ratio. Do they make gsr pistons to an 84mm bore or just buy B20 pistons? then would the compression be the same if I bought Supertech 9.6;1 pistons? What all will i really need to go if I bored it out to 84 mm

[TurboGSR96]

i dont think this is possible....i could be wrong....in order to bore a sleeved B18 out to 84mm....you would first either have the machine shop overbore 3mm what they would of previously done or bore the sleeves out once they are installed an extra 3mm, but wouldnt that kinda take away the advantages of an aftermarket sleeve by once again making the walls thinner? please respond if you are on the same page as me on this.

[gmcuajo]

Originally Posted by TurboGSR96

i dont think this is possible....i could be wrong....in order to bore a sleeved B18 out to 84mm....you would first either have the machine shop overbore 3mm what they would of previously done or bore the sleeves out once they are installed an extra 3mm, but wouldnt that kinda take away the advantages of an aftermarket sleeve by once again making the walls thinner? please respond if you are on the same page as me on this.

I don't know too much about that, but if you want sleeve the block and bore to 84mm you have to bore the block to some 86-87mm to make room for the sleeves. This will make the cylinder wall thinner. Search on the web and other forums...