im looking at building a ls vtec engine my question is i wondered if there are a big issue building a b18a vs building a b18a bottom end for it seem to be almost the same block and head will be a b16 cuase i know the b18a dont flow as well

 

Well all flow numbers aside, if you use a B18a head you would just have an LS setup not an LSvtec. Anyway, for the block, other than a slight compression difference which only matters if your using stock Pistons and such the blocks are identical and will not matter whether you use a/b block for the build.

 

ok thank you so much wanted to make sure no sensor holes or ports for stuff not there on the older block for the swap cool cool

 

You can build an LS/Vtec fine with either block. Just get a reputable kit for the Vtec conversion and it will save you a lot of hassle. Also if this is your first hybrid build, two hugely overlooked issues that will cause trouble in the long run:
First make sure the internal Vtec oil passage in the head is blocked. Secondly since these are not a factory Honda produced engine, special attention must be given to properly set the timing and tune your setup. No factory ecu basemap or timing marks will be appropriate for a custom build such as this and you could severely damage the build before you get to enjoy it. Good luck.

 

ok thank u for all ur info