I am about to embark on an mfi to efi conversion on my s2. I have gathered most of the bits required,but my main problem is with the bottom end and the cps.
Is it straight forward to drill a hole in my original block for the cps?
If not, will an xr2i block be ok as a base,obviously with the pistons etc. changed.
I know a frst bottom end is the answer,but i want to make the best use of what i have.

 

Yes, it's straight forward to drill the 30mm hole. Just drill it to the correct position. It's ok to use a XR2i block too with changing the pistons. Then you will need to drill the oil return to the side of the block. The place is there in the block, just needs to be drilled out. I'd say drilling the 30mm hole is far easier if you have a suitable drill bit. A "Christmas tree" like this with a 30m final diameter will be ideal for the job if available.

 

Where will i find the dimensions for the hole,and also the settings for what distance the sensor should be from the flywheel?