Now doing my first restoration project and have bought an rs with no engine or gearbox.

As im planning to rebuild an engine with forged pistons etc is the NA version of the 1.6 cvh efi any good for this or does it have to be a turbo?

Also which gearbox do i need as i want to run the escort LSD gearbox but they dont all seem to have an LSD, so how do i know which box to get?

 

As an FRST owner I would always say fit a turbo cvh unit to start with anyway , if you then go zetec after then you still have the cvh to go back in to keep it original , you could always go the zetec route straight away as you say you are going to rebuild using forged pistons

On the gearbox front , you can tell an LSD box by looking through the differential , if there is a pin in there it is a std diff , if a hole then it is an LSD .

 

You could use the na cvh if your changing rods and pistons anyway, but you'll need to get an oil return plumbed into the sump for the turbo other than that the blocks are very similar iirc.

 

the crank is different on std NA efi engines such as the xr2i, not by much though, the frst has a throw of 79.5mm xr2i has a throw of 79mm.
blocks are the same apart form the oil return, but as above, you cun put one in the sump, just dont put it too low, you dont want it under the oil level.
where to put it depends if you got T2 or T3, but for what you plan im gussing your after big power meaning a T3 will prob be fitted, if thats the case you have more room for the return.

efi heads are the same inc the cam, i belive the valve springs are rated different for a turbo modle, but there like £4 each or something from fords so no biggy.

choose a cam wisely, i had a kent cam that didnt even make 1200 miles before it was completely fucked, and that was on a freshly rebuilt engine.

if you want massive power, i would say go zetec from the start, the cvh is a good engine and good power can be got with time and money, but lets face it, its had its day compaired to newer engines, i sometimes wish now i stuck to my plan when i restored my rs and went zetec rather than rebuilding the cvh