Originally Posted by
martysmartie
No, RS500 blocks are strengthened 205 blocks with small core plugs, (YBD)
Would be from either 4x4 or Escos as none of rest of range had them, the early 4x4s were red tops and had 205 blocks along with many RS500 motorsport revisions.
Martin
Depends what you consider the case to be, the 205/200/and RS500 blocks were different castings, but visually very similar.
RS500 blocks were totally different castings, the smaller core plugs was just chance, designer John Hancock ordered a brand new block produced for these as he considered no reliability in racing above 350 for a 205 block, this block was produced by ford as opposed to cosworth, this was strengthened in several places, including the top deck being thicker than on 205, as the blocks have more wobble than a jelly!!, this was produced on a std production machining line, the lubiraction system was also changed.
tabetha