1986-1987 Production Turbo Block 3.8 Liter SG1 Motor
Casting number 25526109



Features of Note:
  • Notice the solid lifter valley with holes drilled for oil return.
  • Notice the knock sensor provision ( hole on left side of picture)
  • Cam end plug (and oil gallery plugs) are in place
Features of Note:
  • Visually, this is a standard prodction block, except for the SG1 casting mark
  • Close examinination may reveal slight casting differences but those could be just variations in the casting process
  • These blocks were the last ones cast and used as replacement and crate motors, as far as we can tell, they were never installed in the TRs from the factory, although they may have been used in the TTAs.



Features of Note:
  • This block has a girdle installed from Loveridge Machine (RJC)
  • The main caps have "ridges" cast into the them, which seem to be indicators of which cap goes in which register
  • Notice how the girdle ties together all the main caps
Features of Note:
  • Notice the casting marks indicate "3.8 GM" on the bellhousing
  • Stock casting number 25526109 shows up at the back of the block
  • No VIN is stamped into the starter pad (since it wasn't installed in a vehicle)
  • SG1 is cast into the front side of the blcok

Submitted by:

Jesse Adkins