Need Help Identifying Engine Codes

[Hard-Timess]

I would appreciate help in identifying the following engines.

Block / Date / Casting#
____________________

XX ,,,,, L199, 9799914
(blank) B191, 481988 (complete shortblock)
YS ,,,,, C048, 9790071 (complete #s matching)
YS ,,,,, D308, 9790071 (complete shortblock)

Thanks, Truman ([email protected])

[Ron Landis]

is also the code for my original '69 GTO engine...2bbl., 265 hp.

[Hard-Timess]

The responses do not coincide with the blocks I am looking at. Both the XX L199 engine and the 481988 engine have 4bolt mains. Thus I don't believe them to be low performance 2barrel carb engines. What gives? T

[johnta1]

The XX code 2 bbl engine was also available in Birds.

The XX in my Esprit had the block drilled and tapped for 4 bolt main caps but used 2 bolt caps. (also has 12 bolt rear-end :))

The 72 block is strange, I didn't think they made a 4 bolt drilled 400 block after 1970, except maybe as a SR block.