I used a Sperry/Univac 1100 at university, so this was an interesting read:

http://people.cs.und.edu/~rmarsh/CLASS/CS451/ … S/os-unisys.pdf

Sperry Rand was also fortunate to have a good FORTRAN compiler and some program conversion tools. The FORTRAN V compiler for the 1108, written by Computer Sciences Corporation, produced very efficient programs. At a meeting of Burroughs engineers discussing their competitors, Robert Barton referred to it as “a polished masterpiece” and another participant said: “You sit there and watch the code that thing cranks out and just try to imagine assembly code that would be written that well.” Lockheed developed a “decompiler” which translated IBM 7094 machine language programs into NELIAC. One of these decompiled programs comprised 500,000 instructions. There already was a NELIAC compiler for the 1107 (and later for the 1108). At Air Force Global Weather Central these doubly translated programs ran much faster on the 1108 than IBM's 7094 emulation did on the 360. Sperry Rand had a program that translated 7094 assembler programs to 1108 assembler, and Boeing developed another program that converted IBM 7080 Autocoder programs to the 1107 and 1108. The 1108 did well in competitions: a single processor 1108 outperformed an IBM 360/65 and a GE 635 on benchmarks done for the University Computing Company in 1968.

(...) it was clear that there needed to be a less expensive entry into the 1100 world. Sperry Rand announced the 1106 in May 1969 to meet this need. The first few machines shipped as 1106s were really 1108s with a jumper wire added to the back panel to introduce an additional clock cycle into every instruction. Astute customers soon learned which wire they had to clip to speed up their 1106s.