Trivial differences in S13 Redtop and Blacktop...

[COstyle]

Ok ok its been discussed a billion times before. S13 Redtop and blacktops are virtually the same in every aspect minus blacktops are from newer cars. But I know there are some very small trivial differences and for the books I'd be interested in knowing them. Say someone put swapped a black valve cover on a redtop s13, would you know it was a redtop? From searching I've only come up with 1 difference. In US s13s blacktops require the SR a/c compressor where redtops can be rigged with a KA compressor? And I also read that on late model blacktops the heads were produced from a different mold and have notable markings? Can anyone add to that...?

[cowbomb]

id like to know some more too............ ive heard the differences with the s14 and the s13 but the only differences in those are the turbo size