It's actually a Satin finish - between Flat & Semi-gloss.
In addition to Dave's SEM paint, there is also a Wurth Satin Black that John mentioned, Eastwood's version, & some other satin blacks which are close to original, if he's doing a self-resto paint.
PS - I've also used Geezers' recco'ed Rust-Oleum Satin Black on my 88 Westy, 85 BMW 325e, son's 88 Honda Civic, etc. - which is fine for DD cars & close but not 9 or 10:10 restos - but I don't like the way they get a white oxidation on them within a year or 2 in sunlight, & they also tend to chip more easily on road grit facing items such as the wiper arms.
Most are having to find the formula & have it custom mixed to get exact, if that's what he wants. It was the same satin black as used on the 911/912E black-out grill material too, so a shop doing high quality restos of them would have a line on a contemporary paint which they use (have him/her go to some local PCA Concours & ask where owners have taken their 911/912/914s for restos if they look good).
PPG has a classic section on their website which has most/many of the original mixtures for both trim & main body color paints. There are also some on the Glasurit website (they're a subsidiary of another paint co. now), & both have satin black trim paints in "professional quantities" that are close to the original.
But some codes are not translatable without the original paint makers' materials & tints, so the other option is to have an auto paint supplier "shoot" an unexposed area to get their paint codes to get a match (e.g.: on the engine grill's edge under the lip of the engine lid where it's held in - although that still will have +/-40 years of heat & air oxidation).
The 74-76 914's black bumpers' were the same Satin Black as used on the F & R Valences & Rockers (also on the black-out trim at the sails/rollbar & targa top) with the splatter-shot of VW-Porsche's undercoating material to get that "heavy eggshell" texture (same undercoating as used under the body color paint in the wheel wells & underbody before the body color was shot), then the satin black.
However, the engine grill has no such texture coating, but the parts can & should all be shot as a group to get a good match throughout.
There used to be a factory paint manual the dealers had for "proper factory specification body damage repairs" or some wording like that, which had that & much more info., & would be great to have & reproduce for all - if one could be unearthed. It may
It will depend on how exacting a resto your guys is trying for, & whether he's doing the paint work or his shop.
You might want to post this on the O&H Forum to get some of the other Oldtimer gurus like Pat G. to chime in on their secret formulas & paints, & for other of these types of originality & recreation of same questions.
BTW - most of the targa tops get painted with too much gloss/semi-gloss than was original, &/or they get worn smoother than original ver the years of washing & prepping (same but not as often with rockers, valences, bumpers, engine grills, etc.)
Good on ya for volunteering!
Cheers!
Tom
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