Is it possible to purchase them separately to add to a NA 1g block? If so, where?

Tia

The DSM 6 bolt 4g63s all had the "suitcase handle" style main bearing caps whether turbo or not. The 7 bolts have a one-piece girdle style, which is actually a stronger design, it's one of the very few things about a 7 bolt that is. Kiggly actually sells a brace that can be used to tie the caps together on 6 bolts.

Edit: added "DSM"

Thanks for the response! I always thought the SOHC 4g63's (like in a Mighty Max) were missing handles and squirters. Lol guess I was wrong.

If they were non turbo engines, they didn't have the piston oil squirters. However, they do have a pad cast into the block where the squirters would have been and you can drill and tap them to use the 1G style squirters if you wish.

There indeed was individual main cap sirius engines. Think 1980’s era stuff.

I used to use those blocks for strokers, no cap grinding.

I doubt you’ll get a set of paired caps to fit. They not only need to be line bored and honed, but have to fit tight in the main register.