spark plugs for renault 750

[octavia]

What are the best spark plugs to use in a 4cv /750? Can i use NGK BP5ES will they be ok.Engine run up for 40 minutes no blue smoke and no detectable blow by at oil filer cap.Generator charging ok.Where can i get an Australian assembled 750 wiring diagram? Car made in 1961.According to data i have.
RP.

 

[JohnW]

What are the best spark plugs to use in a 4cv /750? Can i use NGK BP5ES will they be ok.Engine run up for 40 minutes no blue smoke and no detectable blow by at oil filer cap.Generator charging ok.Where can i get an Australian assembled 750 wiring diagram? Car made in 1961.According to data i have.
RP.

Not a high performance engine so I reckon it doesn't matter much.

Used to be Champion L10 before projected core plugs appeared.

NGK BP6HS is about right - the "5" is a hotter plug I think and probably over the top. Good plugs though.
Bosch W6AC too.

I reckon all that really matters is that they aren't too hot (5 max on NGK (smaller is hotter), 7 on Bosch (larger is hotter)) and the piston doesn't connect. Don't go colder of course.

This stuff is all over the web. Hard to find 4CV on charts, but Dauphine, early R4 are there, as are the conversion charts.

For the wiring, nothing is brilliant but there's not much wiring. There are often Renault 750 workshop manuals on ebay, the "Scientific Publications" one with a red and black front cover. There was one the other day.