The Ford Barn

TDS · 10-19-2015, 01:45 PM

Hi

Looking for new pistons and pistonrings.
I havnt pulled the pistons yet but Im trying to locate the right parts.
I'm from Denmark and we use metric dimensions.

I messure the cylinder bore to just around 77,9 mm, thats 3,066929", with my vernier.
Not 100% I know but I havnt found a mikrometer gauge yet.

Which US piston size matches that?

Thanks..

bobH · 10-19-2015, 02:47 PM

Something to file away 'in memory'.... 25.4 mm/in
So, 77.9 / 25.4 = 3.067. Standard bore for 3-1/16 = 3.062 (5).
You probably have a standard bore, with .005 wear.
So, probably standard 3-1/6 in pistons.
Oversized pistons are usually marked (stamped) on top with the oversize, like .020, .030, .060, etc. Sometimes standard pistons are marked 'std'.

KiWinUS · 10-19-2015, 03:43 PM

You have many choices of where to buy , my suggestion would be to buy your pistons from a supplier that can supply any other parts you need . H7H Flatheads would be just one good source .
Cheers
Tony

OHV DeLuxe · 10-23-2015, 12:04 PM

Sponsored Links (Register now to hide all advertisements)

TDS, i have a set of nos pistons for 3 1/16 engines right here in Norway Think they are .030.

10-19-2015, 01:45 PM	#1
TDS Member Join Date: Sep 2015 Location: Denmark, Aarhus Posts: 49	Piston size Hi Looking for new pistons and pistonrings. I havnt pulled the pistons yet but Im trying to locate the right parts. I'm from Denmark and we use metric dimensions. I messure the cylinder bore to just around 77,9 mm, thats 3,066929", with my vernier. Not 100% I know but I havnt found a mikrometer gauge yet. Which US piston size matches that? Thanks..

10-19-2015, 02:47 PM	#2
bobH Senior Member Join Date: May 2010 Location: so cal, placerville, vegas Posts: 1,394	Re: Piston size Something to file away 'in memory'.... 25.4 mm/in So, 77.9 / 25.4 = 3.067. Standard bore for 3-1/16 = 3.062 (5). You probably have a standard bore, with .005 wear. So, probably standard 3-1/6 in pistons. Oversized pistons are usually marked (stamped) on top with the oversize, like .020, .030, .060, etc. Sometimes standard pistons are marked 'std'.

10-19-2015, 03:43 PM	#3
KiWinUS Senior Member Join Date: May 2010 Location: Charlotte NC KiWi-L100 available here Posts: 2,963	Re: Piston size You have many choices of where to buy , my suggestion would be to buy your pistons from a supplier that can supply any other parts you need . H7H Flatheads would be just one good source . Cheers Tony

10-23-2015, 12:04 PM	#4
OHV DeLuxe Senior Member Join Date: May 2010 Location: Norway Posts: 298	Re: Piston size Sponsored Links (Register now to hide all advertisements) TDS, i have a set of nos pistons for 3 1/16 engines right here in Norway Think they are .030.