Forged pistons

[Allan]

How much slap should i be seeing with forged pistons ?

This seems quite a lot...
http://www.youtube.com/user/Mrnigglesworth

Basicly rebuilding this block and the pistons will be coming out, but want opinions from poeple who have fitted forged if this is too much movement....

And if it is what to do to fix it.

Bores on the block look fine and i measured it with some cheap vernias which read 82.8mm but they are very cheap ones so could be out..

anyways its wossner low comp pistons in a f7r 700 block

[Coops]

mine are quiet as a mouse mate

[Justin..]

as above, mine just sounds like a normal cast engine

[Allan]

well not run it yet, just trying to figure out if the bores are oval really, as there is no movement the other way

[MAXIBOY]

have you had the block honed..

[Laine_16v]

After i had my block rebuilt, i.e. fresh honed, new rings e.t.c

You could move the pistons very very slightly in the bore, but your video it does look quite excessive. I dont get an piston slap from cold either.

[sideways danny]

pistons aren't round, that's why they move more in one direction than the other. That are also not "square" having tapered skirts, meaning there is more clearance at the top than the bottom, ALWAYS

[Glekke]

pistons aren't round, that's why they move more in one direction than the other. That are also not "square" having tapered skirts, meaning there is more clearance at the top than the bottom, ALWAYS

true... but this just looks to much...

[Allan]

Well looks like the 1 could be an issue, the others dont move so much, got new rods to go in so might replace the rings too and rebuild and see how it goes.

[Crossers]

Mine seemed a little loose when i was building my tubby, I could wobble them, but there was no slap at all when running even from cold.

Paul