andy130

iTrader: (2)

as above set a set for sale at a good price but dont want to fit them an slap none stopare they a good piston aswel?

hitchwest

iTrader: (2)

my mates slapped in his saff tbh would go there

GavStyli

i have them in mine, and they dont slap!

liam-rst

iTrader: (1)

from wot ive read most forged pistons slap when cold, cant say i have any first hand experience tho

Chip

iTrader: (3)

The slap noise is caused by the piston to bore clearance allowing the piston to move, if you install them with the correct clearance as per the manufacturers instruction there should be very little slap.

ANY forged piston does require a bigger than standard gap though, its not just one make, so its inevitable that there will be a little noise on very cold days compared to a new standard piston.

The normal problem is people who take a 80,000 mile old block, then hone it, then fit a set of pistons, and its all sloppy as a result.
Rebore to an oversize with the correct clearance is the only way to get it right.

Karlos G

iTrader: (4)

As above, I run them and from cold there is a little slap for the first few minutes, perfectly normal.

12_Second_rst

iTrader: (1)

i run them in a zetec and get no slap

s1cab

iTrader: (1)

mine are fine

darrenb16two

Jano built my steel bottom end with wossner pistons and i have no slap at all

DazC

iTrader: (1)

My own engine runs Cosworth forged pistons and from cold they are a little noisy. Once warm they are quiet.

I have also built an engine with Wossner forged pistons an they were slightly quieter than my Cosworth pistons and went quiet once warm.

Both engines were bored to the recommended tolerances and I seem to remember the Wossners being around 4 thousandths of an inch clearance gap.