Engine rattle/piston slap

[fremyjay]

How many people have this on their forged engine, going to look at an engine next weekend and it has rattle at top end when cold but goes when warm, heard this is normal for weisco pistons

[Jim*]

Yeah I got forged engine mate apparently it's because when cold the pistons have a bigger clearance for expansion when they get hot. Don't quote me on that though I'm sure somebody will correct me if im wrong

[fremyjay]

Yeah exactly what I thought, just asking for peice of mind really bud

[The Toffinator]

Could be piston slap, or valve clearances mate. Either of them arent a major problem but worth checking top end tolerances. Some forged builds do tap from cold though as they are usually bigger clearances

[Jamie1st]

Mine slaps from cold. Wiseco pistons and about 5k miles on the engine with no trouble. Gets hard track use.

[micky boy]

I've never hear a forged engine not slap from cold

[fremyjay]

Do they tend to slap abit when warm too???

[Phil]

My engine slaps it tits off all the time.

BUT been running fine for 4odd yrs so i wont be getting myself overly worried.

and no i didnt build it myself, our home built baby was sweet as a nut, this slappy jalopy was a massive companys build attempt.

but again i would hasten to addi cant complain too much as A) i didnt pay to have it built and its still runs grand.

Phil

[fremyjay]

excellent exactly what i was wanting to hear

[Taggy]

Yeah its totally normal, depends on how its built really, different piston manufactures have different recommendations on piston skirt clearance. I would say its fine.

[dazzi0]

Well iiii

[callum tgtt]

Mines a slappy whore warm to

[Phil]

Mines a slappy whore warm to

Ditto

Cp pistons I'm mine, nothing but the best lol maybe it was machined perfectly who knows. But it starts on the button and we will continue our attempts to blow her up over the coming months.

Phil

Edited March 12, 2014 by Philm