Forged Piston Drawbacks
Turbo Mini Forums

Hate to show my age, but back in the day forged pistons had a reputation of being bad for street cars because they grew too much during operation and had a tendency to rattle around in the bores when cold. When I was last paying attention to such things, there were new forged aluminum alloys coming on the market that did not need as much bore clearance. Are any of the modern forged pistons suitable for road use on a Mini?

Technology has improved now and you dont need any extra clearance with forged pistons. I run them myself

I seriously doubt it!

Some of those problems are also down to poor machining, poor spec

Ive had forged pistons in many engines over the last 20 years, and the only ones that gave any concern at all, were the ones where a dipsy machinist left the tolerances too big.

But some of the really good ones these days can run very tight clearances, almost the same as a cast piston.

The only downside, if it is even that, is that they cost more to buy. There arent any others.

Although on the cost point. Forged pistons arent always necessary either. Often cast pistons can be very good. OE Metro turbo pistons are heavy, but they are also bloody strong. IMO in that respect, the only benefit a forged piston will offer is being able to be much lighter with that same strength

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

if you have the cash go for them ...... but if you dont use the cast ones such as OMEGA race piston well proven!