Techniclly they are forged, they are however flat top pistons.
I thought I explained that, in short they dont have the usuall valve indentations, reason why is so I can use a 1mm head gasket and keep compression at a reasonable level.
So in short the pistons I have will cop just as much punishment as others on the market, just offer lower compression than the usuall forged items.
So I compensate with a smaler/thiner headgasket to make the difference. Make sense?
Why do it this way, well flattop pistons offer faster ignition, more efficient, ummm how do you say like more even ignition.
Hard to explain withoutusing my hands But the GT500 cars run flattop pistons, gives more torque down round the 1000-2500rpm range.
Disadvantage, hard to find and costlly. I got mine through perfectrun they are Jun items, I bought mine when they made discontinued at $1400 AUD.
Which is a lot less than they usually sold for. I think they were just trying to get rid of the last couple of sets. I guess you spend about $1400 on pistons anyway.
But yeah, the pistons are not cast, they are forged in that sense. Just not the usuall design tops.
Side note, the manifold I got was for mok-up purposes. It was sent away and reconstructed and re-inforced before use. I also had it heat treated and crack tested.
I was going to go a 6boost manifold, but he had supply/demand issues at the time and I could not wait. Doing it the way I did it was costlly tho.