Wossner 9.0:1 Clio pistons

[incy-spider]

Hi guys, what wossner pistons are people using to achieve this compression ratio in an F4R?

I don’t want slappy competition ones either, I have seen there is an option!!

I can get wossner cheap through an engineering friend but currently we don’t know part numbers... can anyone help?

Cheers

 

[bloke]

i'd take quoted ratios with a pinch of salt anyway, most will give few different sizes from 82.5mm-84mm but still give same cr. (sizes are off top of my head by the way)

 

[incy-spider]

i'd take quoted ratios with a pinch of salt anyway, most will give few different sizes from 82.5mm-84mm but still give same cr. (sizes are off top of my head by the way)

I’m aware of the sizes, std size and oversize... what I’m after is what piston would give me 9:1 in my 182 engine... I can get 9:1 Megane pistons but not sure what that would equate too in an f4r!

 

[bloke]

fwir the meg listed pistons give a lower cr used in the clio engine? what power and boost figure you aiming for?

 

[incy-spider]

Chris@efi has mentioned he gets nice results from 9:1 and they retain good drivability... 9.5:1 are good up to 300ish on pump fuel... pretty sure I can get both with one choice of piston by using a 1.3mm gasket for 9:1 I just need to get the wossner part number to order.. apparently there are a fair few options so want to be sure!

 

[bloke]

it was chris i was talking to about meg pistons and sure he said about them being lower cr? wossner not give dimensions on their site?

 

[incy-spider]

 

[bloke]

piston dimensions, with them you canr work out exactly what's what if you want to be bang on 9:1.

 

[incy-spider]

Got them K9475DA

 

[bloke]

cool.

 

[Andyman]

Apologies for the thread crash.
Why do Megane turbo pistons (low comp so sit lower down the bores) hit the Clio valves with vvt yet if you run high compression (sit nearer the valves) Clio pistons they don't ?

 

[bloke]

Apologies for the thread crash.
Why do Megane turbo pistons (low comp so sit lower down the bores) hit the Clio valves with vvt yet if you run high compression (sit nearer the valves) Clio pistons they don't ?

think valve cut outs are different?