Rgx Vs Rgy 2.0 8V Turbo Pistons

[cybernck 400 1 Cars]

From what I've read on here, RGX is supposed to be dished and with 8.5:1 c/r,

while RGY should be shorter, with flat crowns and 8:1 c/r. However, I've got

the data of 40 mm being the piston's compression height for both versions,

which is conflicting data.

 

Has anyone got a photo of RGY vs RGX pistons or of RGY bottom end at TDC?

 

By the way, ultimately I need to know if any of 2.0 8v Turbo pistons will

clear 16 valves (with standard 2.0/S16 rods) or not .

 

And a bonus question - does a Mi16/S16 head fit a GTI-6 block straight on?

 

Thanks, Nikica.

[Slo 283 1 Cars]

Ive had 4 605 svti's with the RGY engine, of these I removed two of the heads over time and both of them had flat piston crowns,

[cybernck 400 1 Cars]

OK. At least we got something straight. It means the compression height data takes into account

the lowest point of the piston, with RGX having raised edges compared to RGY, for slightly higher

compression ratio and better squish.

 

Still, that means none of these pistons are suitable for use with 16v head, as T16 pistons are also flat,

but sit 4.5 mm further down the bore (compression height of 35.5 mm.

[Razkin 0]

RGY has 8.5:1 with flat pistons that are not flush with deck in TDC. (I thought they cleared a standard 16V S16 head, but I am unsure about that, I did measure the difference between RFY/RGY/RGX pistons well over a year ago, but cannot seem to find my measurements)

RGX has 8.0:1 with dished pistons that are flush with the deck in TDC.