Hi i just thought i would post this up to help the people who cant visually tell the difference between factory rb30 turbo pistons and the factory na pistons.
As you can see the turbo pistons (from an A8 motor) on the left are dished and this is to bring the compression ratio down to 7.8.1.
The pistons on the right are standard non turbo rb30 pistons which are in the majority of vl's and in all R31 skylines except of course those that have had a vl turbo motor conversion. As you can see they have a raised surface that is much the same shape as the vl turbo pistons except that it is raised not dished. In fact when i put the na pistons upside down on top of the turbo piston i think it nearly fit perfectly into the dished area. The comp ratio for rb30 non-turbo pistons is 9.0.1. hope this helps.
you dont need to change pistons when converting a n/a to turbo.
1988 VL Berlina turbo 5 speed
http://forums.justcommodores.com.au/...ml#post1446411
1987 VL SL turbo 5 speed ~STOLEN~
http://forums.justcommodores.com.au/...ed-manual.html
I don't understand what you are directing that at.. was that just a general statement?
Everyone knows that you don't need turbo pistons to convert your car to turbo. you will just have a higher compression turbo motor. this thread is just to show the visual difference of the turbo and non turbo pistons so anyone looking to buy a genuine turbo motor know what they're looking at if they have no idea.
The engine number will determine if its a turbo motor.
But good idea to show newbies to help explain and show newbies about turbo conversions and compresion ratio
Yeah exactly. this should help since you have some people who are dodgy and rebuild blown A8 motors with na pistons, try to re-stamp A6 blocks, or try to advertise and sell series 2 na blocks as turbo motors for premium prices to those who are unaware of the factory stamping system.