I've a mk3 bottom end that needs pistons, while they're being ordered, is there any real world discernible difference in overboring by 1.0 mm, with an engine running a TSR fast road cam, head, but stock valves? Or is it a waste of money? The bores as is, are in perfectly usable condition.
With 1 mm overbore > 2031 cc or good 2% extra volume .... Keep the std bore ... and do some little tweaks on cylinderhead, as that will bring more
Good man Hugo, nice to get my suspicion confirmed by an expert. Now, to try track down the higher comp 10.?:12e/ady pistons.... Most are listed for 2e and AGG, and I'm pretty sure AGG is lower, 9.?:1, it looks to have a deeper bowl, piston skirts are apparently different too. 2E ones being longer.
2E is 10.5:1 and the AGG is 10:1 as std. 2E was in the early EU1 era, whereas the AGG was in the EU2 era where CO2/FE where more stringent. Hence the reduced piston skirt and other improvements.
so I found a set of Nural pistons, on Spareto.com . https://spareto.com/products/8750180050-piston , and my oe ones are also Nural, so win win. How cheap is that??? I don't mind a few weeks wait! Even if I was to go for Mahle or KS, they still offer good value. https://spareto.com/products/034-99-00-piston
https://www.autoersatzteile.de/vw-autoteile/corrado-53i/4793/10629/kolben bloody nora , cheap here too!
