28-10-2015, 10:31 AM
What turbo engine? You've still got 10.4:1 compression with a matching S16 head and more with a GTi-6 one.
S16 pistons are flat topped and not slightly dished like GTi-6 (or with a shallow bowl like the detuned J4R engine) hence still fairly high compression despite sitting 1mm down the bore.
The 2.0 8v turbo (XU10J2TE) pistons have a sizeable dish in them and the chambers in the head are a fair volume as well, hence they're down in the 8's compression wise.
If you particularly want a low compression 16v for forced induction then I imagine that using a J4R bottom end with an S16 head would give lowish compression somewhere in the 9's (CBA to work it out)
S16 pistons are flat topped and not slightly dished like GTi-6 (or with a shallow bowl like the detuned J4R engine) hence still fairly high compression despite sitting 1mm down the bore.
The 2.0 8v turbo (XU10J2TE) pistons have a sizeable dish in them and the chambers in the head are a fair volume as well, hence they're down in the 8's compression wise.
If you particularly want a low compression 16v for forced induction then I imagine that using a J4R bottom end with an S16 head would give lowish compression somewhere in the 9's (CBA to work it out)
1990 Peugeot 205 GTi 1.9 // 1991 Peugeot 205 GTi 1.9 16v // 1992 Peugeot 205 GTi 1.9 // 1999 Peugeot 306 HDi Estate