I will keep this as a sticky, as this is probably the most asked question in here. If you dont see your motor, make a post and i will add it to the list. All assuptions are based on stock motor, with midsize T3/T4 turbo, and minimal fuel and timing upgrades. if you need something more specific let me know and ill help you out.
Honda/Acura:
d15- 7psi
d16- 8psi
b16- 8 1/2psi
d17a2- 7-8psi
B18b- 10psi
b18c-8 1/2psi
k20- 8psi
k24- 6-8 psi
f23- 8psi
f22- 8psi
h23- 8psi
h22- 8 1/2psi
b20- 6-8 psi
Nissan
k24- 8 1/2psi
sr20de- 8psi
sr20det- 12-14psi
vq20de- 6-8psi
vg30- 10-12psi
vq35- 8 1/2 psi
rb20- 8-10 psi
rb25- 12-14psi
rb26- 15-18psi
Mitsu
4g63- 8-10psi
4g64- 8-10psi
4g92- 6psi
6a12- 6-7psi
420a- 8psi
Mini cooper
standard motor- 5-6psi
Toyota
2jzgt- 8 1/2 psi
2jzgte- 15-18psi
4afe- 6psi
7afe- 6-7psi
1zzfe- 6psi
xa-xb scion standard motor- 6psi
(ScionTC) 2azfe- 8 1/2 psi
Mazda
zmd- 6-7 psi
fsd- 6-8psi