36171587-5 Heads...

My 587 flow figures FWIW.

2.02 intake valve - My porter was a bit "shy".

100 - 75
.200 - 142
.300 – 170
.350 - 195
.400 - 219
.450 - 231
.500 - 240
.550 - 243

Exhaust are a bit "soft" -

.100 - 55
.200 - 114
.300 - 130
.350 - 140
.400 - 142
.450 - 145
.500 - 148