unless your heads are professionally ported you only need the 1.6 on the intake the ex likes the extra exhaust which you have
do you have any flow data
The heads are not ported yet , but will be comparable to a "stage 2" type job. Not going crazy on these. No flow data yet but I do know a stock X head will flow 195-205 cfm on my bench. Targeting a modest flow rate with a nice tight port--245-255 cfm is all that is needed here--maybe less. J.Rob
