If you are sure its a stock cam, then use 1.4 ratio rocker arms. This will give you increased lift = more air = more power
. To change the cam you have to split the case on type I and type IV motors
.
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1970 T1 W/MassIVe 2913cc RAT/?EFI? w/direct fire (very soon) and 915 trans
1962 SC 1776cc SP 944NA brakes, 993 wheels
VKG