I had the
oil cooler blocked off on my BBC Cobra and it made 260, at the track, unblocked it and it came back to 220.
Morris, will have a look at your website, Have looked at a lot of Muscle race cars here in NZ, some with 900bhp, they run a piddly wee breather out of one valve cover and use the scavenge to do the rest, and appear to have no problems!
Surely with the -12 out of the valley cover, and a -16 going back to the tank sucking will cover the pressure. Your recommendation to take one from the old fuel pump cover is a good idea, if I find the others not enough, or I could take one out of the valve covers (which I have just welded up the holes) you have got me thinking now!!!
Your comment about two 1 1/4" breather tubes for the motor, is this in addition to what I have mentioned I intend on doing, thats a lot of breathing?