[jluetjen]

If you have the 36mm S ports, then that changes things significantly. Don't worry about having the top end choked off. It won't happen until you get to the far side of 225 HP. Instead you have to make sure that your cam isn't too mild and as a result never achieve the desired gas speeds at the bottom end! In this scenario you might find the motor lacks the desired torque down low. For example a T cam in this engine will only be pulling 50 m/s of air at its maximum torque speed of 4200 RPM which is slower then any other factory Porsche. An E cam looks like it would be OK since it would be pulling 54 m/s of air at its peak torque speed of 4500 RPM. An S cam pulls 62 m/s at 5200 RPM. The slowest gas speed that I've found in a factory car was the '71 ST which was pulling 55 m/s at 5300 RPM.

Lobe separation is meaningful only in so much as it affects overlap. The other important variable is duration. A short duration cam can have a narrow lobe separation angle, but still have a nicer idle then a long duration cam with a wider lobe angle. For example, both the early E/Solex cam and the S cam have 97 degree lobe separation angles. But as I mentioned earlier, the S cam is noticably wilder then the Early E cam. Why? Because the S has an additional 20 degrees of intake duration it has an additional ~10 degrees of overlap.

You can take a look at the attached where I've summarized a lot of the cams. Note the different overlaps compared to the lobe angles.

Of the 4 cams, Solex, S, GE40 and GE60 I've estimated the following peak torque/HP speeds in your engine.

Solex: 4500+/6500+ Est.
GE40: 5100/6700 Est.
GE60:5500/6800 Est. (More lift and less overlap then S)
S: 5500/6800