[TCracingCA]

Talking to the potentially fastest marques up there!

I have slammed like the RGruppe movement a little, but highly respect the enthusiasm and the taste level. The cars have personal style and character. So I am trying to think about how fast a Porsche could have been, back in the day. Most of the modern guys get a 2.7 or 3.0, or 3.2, 3.6 and drop essentially a big block with bigger 46mm valves into early cars or long nose conversions. Maybe the Cams got changed to an RSR or 906 grind, and then you have induction and exhaust.

I have every Porsche parts catalog known to mankind, and in like the Vasek Polak, you have pictures of cool things to buy, but the engine section was limited in component sections for upgrading the engine build. The rest of the Catalog is very much like Andial, where the special rockers, or rods, or pistons didn't really have a description that allowed the casual guy to know the part was hot. You had a Porsche sequence number and had to be in the know, to know that was the hot part. Guys weren't porting heads really, but the actual trick for more flow, was to buy the low horsepower, less stressed cylinder heads, as they had more meat to grind out of the floors of the ports. Otto’s did our twin plug conversion on our 67 911S! Don't know too many guys outside of IMSA to run 49mm valves and the matching pistons. You pretty much just port match the intakes. The twin plug heads were needed, because of the big piston dome. Most guys couldn't tune twin plug systems, especially at 8K type speed.
Suspensions in the 1970s, was growing tire size, and increasing torsion bars or sway bar size. Then you got a better married shock/spring unit, to better track the road. Maybe if you were a real racer, you had solid bushings of some type.

The beauty of the Japanese car engines like the 510/240 Zs was the crossflow design like the old Offy engines. Intake in one side, and exhaust out the other. Very efficient. The little Mini Cooper engines have turbulence and flow complications due to intake and exhaust in the same side. Thus the flow is flow thru. You had excess duration overlap, not an ideal set up, for optimum horsepower. Even VW or Porsche pancake engines flow across the heads. PS- I have seen a few dummies firing off the wrong side of the twin plugs on a number of Porsches.