I seem to recall years ago reading somewhere the the assembly time at the factory for one of these motors was huge because of the complexity of properly setting up the cam timing. What is the approximate assembly time now vs a pushrod 356 motor?
My budget never allowed me to move into Fuhrmann´s engines but I certainly learned everything there was to learn about the 616 type pushrod engines for my 912 and I fondled my first big bore kit from Japan like crown jewels when it was time to rebuild! I once did see a four cam on an operating table and was amazed not to find reliable marks on the crown bevels so as to even have a chance of getting the cams set to match the drive shafts...not a mark anywhere... my heart sank and I stuck with the 616s and never regretted it!
In my younger years I was crazy for four cam cars( had a number of them) but as time progressed and they all got soaked up by fat cats who needed a place to sock away all of their loot, they drove the price of 4 cams to obscene levels!Now I look back and at what has become an insane obsession.Hundreds of thousands for an engine that makes hardly more than 150 hp and weight in at almost 400lbs( some versions) is just plain stupid! Not to mention how delicate they are. Fuhrmann had a neat idea, but he sure fell short of what the Dr. designed in the old 25 and 36hp!
As a small boy in CT I followed Porsche and the 550 and the 4cam became my favorite. When I moved to Tucson in 1964 I happened to be at a Porsche dealer where I ran into a person replacing his 4cam in his 356 for a push rod. That could have been a roller bearing model but when I asked him why he said the car was more drivable with the push rod engine. I had a S90 later and I must say I do enjoy the C more than the S90. Can you address why people liked the push rod more than the 4cam? I transitioned to 911s in 1966 because of the smoothness and high reving of the engine but perhaps the 4cams that were being replaced were those without the cam balanced and they didn't provide that much more power.
In general the higher the state of tune for any given engine, the shorter the operational life span and more functional compromises in street operation. The Hirth roller crank engines were race engines. They would quickly flatten the crank roller bearings when lugged around at low rpms. These were very expensive cars, and road customers were not pleased with the very expensive repairs. I ran the 1600 Normal 60 horsepower( Die Damen) , the 1600S 75 horsepower, and the S90 90 horsepower in the 356’s. The 1600 Normal stayed in tune and had a considerably longer service life than the hotter variants. Back then 70,000 miles was typical rebuild time for a 1600 Normal. My girlfriend could blow up a Porsche motor in a couple weeks. When the rod went through the case we would just weld it up and replace the damaged internals. Why not? She would soon blow it up again ignoring the tachometer..she lived hard and died young, like those motors.
My understanding is that aside from premature wear, is that plain bearing engines produced more torque than their roller bearing counterparts. So for everyday driving, the seat of your pants sensation would definitely be that of more grunt down low in the RPM range.
