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At the expense of sounding like an idiot, I don't understand the "55/88" terminology. I'm used to getting a degrees duration say 270, and then a lift of say 19mm, the above probably translates to the same thing, but I don't know how...
This is how cams were described in the 'good Ole days' & it represents the nominal cam event.
By way of example, take this once popular spec of 30/70, sometimes called a 30/70-70/30.
Inlet opens 30 degrees BTDC & closes 70 degrees ABDC.
The exhaust was just the reverse, IE, exhaust opens 70 degrees BBDC & closes 30 degrees ATDC
You can figure out duration & overlap quite easily from this.
Duration in this case would be 280 degrees
Overlap would be 60 degrees.
Keep in mind that these would be 'nominal' figures, most likely measured at the cam with zero lift, while a more usable set of numbers would be taken at .050" lift.
In more modern times it is possible to see cams with the intake slightly advanced or retarded from the exhaust specs, but with the same duration, & sometimes even with different duration & even lift specs, so more comprehensive figures are needed, but back in the day, the cam grinder just reversed the inlet spec for the exhaust & a two number system was regarded as adequate description.
Some old habits die hard.
Incidentally, a lift of 19mm [3/4"- or .750"] at the cam is bloody impressive.