(Login zgwforum) Member from IP address 188.8.131.52
Does anyone have a Ford car shop manual listing inclusive of the BOSS 351?
My 71 shop manual has no references.
It has 302
302HO(referred to as BOSS in the column headings)
I am interested in the camshaft specs. I have seen several numbers posted in various articles, and even discovered there was an error in the manual calculating theoretical valve lift due to the use of a 1.6 rocker arm ratio instead of 1.73.
Simply interested in some "official" documentation.
I own all the manuals. The Boss 351 (actuall 351 HO) never made it in to an engine manual. As you already mentioned, the 1971 manual includes the 302 HO, because when the 1971 manual was being assembled they thought the Boss Mustang was going to be equipped with a 302 HO, the 351 HO was a last minute change of plans. The 1972 manual has 351 HO data, but its for the 1972 version of the 351 HO ... lower compression & different cam.
There was no error in Ford literature regarding rocker arm ratio and calculated valve lift. The error was in the mind of the internet hero who started that rumor. Ford's published lift figure is NET LIFT, lash is deducted from Ford's figure. Since they used the same cam specs, the camshaft data for the 302 HO cam is identical to the 351 HO cam.
As far as I know nobody is reproducing this camshaft, and as far as I know its impossible to find a grinder that will grind a camshaft with anything greater than 115° lobe separation angle. There was a hydraulic version of this cam in the 1970s, and it is still available from a few suppliers such as Speed Pro. I have a cam spec I call a Boss 351 cam, that will provide similar powerband and drivability, but using modern lobes it will actually make more horsepower. It can be spec'd for hydraulic flat tappet, hydrualic roller tappet or mechanical flat tappet. If you're interested let me know.