Purple shaft id please

Bill fury

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Anyone know what purple shaft cam this is from these numbers? Pulled out of a 440 years ago.
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Thanks.
 
The referenced cam looks to have the same specs as the 383/335 and 440/375 engines of the past.

FWIW, in the beginning, there were about TWO original "Purple Shaft" cams. The 284/284 Street HEMI cam for non-HEMI B/RB engines, which was quite popular when it came out in the later 1960s. The companion to it was the more radical 292 .509" lift cam. There might have been a mechanical cam or two, but these (from my observations) were the main ones. All available through the Hustle Stuff/Direct Connection/Mopar Performance sections of Chrysler's OEM dealer parts supply chain. Or a very limited number of Direct Connection "jobbers", at the time.

Sometime in the later 1980s, Mopar Perf sought to expand and capitalize on the famous "Purple Shaft" designation and (seemed to) co-opt an aftermarket brand's cam selection for Chrysler engines. The cams in THOSE listings were varied and went from small to large in about 6 steps. All with more-aftermarket-like lobe separation angles (smaller than stock, usually 110 degrees). To me, this took some of the "value" from the "Purple Shaft" name. BTAIM

In one respect, I'm glad to see Chrysler embrace the earlier OEM HP cams into this program. It makes them easier tp get and gives them the credibility they deserve. BUT you also have tp know their specs to find them. The 340/275, plus the 383/335 and 440/375 cams are there, indicated by their particular advertised duration and valve lift specs, in addition to some of the more-aftermarket style came. A situation of "have to know what you're looking at" to know what's what.

One interesting aspect of these things is that now, we have definite .050" lift duration figures to deal with. As some might know, such specs didn't start to apper until the 1980s. Direct Connection/Chrysler engineer Larry Sheppard, when asked about the .050" lift duration of the Chrysler OEM HP cams (at a Mopar Perf seminar on "new products" at Mopar Nats) stated that, roughly, the advertised duration x .80 would resullt in "a ball park number" for comparison. The OEMs used the SAE specs to measure valve duration and that was all. The .050" lift duration spec came from the aftermarket as a common measurement with which to use for comparison purposes, which was a great idea, all things considered.

Just some things I wanted to mention, relating to the history of the "Purple Shaft" cams in the Chrysler HP parts (Hustle Stuff, Direct Connection, and Mopar Performance) realm of things, over the years.

Enjoy!
CBODY67
 
Measure lobe height and multiply by 1.5 then match it to cams list in Mopar performance catalog.
Those numbers usually pretty useless.
 
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