Budget Ford 302 Project (Part 5) Mystery Roller Cam and Valve Spring Checks

Update A: It seems possible that this cam is out of an earlier model year cougar with the non HO engine. I just cant be sure.
I looked for markings on the cam and saw a A - - - on the front next to the distributor gear, but that is all I could see.
In This Video I discuss the difference between measuring duration at the valve vs at the tappet. I then test the valve springs. Lastly, I measure the duration at the valve of the mystery roller cam I have.

[@user-me6op8eo1n]

Keep going love this low buck approach not the mega dollar stuff out of reach for most

[@engine_therapy]

I agree, its about maximizing fun/$.

[@camd266]

The Cougar/Tbird 5.0HO lost most of it's power through a lower, more restrictive intake (lower hood line). The cam "should" be the same as the 5.0HO Mustang...approx 210/210@.050, .444/.444 lift intake and exhaust, respectively...if that did indeed come out of Cougar. I have read that the measured cam specs on the factory ford grinds are all over the place...not very precise production tolerances. There is also a non-HO roller 5.0 that IIRC used the earlier 302 firing order versus the HO firing order. It has lift numbers closer to what you are seeing but your .050 numbers are bigger than the non-HO cam. There should be a stamping or engraving on the end of the cam that should tell you what it is. I didn't see your measured lobe separation angle, the HO cam is going to be around 115-116 degrees, where the non-HO cam is around a 107 lsa. Those springs are even lower pressure than what I have measured on fresh stock replacements. Do they have a lot of miles on them? In any case, I would want more spring if it was mine.

[@engine_therapy]

Lots of good feeback there. I havent taken the degree wheel off it yet, I can check the lsa in the next few days. Remember, those cam durations were measured at the valve and not the tappet. The tappet duration is probably lower. Which end of the cam is the stamping on? I agree about the springs. They probably have way over 100000 miles on them. Do you know of a good low cost replacement? I have looked around but didnt see any that would use the locks and retainers I have. Thanks

[@camd266]

@@engine_therapy Any engravings or markings should be on the end of the cam opposite of the distributor gear. Factory cams and some aftermarket cams are actually measured at what is called SAE duration. IIRC, that is .006" lift at the valve...or .004" lift at the tappet on a sbc or any engine with a 1.5 rocker. Fords with a 1.6 ratio rocker would be measured at .00375" tappet lift. Aftermarket cams...many but not all use .006" tappet lift as their "advertised" duration for hydraulic cams. Isky uses weird numbers like .007" intake/.010" exhaust at the tappet, Crane used typically (but not always) .0045" tappet lift. This is why "advertised" duration is almost meaningless when comparing cams of different manufacturers. On the ford E7TE and many other heads, they use different installed heights on the intake and exhaust. Trick Flow makes a good relatively low cost kit with springs, retainers, locks, seals and a little installed height checking tool. They used to be around $179 last time I bought one (several years ago). They are made specifically for hydraulic roller cams for these and similar SBF heads. If you plan on revving the engine they are a good investment. If you aren't going to beat on it, then stock replacement springs for a 5.0HO are fine. I would replace the locks...they are considered a disposable item and are cheap.

[@camd266]

@@engine_therapy I ran your numbers through the Summit cam timing calculator. I am coming up with a 107.25 or 107.5 lsa. This plus your valve lift tells me that this is the low po 5.0 hydraulic roller cam. But your .050 duration numbers don't match that cam, so I dunno

[@engine_therapy]

@@camd266 Ok, Thanks again!!