Posted 2019-04-26 10:23 AM (#581371 - in reply to #581300) Subject: RE: 1956 Fury Cam Profiles?
Location: DFW, TX
Based on those generic and secretive "1950s era" valve timing events listed in that article, I'd say the cam has 280/270 advertised duration (35+180+65 intake, 65+180+25 exhaust). Even that doesn't tell us much, when we were raised up on very specific lobe profile details and duration values at a standard .050"
Modern camshafts with "280" advertised duration are commonly around .440 lift and 224 duration. I think those numbers would be a little wild even for a "performance cam" of that time considering it was meant to run in a street driven car with a 303ci 9.25 engine and a Powerflite.
I'm completely pulling this out of my rear, but I would guess it is almost certainly a single pattern camshaft, around .400-.420" total lift and 216-224* duration and 114-112 lsa.
I wish you all the luck in finding the "real" specs of an original camshaft! I think the only way to do that would be to find an engine that you know has the right cam, and then pull it apart and put the degree wheel and dial indicator to it.
Posted 2019-04-26 12:06 PM (#581378 - in reply to #581300) Subject: Re: 1956 Fury Cam Profiles?
Speak for yourself, I was not "raised" on cams being measured at .050 lift. I know that the cam profile numbers can be very different even when duration is listed as the same but I still like to know that number of total duration when comparing cams. According to my FSM, the 57 Fury cam had a total duration of 256-256, lift not given. 17-180-59 In. and 21-180-55 Ex. These numbers are much milder than the profile mentioned in the above article.
Posted 2019-04-26 1:43 PM (#581381 - in reply to #581378) Subject: Re: 1956 Fury Cam Profiles?
Location: DFW, TX
Thanks for sharing those published specs. Yeah, there can be a huge difference in advertised duration numbers if the same lobe is being measured at .005, .010, .030, or .050 lift and that's why they eventually set .050 as industry standard.
It is really interesting that lift values were rarely given in old catalogs and manuals. It's so critical because you get into coil bind, piston to valve clearance, etc. But then again it wasn't fashionable to have ridiculously high lift then, either.
Posted 2019-04-27 3:19 PM (#581416 - in reply to #581300) Subject: Re: 1956 Fury Cam Profiles?
Location: Pacific Northwest
Thanks guys. I'm somewhat of a cam novice. I get the gist just not the technical details of how best to get the most out of it. (Streetable, not a race only profile)
I've got the 303 that i can pull the cam from but i would like to have something to put back in that will work with the dual quad set up i intend to run. If i can find the specs for that cam then I'd like to have one of those ready to go, just in case the one that's in there is not up to the task. I suppose i can run what's in there and see what happens.
Posted 2019-05-01 11:40 AM (#581621 - in reply to #581300) Subject: Re: 1956 Fury Cam Profiles?
Location: Peoples Republic of Oregon
This is not a scientific approach but you can always send your cam to a regrinder and have them check the existing profile and
then decide how much you want to change. Don't go crazy unlees you have the compression to back it up.
Generally, profiles in the 50s were very mild compared to today, or even compared to the 80s oem stuff.
The 256-256 cam noted above is, I think, typical of the time and would equate to about 195@050.
Posted 2019-05-01 7:21 PM (#581642 - in reply to #581300) Subject: Re: 1956 Fury Cam Profiles?
Location: So. Cal
I agree. I think it would be a waste of potential to grind a cam to old specs from the '50s. Bump the compression up to around 9.5 to 9.7 or so, and run a modern profile based on the torque converter you want to run, the cruise-ability, and fuel consumption. The 354 hemi I am building for my '56 Savoy is getting a hydraulic roller cam in it. You won't be able to tell from the outside, but you should be able to tell from the increased torque output of the motor.
Posted 2019-05-01 7:24 PM (#581643 - in reply to #581300) Subject: Re: 1956 Fury Cam Profiles?
Location: Pacific Northwest
Still working on this. I've got an extra set of heads that I am planning on sending out to get some porting done and some bigger valves. It has recently come to my knowledge that THE Cecil Yothers lives just across the pond from me so I am thinking I will give him a visit and pick his brain on the subject. I've heard that he has a factory race car too!