Yup. Listed as a non-cobra jet replacement cam for a 428. .428/.431 adv. duration is 273/281, but without the check height thats not much use. Pretty mild cam, not something I would use, but hey, thats just me. edit: sorry, first time I calculated the lift, I used the 1.76 solid lifter rocker ratio, forgot the hyd rockers are 1.73. The numbers showing now are correct.
Thanks! That looks like it is actually a bit better than the factory 428 cam. Has the approx. duration of the 428CJ with the approx. lift of the standard 428 cam (assuming raw lift measured at zero). The stock CJ cam was very mild...same as the '67 390GT cam.
Measuring with my calipers, I get valve lift the same as a 428CJ. Even though its listed as a non-CJ cam, looks like it actually is a CJ cam!
Yep, there were two GT cams. C6AZ-A (standard 428 and '66 GT) and C6OZ-B ('67 GT and 428 CJ). The measured valve lift on this TRW cam is the same as the CJ (480/.490). Duration is approx. the same as C6OZ-B. C6AZ-A was only 256 degrees duration with only .438 valve lift. Edit: I've been told that there were actually three GT cams. Got the specs on the third one around here somewhere. I'll see if I can find them. Edit: I couldn't find the specs, but the number is C6OZ-A. It had less duration than C6OZ-B. There was a running change in 1967. Edit: Found the specs. Exhaust side is .270/.480 (same as intake side...that is, it was not a split cam). All other specs are the same as the B cam.
Hmmm. My TRW Master catalog from 1984 says TM572 is the smaller cam? Do you have a block you can stick it in? Put it in, put a lifter on it, and measure the lobe lift.
I don't have a rocker shaft assembly for it, but I don't think that should give a different measurement than the way I measured it. I measured the radius, then measured across the widest point (highest lift point), and subtracted the radius. That's how Holman-Moody told me to do it when I inquired about an H/M cam that I have that they don't list in their records. It sounds like a parts book error. It would not be the first I've seen for CJ parts (even in the Ford MPC)! A stock replacement cam for the standard 428 should not have that much duration.
We are talking about a difference in lobe lift of less than .030 between the two cams. I guess if your comfortable, its all good, but I would be a little uneasy.
.030? I think that I must be confused. Between which two cams? TM272 .428/.431 valve lift (lobe lift???) according to catalog TM272 .480/.490 valve lift as measured (.052/.059 difference) C60Z-B .481/.490 published valve lift (.053/.059 difference) Lobe lift (valve lift X 1.73) is proportionally increased. For example .052 X 1.73 = .090 more lift. That's a considerable difference when it comes to cam lift. Am I misunderstanding something?
Yes. Its valve lift divided by rocker ratio equals lobe lift, not the other way around. the difference in lobe lift is proportionally decreased. Lobe lift for the small cam in the TRW catalog is .2472/.2491. Lobe lift for the bigger cam is .278/.283. Multiply the lobe lift by the rocker ratio to get gross lift at the valve.
Ah, yes, you are correct. I had my formula backwards. Still, though, .030 lobe lift difference is the difference between a standard 428 cam and a 428 CJ, correct? The CJ cam will make 450 hp on the dyno in a stock build 428 CJ (335 hp was on the B curve) according to what I heard on TV today. That is more than satisfactory for any use I'll make of it (current plan is to put it in a '52 F1 pickup). At any rate, its the cam that came with my 428 PI, and I'm not going to change it. It is what it is. BTW, I've been running 429 CJ's for 32 years, and this is my first FE, so I'm just now learning about FE's. There's still a lot for me to learn.
The TM572 from TRW is the same cam as Wolverine's CS642. This is a "stock" cam for the '66/'68 428. This is a hydraulic deal! The specs on the Wolverine grind are: Adv duration=256*/256* .050" duration intake and exhaust=200*/200* Cam lift intake and exhaust=.253"/.253" Valve lift intake and exhaust=.438"/.438" Lobe centers=Intake/108* - Exhaust/113* L/S=110.5* The events (at .050") are as follows: Intake open= 8* BTDC / Intake close= 28* ABDC Exhaust open= 33* BBDC / Exhaust close= 13* ATDC Thankls, Gary in N.Y. P.S. I believe that Camshaft Machine Co., the parent company of Wolverine, probably ground many of the "EOM" cams for all the car manufacturers??
The specs of the Wolverine cam do not match the specs from the 1984 TRW catalog. The TM572 that I have does not match the valve lift of either (but it does match the CJ cam). The Wolverine specs do match the standard 428's cam specs. I wonder if there might have been several different grinds sold under that part number over the years? I've read that Crane Cams ground many (all?) of the Ford factory performance cams (including H-M's cams). However, my H-M cam has a CM mark. CWC (Campbell Wyant and Cannon) made many (all?) of the blanks for Ford. My TRW cam has a CWC mark. Edit: I just noticed that the box says 1-TM572. The cam is stamped just TM572. I wonder if that "1-" means anything? Edit: Regarding the flathead Ford production time period (circa 1934) - "Campbell, Wyant & Cannon’s principal business was making engine castings for the Ford Motor Company"; Interview with Dr. Ralph Sawyer, by Charles Weiner at American Institute of Physics, New York, March 16, 1967
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