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Re: Why degree a camshaft?
[Re: markrr]
#1444016
05/28/13 11:52 PM
05/28/13 11:52 PM
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Joined: Aug 2003
Posts: 43,084
Bend,OR USA
Cab_Burge
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I Win
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Posts: 43,084
Bend,OR USA
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Quote:
I have a 440 with a Compcams CRB 280H-10 camshaft. I have read that I need to degree with a degree wheel this cam. What will degreeing do for me?
Also, with my stock pushrods and stock non adjustable rockers and this cam should I measure the lifter's preload?
Degreeing the cam will insure that the cam is installed where it will run the best at, I have seen timing sets that had the dot on the cam gear be off as much as 12 degrees. A motor that has a cam advanced or retarded 12 degrees won't run worth a hoot, take my word on that, been there done that   some of us learn the hard way, sometimes more than once  You don't want to go through that  As far as the pushrod preload you can check that very easily with the intake valley cover off, time or degree the cam and then rotate the crankshaft so the piston is at TDC on the fring stroke, the cam gear dot should be real close to the 12.00 O clok position, straight up  Now installed the two #1 pushrods and rocker arms(leave the others out for now  ) and look at the distance between the lifter cup that the pushrod is riding in and the lifter cup retainer  The bad thing about the stock Mopar rocker arms and shafts is that they vary on the ratio a bunch 
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Why degree a camshaft?
[Re: markrr]
#1444018
05/29/13 12:16 AM
05/29/13 12:16 AM
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Joined: Aug 2003
Posts: 43,084
Bend,OR USA
Cab_Burge
I Win
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I Win
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Bend,OR USA
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Quote:
So a camshaft, possibly mine, may not be right from the manufacturer? Great. Degreeing a cam will discover and correct this?
My motor runs like crap and nothing I do makes it better. I'm thinking of trying to figure out how to degree a cam. Maybe I can come up with something.
Me thinks you have already found out the hardway on not degreeing a cam  Sorry for your pain Now, get it degreed  Let us know your results BTW, it isn't usually the cam that is off, but it can be Did you replace the timing set or reuse the old one?
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Why degree a camshaft?
[Re: markrr]
#1444020
05/29/13 12:41 AM
05/29/13 12:41 AM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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Quote:
My motor runs like crap and nothing I do makes it better. I'm thinking of trying to figure out how to degree a cam.
did you have a prior post on this? if so could you post a link to it? If not more details on what's going on with it? I would do a compression test before you open it up just for a baseline. I would suggest checking exact TDC before anything. After you degree your first cam you'll be surprised how easy it is. You're pretty much just finding the degrees on the 'wheel at which point the intake lobe is at it highest point (intake centerline "ICL") & seeing how many degrees that is away from piston TDC which is zero on the 'wheel & comparing that to the specs on the cam card. Holler how it goes/what it ends up being. EDIT Easy degreeing; This'll be easier & be within 1 degree. Buy/make the piston stop tool & screw it into the #1 spark plug hole & confirm the dampener TDC slit is at exact piston TDC. Then remove it & with the #1 piston on TDC "compression" verified by rotor on #1 plug wire or timing chain gear dots on 12 & 12 o'clock or feeling for compression on the #1 plug hole then with the dampener slit on zero then move the crank slightly back & forth & both of the #6 cyls' lifters will be moving as you move the dampener back & forth slightly from TDC & at that point see if the dampener TDC slit is at zero on the timing tab with the lifters at EXACTLY the same height (dial indicator) & if so the cam is degreed within 1 degree of being correct & the problem is elsewhere. This required a TIGHT timing chain to work.
Last edited by RapidRobert; 05/29/13 04:30 AM.
live every 24 hour block of time like it's your last day on earth
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Re: Why degree a camshaft?
[Re: RobX4406]
#1444023
05/29/13 09:34 AM
05/29/13 09:34 AM
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Joined: Apr 2004
Posts: 965
S.W. Pennsylvania
markrr
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super stock
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S.W. Pennsylvania
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Quote:
When you see timing sets, when lined up dot to dot, are 8* retarded, it's hard to fathom why people don't degree cams.
I did not know this  .
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Re: Why degree a camshaft?
[Re: srt]
#1444025
05/29/13 10:09 AM
05/29/13 10:09 AM
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Joined: Aug 2011
Posts: 1,083
SE PA
Yellow Fever
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SE PA
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HYDRAULIC FLAT TAPPET: For 9:1 to 10:1 compression. 383 needs 2500 stall. 440 needs 2000+ stall. Use 700-800 CFM carburetor, headers, 3.91+ gear. "The miss doesn't go away when I rev the motor and it seems to be getting worse over time. There's always been a slight miss that's now getting worse." Do a leak down test, that will tell if any valves are hanging open. You'll also need a timing set that has the ability to be degreed. I would check to be sure the cam didn't wipe during break in.
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Re: Why degree a camshaft?
[Re: srt]
#1444026
05/29/13 10:15 AM
05/29/13 10:15 AM
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Joined: Apr 2004
Posts: 965
S.W. Pennsylvania
markrr
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Quote:
not being a smartasz here, are the plug wires installed in the correct order?
Unburned fuel in exhaust indicate another issue. Also do you have another set of wires and plugs to install?
I've been racking my brain here over this and was just thinking the same thing about the plug wires. I will check them later today. I do not have another set of wires and plugs. The plugs are only about 1 month old.
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Re: Why degree a camshaft?
[Re: markrr]
#1444027
05/29/13 10:19 AM
05/29/13 10:19 AM
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Joined: Oct 2003
Posts: 4,003
South Park, Pa.
68LAR
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South Park, Pa.
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My Normally a cam "out of time" will not cause a miss. It may not run right, but usually will not miss. Find out why the engine is missing and you'll get the power you're looking for. As suggested, do a leak down test or at least a compression test with the carb throttle blades wide open. Pull your plugs and see if one or two are fouled. Check your firing order. What kind of ignition are you running. There have been issues with the MOPAR orange boxes. Any of these can cause a miss. You may have to have your distributor worked on to "quicken" the advance and maybe have a little more initial, but only after you find the miss. Good luck. If you need help, call me. Larry
4 speed street legal. Best time 10.99 @ 124 mph on 93 octane pump gas @ 3926# total weight
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Re: Why degree a camshaft?
[Re: Yellow Fever]
#1444028
05/29/13 10:23 AM
05/29/13 10:23 AM
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Joined: Apr 2004
Posts: 965
S.W. Pennsylvania
markrr
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Quote:
HYDRAULIC FLAT TAPPET: For 9:1 to 10:1 compression. 383 needs 2500 stall. 440 needs 2000+ stall. Use 700-800 CFM carburetor, headers, 3.91+ gear.
"The miss doesn't go away when I rev the motor and it seems to be getting worse over time. There's always been a slight miss that's now getting worse."
Do a leak down test, that will tell if any valves are hanging open.
You'll also need a timing set that has the ability to be degreed. I would check to be sure the cam didn't wipe during break in.
The car is a 4 speed with 3.54 gears and no headers. Headers alone cannot improve how bad it's running.
As far as a wiped out cam, I'll be checking for this when I take everything apart...again.
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Re: Why degree a camshaft?
[Re: markrr]
#1444029
05/29/13 11:10 AM
05/29/13 11:10 AM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
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Lincoln Nebraska
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Tho I'm a firm believer in k.i.s.s. & checking TDC & a basic compression test is always a good idea I'm gonna go out on a limb & opinionate that the long block is healthy & that includes the cam timing & that the the prob is: ECU going bad, plug wire order wrong, VACUUM LEAK, rotor phasing
live every 24 hour block of time like it's your last day on earth
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Re: Why degree a camshaft?
[Re: RapidRobert]
#1444030
05/29/13 08:45 PM
05/29/13 08:45 PM
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Joined: Apr 2004
Posts: 965
S.W. Pennsylvania
markrr
OP
super stock
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S.W. Pennsylvania
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Quote:
Tho I'm a firm believer in k.i.s.s. & checking TDC & a basic compression test is always a good idea I'm gonna go out on a limb & opinionate that the long block is healthy & that includes the cam timing & that the the prob is: ECU going bad, plug wire order wrong, VACUUM LEAK, rotor phasing
I just did a compression test and all 8 cylinders are darned near then same readings. I rechecked the wires and they're right. Is there any way to test an ECU? And if I measure the lifters' preload what should the range be?
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Re: Why degree a camshaft?
[Re: RapidRobert]
#1444032
05/29/13 10:50 PM
05/29/13 10:50 PM
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Joined: Apr 2004
Posts: 965
S.W. Pennsylvania
markrr
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Compression numbers are all around 155 to 160.
I do not have another ECU to try.
Last edited by markrr; 05/29/13 10:52 PM.
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Re: Why degree a camshaft?
[Re: markrr]
#1444034
06/01/13 10:58 AM
06/01/13 10:58 AM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
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Lincoln Nebraska
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The even/fairly decent comp readings tell you the long block is healthy, I dont like to shotgun parts to a car to diagnose so I wouldn't suggest buying an ECU just to guess & I'm thinking the ECU may be OK tho nowadays keeping a spare makes good sense with their track record for breakdowns. With the dist cap on make a mark on the top of the dist metal perimeter rim at the center of a cap terminal bulge & pick the bulge slightly to the left CCW of where the rotor is right now then turn the crank with a 1&1/4" socket/breaker bar clockwise slowly/carefully till the magnet is dead even with the next tooth then at that point see if rotor is pointing at the center of the mark you made on the dist metal perimeter or very close, which is rotor phasing & if it's very off post how far & which way (vac adv shifts it CW from it's at rest location on a big block). I'm assuming the plugs/wires are in good shape & routed 1-8-4-3-6-5-7-2 CCW. I keep coming back to a vacuum leak & it is less noticeable at higher rpm's since there's less time between each firing so that masks the problem. Myself I think I'd pull/replace the valley pan which on a BB ain't hard to do & use Permatex #1 in the toothpaste like tube lightly/evenly around each of the 8 port openings on the valley pan & check if bolt holes/ports are matching (on the slope). Maifold may not be dead flat. Good visual & go from there.
live every 24 hour block of time like it's your last day on earth
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