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Discussion Starter #1
I found my oil leak and the 302 is going back together. I am baffled
though following degreeing the new camshaft I decided to install.

Readings are as follows head on, head gasket installed, snugged down, "O" stamped rockers @ .026".
Cam installed straight-up cloyes double roller chain
ICL: 79 deg @ .05 + 153 deg @ .05 = 232 deg/2 =115.5 ICL
Cam card lists ICL at 110 deg. I think the cam is ground wrong?
LSA: 115 [email protected] .05 + 113 [email protected] .05= 228 deg/2=114 LSA
Looks good
Timing events:Exh starts open 39 BTDC, Exh closed @ 93 deg BBDC
Intake opens 95 deg ABDC, Intake closed 34 deg ATDC

Pic of cam card


Todd
 

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Is the cam ground wrong or is it a typo on the card?

Are the specs on the card identical to the 30-30 cam?

I know you are careful with your engine assembly.

alan
 

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I have run into Summit cam cards that were bogus, but your deal seems you just need to advance the cam some. Finding a gear set 5 or 6° out isn't unusual at all.

On checking events, how are you doing that..... because if you are doing it on the lobe vs on the valve retainer you have the rocker ratio you need to take into consideration. And you need to know how it is specced,,,,, at what lift and where. That should all be available at Comps site. I haven't degreed one today so I won't act like I remember:).

You know Comp has their own flavor of breakin oil for flat tappets now, eh?

http://www.compcams.com/information/whatsnew/NewsDetails.asp?ListHistoryID=592413442
 

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Todd,
Looking at the cam card it looks like the opening and closing specs are at .016" lobe lift. You really need to be checking the cam on a lifter, not out at the cylinder head. Try it again and see what you get. I have never degreed a cam by measuring anywhere but on the camshaft itself with a lifter or cam degreeing tool that goes in the lifter bore.
 

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Todd,
The other thing is, try measuring the centerline going .050 either side of max lift on the intake lobe. It could possibly be an assymetrical grind in which case your method will not work.
 

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Todd,
I dont think you can check the intake centerline accurately doing it from the .050" lift points. Try doing it at max lift on the lobe + and - .050" and see what you get.
 

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Todd,
No, you can still use the lifter but ..... :
1. Put your dial indicator on the lifter.
2. Turn the engine until you are at max lift on the lifter, "zero" your dial indicator.
3.Back up about .070"
4. Start turning forward again and record the number on the degree wheel when you are .050" before max lift
5. Keep turning until you get to max lift then keep going until the lifter drops .050" then record that number.
6. Add the two numbers together and divide by 2. You should get 110 if the centerline is correct.

Make sure to keep a little pressure on the lifter to make sure it is following the cam.
Try it and see what you get
 

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Bill,

Please come right out and tell us what the CC wannabe 30-30 cam really spec's at b/c I'm reading from you that's NOT a 30-30 cam at all.

How far off am I b/c the 30-30 is like 346 per GM/314 per WBR/ and 304 per the late Pat Kelly/254, 114/112, .455" net lift w/ .030" hot lash.

And this is why the old Isky Z-30 cam does better, imho, b/c it is 290/250, 108/108, .450" net lift w/ .030" hot lash. BUT I gotta admit that it is a "knarly" SOB w/ 11 to 1 CR. in a hopped up 327.

pdq67
 

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Discussion Starter #12
Bill;
Rechecked the numbers and the following observations apply.
Full Intake lobe lift at lifter, dial indicator set to 0.00"
ICL: @ .005" 128 deg + @ .005" 97 deg = 225/2 = 112.5 degrees
Recheck ICL at .050, 162 deg + .050, 63 deg = 225/2 = 112.5 degrees
See TDC recheck pic
See ICL pic
 

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Todd,

Looks like it is off 2 1/2 deg. Might be the cam, might be the timing chain set, might be the keyway in the crank. I would put a 3 degree bushing in it and call it a day.
 

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Tod,
You will either have to get one of the 9 keyway chain sets, or drill the cam sprocket for an offset bushing, or ........ and I hate to say this .... just leave it alone, you will probably never notice the difference.
 

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Discussion Starter #17
Bill;
I understand, as with the ICL at 112 degrees and the LSA at 114 I have 2 degrees advance. So adding 2 degrees more would get me to the manufacturers desire to grind them to 4 degrees for better performance down low.
Decisions decisions.
Bill thanks for all your help

Todd
 
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