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Reed cam prep/oil hole location
https://slantsix.org/forum/viewtopic.php?t=34396		 Page 1 of 2
Author:  Bren67Cuda904 [ Thu Mar 19, 2009 3:01 pm ]
Post subject:  Reed cam prep/oil hole location
Just received the new cam the other day and looking at the cam card I am confused. The cam shows a shorter duration at 50 but the overlap is 10* more. I thought is was supposed to be 2* or there abouts.
Also want to verify the the oil holes are in the correct place. One thing that caught my attention is pictured below.
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Note the card above says 20* overlap while the card below says 30*. What am I missing here? I was tring to minimize the overlap to cut down on exhaust smell.
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The picture below if you look closely you can see that the journal oil hole intersects with the for/aft hole.
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The hole (red arrow) is drilled all the way through. Wouldn't this let the oil pressure just blow down and not push its way to the rocker shaft?
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Just by eye balling, does it look like the holes are "clocked" correctly?
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Someone was talking about prepping the cam gear to help prevent wiping out the oil pump gear. I added some colored lines to help with discussion.
Author:  Joshie225 [ Thu Mar 19, 2009 3:36 pm ]
Post subject: 
So they drilled a hole all the way through the back of the cam that intersects with the oil passage? Send it back. You'll get no oil to the valve gear.

You need to know the valve event checking height to see if the overlap numbers are comparable.
Author:  Exner Geek [ Thu Mar 19, 2009 3:59 pm ]
Post subject: 
Unless the hole through back of the journal intersects the oil passages drilled in the surface of the journal it is okay. Its purpose is to prevent oil pressure building up behind the cam and pushing it forward. The best way to check the angle of the intersecting oil passages that feed the rocker shaft is to slip a rear cam bearing over the journal. The holes do not have to line up exactly, but if they are too far off, you can champher the entry to the passages in the journal to improve oil flow. For some reason the indexing of these holes is not very consistent and should always be checked.

Terry Littlejohn is the one who recommends breaking the sharp edges on the drive gear teeth. You can do this carefully with a dremel grinder. This may or may not prevent an oil pump gear failure but it is eazy to do and won't hurt anything. I always do it.
Author:  Bren67Cuda904 [ Thu Mar 19, 2009 5:33 pm ]
Post subject: 
Quote:
Unless the hole through back of the journal intersects the oil passages drilled in the surface of the journal it is okay.
I does intersect. Plugging one little hole in bearing surface with finger and blowing through other little hole on bearing surface causes venting through larger hole which is drilled clean through.

In terms of gear prep, you would grind slightly the RED line's hard edge just to take off the corner?
Author:  bigslant6fan [ Thu Mar 19, 2009 5:54 pm ]
Post subject:  cam
I had that problem with a S/6 cam from another suppler,Your right,send it back.
Author:  Bren67Cuda904 [ Thu Mar 19, 2009 6:05 pm ]
Post subject: 
I hate it when businesses don't answer the phone during business hours. I've been trying to call Reed Cams all day.

I also would like to discuss the numbers with them. Since they need to grind another one I'd just like to be sure I am getting what I want. Hate to send back a second cam just because its ground wrong.
Author:  emsvitil [ Thu Mar 19, 2009 6:38 pm ]
Post subject: 
Wait a minute.........

If the rear of the cam resides in a cup, the rear hole intersecting the oil passage shouldn't matter.

The cup will fill with oil, then the oil's escape path is the oil passage to the valves..........
Author:  SlantSixDan [ Thu Mar 19, 2009 6:43 pm ]
Post subject: 
Make sure they understand your goal about minimizing exhaust smell, so they will grind you the right cam.
Author:  Bren67Cuda904 [ Thu Mar 19, 2009 7:15 pm ]
Post subject: 
Quote:
Make sure they understand your goal about minimizing exhaust smell, so they will grind you the right cam.
I had that conversation with them already. I was a bit surprised to see the old cam has 20* and the new cam has 30* of overlap. I must be reading the cards wrong or there is a typo. If not it would seem that the exhaust smell would be worse with the new Reed cam.

Thanks for the input guys
Author:  Exner Geek [ Thu Mar 19, 2009 7:20 pm ]
Post subject: 
I think Doug or some one else had this same problem with the rocker oil feed passages intersecting the fore & aft hole. I think whoever it was plugged the big hole, redrilled the oil feed holes, then drilled another fore and aft hole in a different location. These cam billets are really getting bad, it has become one of the biggest causes of problems with our engines.

Yes about where to smooth out the edge of the gear. Looking at your timing card it looks like you do have 2 degrees of overlap at .050, the larger numbers must be at less lift. I'd consider 2 degrees at .050 to be guite minimal, do you konw what you had at .050 before? I haven't been following your project so maybe you have already discussed this.
Author:  CARS [ Thu Mar 19, 2009 9:20 pm ]
Post subject: 
Exhaust smell? Are you referring to overlap? (intake is open while the exhaust is open and fuel is being pulled out the exhaust?)
Author:  Bren67Cuda904 [ Fri Mar 20, 2009 6:10 am ]
Post subject: 
Quote:
Exhaust smell? Are you referring to overlap? (intake is open while the exhaust is open and fuel is being pulled out the exhaust?)
yes
Author:  Al T [ Fri Mar 20, 2009 11:07 am ]
Post subject:  Apples to Oranges
Looks to me like the Howards cam numbers are the number at 0.050" lift while the Reed's cam is not. Note that the Reeds cam talks about 250' running duration but only 222 duration at 0.050". So to compare the cams, subtract 14' from all the Reeds numbers (250-222)/2 to do comparision at 0.050" lift.

intake
- opens at 19' - 14' = 5' BTDC
- closes at 51-14 = 37' ABDC
- duration = 5+180+37=222

exhaust
- opens at 59-14=45
- closes at 11-14=-3
- duration = 45+180-3=222

overlap @ 0.050" lift = 5+-3=2 . . . a full 18' less overlap
Author:  Bren67Cuda904 [ Fri Mar 20, 2009 12:04 pm ]
Post subject: 
I got a hold of Reed Cams and they had a look at the pictures and agree there is a problem with my cam. He looked at another blank on the shelf and that one is good. They are going to regrind it today and send it right off. There also sending a shipping label for the old one. He also gave me the @50 numbers and they are as AL T posted. Looks like they are a stand up company and made it right with no hesitation.
Author:  sandy in BC [ Fri Mar 20, 2009 12:48 pm ]
Post subject: 
Cool!
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