Re: Questions for the camshaft Gods
[Re: Moparteacher]
#2809007
08/14/20 08:13 PM
08/14/20 08:13 PM
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Joined: Aug 2003
Posts: 43,163 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,163
Bend,OR USA
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I ran a similar solid roller in my old pump gas duster, it was 260@.050 int. lobe with .420 lobe lift and 266@.050 on the x. lobe with .409 L.L. ground on 108LSA installed at 106 and later at 107 ILC. That rascal ran really good in that motor with both 9.25 to 1 compression ratio with a set of big valve 906 heads and a low deck Eddy six pack intake with a set of 1970 440 six pack carbs. at 511 C.I. and ended up later with 1.0.78 to 1 comp. ratio with a set of Indy SR M.W. ports and a 400-3 intake with a 1050 CFM Holley Dominator carb with 517 C.I.
Last edited by Cab_Burge; 08/14/20 09:56 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Questions for the camshaft Gods
[Re: Moparteacher]
#2809036
08/14/20 09:06 PM
08/14/20 09:06 PM
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Joined: Mar 2011
Posts: 3,075 Michigan
A727Tflite
master
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master
Joined: Mar 2011
Posts: 3,075
Michigan
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Bonjour! I have two flat tappet camshafts. Different manufacturers, one solid, the other hydraulic. different applications but same engine series (BBM). I have found both camshafts have a a base circle that drops .001" approximately 50 crankshaft degrees (25 camshaft degrees) prior to the ramp.
Q. #1. Is this drop prior to the ramp what is referred as the heel? I think the answer is yes, but seeking a second opinion is always a good thing. Q. #2. What's it's purpose? To put oil under lifter base? Q. #3. When mapping a camshaft should the dial indicator be zeroed at the base .000, or the drop (heel) prior to the ramp? I assume the base and not the heel, for valve adjustment EOIC puts the lifter at the base and not the heel. Q. #4. What is the typical length of the take-up ramp on a solid (mechanical) 7*, 8*, 15* of camshaft degrees??? And, again is this measured from movement zeroed on the heel or zeroed on the longer base?
OK, Thanks. 1). The drop is called a clearance ramp. The heel and the base circle are one in the same. 2) To slow down the lifter on the closing side to prevent valve bounce. On the intake side it is to promote stabile valve opening. 3) At true base circle, but I guess it depends on what you are trying to map. Lift, duration, what? 4) I would imagine that depends on the design (hydraulic, solid,roller) intended use, spring pressure,,etc.
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Re: Questions for the camshaft Gods
[Re: lockjaw-express]
#2809884
08/17/20 07:19 PM
08/17/20 07:19 PM
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Joined: Oct 2006
Posts: 1,264 New York, USA
Chargerfan68
pro stock
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pro stock
Joined: Oct 2006
Posts: 1,264
New York, USA
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Call Mr. Porter at Porter Racing Heads...he knows everything there is when it comes to camshafts! Buy one from him, and you will be very happy! I did, am I ever impressed!
I agree 100% with the above. Never dissappointed and expectations have always been surpassed.
1.50 60Ft. , 10.75@ 127MPH Hauling 3900 LBS.
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Re: Questions for the camshaft Gods
[Re: Brewzer67]
#2809944
08/17/20 09:12 PM
08/17/20 09:12 PM
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Joined: Aug 2003
Posts: 43,163 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,163
Bend,OR USA
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That cam was used in that block with two different stroke cranks, 4.25 and 4.300, and five different sets of heads, ported big valve 906,eddy RPM CNC ported by MCH, a set of ported 440-1 and I ended up using a set of Indy SR M.W. heads. The 440-1 heads made 775 HP at 7000 RPM on Oregon pump swill and the SR heads made 725 HP at 7000 RPM on the same dyno two weeks later, both sets of those heads had 76.0 CC chambers so the compression ratio stayed the same. The fastest and quickest my 3450 Lb. Duster ran with that last combination on Oregon 91 octane pump swill was 9.996 at 134.7 MPH at Woodburn, OR in late July IHTHs
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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