Cam Lift on Solid Cams

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dodge freak said:
Was looking at the MP 4120653AB Mechanical flat tappet with 0.528 int./0.528 exh. lift.

The lash is .028 and .032. So my question is, what is the lift at the valve, the full .528 or is that with no lash--which never happens even in a hot running motor.
Click to expand...

That is actual cam lift x the rocker arm ratio. Or .528 minus valve clearance.
 
SGBARRACUDA said:
That is actual cam lift x the rocker arm ratio. Or .528 minus valve clearance.
Click to expand...

In theory this is right. But considering the offset pushrod angle on SB Mopars you loose some more. With perfect geometry you still loose .015~.020"

With that said you can expect approx. .480~.485 lift with perfect geometry.
 
Sounds like it could be a neat little cam. Too bad you have the buy the lifters--without the tiny hole to help lube the lobes.

I have heard thou that Mopar cams can be way off. Why am I'm thinking some place in China are turning these cams out
 
You mean those lifters with the tiny laser drilled hole? There a new idea on the market, so "Needing" them is a option.

I have a cam be way off from many manufactures.

FWIW, I have a Comp solid lifter cam in my 360 now with .022 lash. The cams lifts is .525.
525 (lift) - 022 (Lash) = 503 actual (In theroy it should be by the numbers at least)
Measured .510 at the valve. Also, rocker arm geo. isn't perfect nor is the contact patch and travel perfect. The Edel. heads still need some work in the valve area and there stem height.
 
If this is a small block, you lose around .019" at the valve due to pushrod angle, more with stock rockers. So depending on what you're doing that might be important to you. The .528 is a great cam but not very large or very large-behaving.
 
Dodge Freak,
That '653 .528 solid is a great little cam..you WILL like it. A good choice.
What they are saying about the poor geometry in small Block Mopars is very true. We can't really use the std. formula to find 'true' lift. It won't work with the small Mopars. We lose .010 lift on the rocker end of the pushrod because the lifter and pushrod are not in plane with each other. I use a VERY accurate and simple formula to calculate the 'as installed' lift with Hyd. or solid (mechanical) camshafts. using the .528 solid as an example .. 528 divided by the stock design ratio of 1.5 , gives us a lobe lift of .352 subtracting the .010 lost motion gives us a true lobe lift of .342 at the rocker end of the pushrod. Multiplying this with the rocker ratio you will be using in this case is 1.5 , gives a lift of .513 subtracting the lash of .026 (what I use) gives a true as installed lift with lash of .487 . If you are using a Hyd. grind you will not have lash to introduce into this formula. My XE 275 HL comp gives me .544 at the valve as installed with 1.6 rockers. Hope this helps. Nothing wrong with getting it right. Paying attention to detail is always a good thing. JMHO.
Terry
 
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