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I HAVE A BENCH GRINDER FROM HARBOR FREIGHT. IT HAS A 6” WHEEL. I THINK IT’S TWO YEARS OLD. OR MAYBE IT WAS FROM LOWES. I FORGOT...
 

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I haven't dynoed with Mike's cam but a pump gas 400 small block/th350 making enough power to wheel spin all the way and drift sideways through the traps doing 8.1 second 1/8 in a 3600lb car raised alot of eyebrows here. Pro Touring car on low profile street tires. . Would be faster with drag radials and if my damn foot wasnt so heavy.

Berko or CNC I know who I'll ask to grind my next cam thats for sure.
 

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CNC doesn't mean better - it's only faster.
Many times with cnc ground cams one can see the stepper resolution on the surface.
Yes, I have also noticed that on CNC ground cam lobes. You can see diamond like facets on the faces of the lobes, but I cannot actually feel the steps with my finger nail.
 

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Yes, I have also noticed that on CNC ground cam lobes. You can see diamond like facets on the faces of the lobes, but I cannot actually feel the steps with my finger nail.
Here's a cam we just pulled off of one of our Berco's. This entire cam was made inhouse(except heat treating). The core is S7 tool steel, and CNC machined. The dist gear is made out of 8620. After the cam core is thru-hardened to 60hrc, the end of the core is turned down between centers, and the gear is pressed and pinned in place, so the gear is concentric to the centerline of the cam. The rear journal is then pressed on, and all journals are turned down to size.
The cam core is then finish ground on one of the Berco cam grinders.
65586
65587
 

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That came out nice!! Question - Do the lobes have an inverse on the opening side and more conventional closing?
That's for a turbo engine, and the profiles have the same inverse on both sides. I do have a lot of asymmetrical profiles where the opening side has a much more aggressive inverse, then the closing side, but I usually only use those as intakes, on normally aspirated engines. Most supercharged engines don't respond as well, to the faster opening, and slower closing profiles.
 

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Do IR lobes require a different degreeing process than conventional lobes?
 

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Do IR lobes require a different degreeing process than conventional lobes?
No, but asymmetrical lobes do. Our Inverse Radius profiles can be symmetrical or asymmetrical.
With the asymmetrical profiles, you have to degree them off the .050" opening and closing numbers on the cam card.
our asymmetrical profiles have a faster/shorter opening side, then the closing side, and max lift isn't in the center of the cam profile
 

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OK. Are there any lobe designs that 0.050" tappet lift is NOT the way to degree them?
 

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Not that I know of. That's the method I recommend to my customers.
You still using that old bench grinder to grind your cams on?? If you have up graded to a real cam grinder please post some pics please.
 

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Here's a cam we just pulled off of one of our Berco's. This entire cam was made inhouse(except heat treating). The core is S7 tool steel, and CNC machined. The dist gear is made out of 8620. After the cam core is thru-hardened to 60hrc, the end of the core is turned down between centers, and the gear is pressed and pinned in place, so the gear is concentric to the centerline of the cam. The rear journal is then pressed on, and all journals are turned down to size.
The cam core is then finish ground on one of the Berco cam grinders. View attachment 65586 View attachment 65587
Mike, are you making your own cores now? If so, that is great news. It should really help with throughput. The wait for cores can be long.
 

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Mike, are you making your own cores now? If so, that is great news. It should really help with throughput. The wait for cores can be long.
We're making our own Tool Steel cores, and also buying cores from the 3 major core suppliers.
We started making cores, because it's been so hard to get them from the major core manufacturers. They no longer stock anything, and won't make a run of a part#, until they have a bunch of them sold.
We looked at making 8620 steel cores, but we couldn't get the price close to what the mass-produced 8620 cores go for, so I figured if we can make a better product, we can justify the higher price. We figured out that we can make short runs(20) of a tool steel part#, and have a price point that's about half the cost of what other's tool steel cores.
We charge an additional $225 to upgrade from an 8620 core, to our Tool Steel core.
We use S7 tool steel, and it's thru-hardened to 60hrc, so you never have to worry about grinding through the heat treat. It's also has much higher yield and torsion strengths then 8620, so it can handle higher spring loads, with less cam flex.
We presently have part#'s for SB Chevy in 50mm, and 55mm journals, BB Chevy in Stock, 50mm, and 55mm journals.
Chevy LS1 in 55mm and 60mm journals.

We're starting on Ford cores now.
 
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