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Base Circles Different on Lunati Cam

padam

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I am installing a Lunati hydraulic Flat tappet cam.
Part number 10230906.
I checked the lobes,
The exhaust base circles are 1.222.
The intake base circles are 1.257, for a difference of .035".
That seems like a lot to me.
The numbers over the lobe match up to the cam card.
I am using Rhoads lifters and non-adjustable rockers.
Is this going to be ok?
 
I guess this may be correct, since the exhaust lift is .534,
Intake lift is .509.
 
Its common to run a different lobe profile on the intake and exhaust. Not sure what your question is relating to the base circle?
The voodoo 704 like you have is about all I would run as far as lift with stamped rockers. Stamped steel rockers typically run 1.45-1.47 ratio resulting in less lift then advertised. It's hard to say as they can vary. May not even be .5 on the intake at the valve.
Stamped steel eventually can poke a hole through the rocker. Typically just starts 2 miss and you have to replace a rocker and pushrod and go again. Is it ideal?..no. but guys on a budget do it all the time.

We have the same cam in a 383 with stamped steel in our dart. It was a budget build and I am not worried about it, but I don't plan on driving the car on any 1000 mile road trips either. Maybe 250:)...to the drag strip and back.Lol

20210220_171023.jpg
 
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Lift is increased by reducing the base circle........ not by making the nose taller.

More lift = smaller base circle.
 
Lift is increased by reducing the base circle........ not by making the nose taller.

More lift = smaller base circle.
You can see the difference on the base circle on these two roller cams we have. A old street roller .530 lift on the right...superstock roller .730 lift on the left
20210515_113220.jpg
 
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I think I get it now. I was comparing it to my old cam that had same intake and exhaust lift.
I just have to balance out the pre load and I think it will be ok.
 
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