Do GM crate 350's have soft cams ?

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roundhouse

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Cam?? Driver side???
Usually the cylinder closest to the firewall on the drivers side has a wiped cam lobe

Easy way to tell is drive it and hold the trans in second gear and when the RPM gets pretty high you can hear it start making a popping sound back thru the intake

Or you can remove the valve covers and usually see the rearmost rocker arms on the drivers side not moving much at all
 

73c20jim

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Thanks for the clarification. I was really confused there.
 

Old77

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even with the clarification it still makes me giggle :shrug: I kinda had an idea what he meant but still found it humorous.
 

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New cams also have to be broken in

You have to use special oil and the first time you fire it Up you rev it to 3000 and keep it at 3000 for like 20 minutes to harden the lobes


And just about every old small block Chevy I’ve ever seen has a flat lobe on the cam

Usually the one on the drivers side at the back
Break-in is more like 1800-2200 RPM for 20-30 minutes. Varying the RPM is important to change which parts of the cam get splashed.

Interesting that most SBCs you've seen have had a flat lobe. I've been building and working on them for over 50 years, and have yet to see even ONE! That said, I haven't used any of the latest ultra high intensity cams. And I have always used the proper valve springs installed at the proper height. (Well, maybe not when I was a kid. :))

By drivers side back, I assume you mean cylinder nos 5 or 7?
 

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Lost an intake lobe on cyl #5 in my 350. Wasn't completely wiped, but it sure was done. That was on an Isky replacement after ~50-60k on it over 30+ years.
 

73c20jim

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In my youth, I put used "Isky Anti-Pumpup Hydrolic" lifters on my existing original cam in my 1963 Chevrolet 340HP 409 CID motor, and wiped several lobes clean.

Then I got a used 340HP 409CID cam and put my original lifters back on and it lasted several years until I sold it. (sob. sob.)

Go figure.
 

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