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Big lift cams in daily drivers

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Old May 12, 2016 | 11:07 PM
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Default Big lift cams in daily drivers

What's yalls opinion on running high lift cams on a daily? I know on stock heads over about .570 lift isn't doing much good, but my friend has a cam he's gonna give me a screaming deal on that's a 220/224 and like a .617 lift and I don't wanna have to change springs every 10k miles honestly so let's hear some opinions on it.
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Old May 12, 2016 | 11:49 PM
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Your springs are affected worse by the ramp rate of the cam more so than the actual lift of the cam get the cam card and post it up and I'm sure someone can tell you or just call comp or cam motion whichever it's ground by and tell them the specs and they'll tell you exactly what you need to know
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Old May 13, 2016 | 12:14 AM
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Exactly what was said above. While lift does have an effect too it's much more dependent on how aggressive the lobes are.

High lift with stock rockers can be tough on the valve guides regardless of ramp rates...
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Old May 13, 2016 | 12:23 AM
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Thanks fellas I'll try and get the cam card for it
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Old May 13, 2016 | 03:07 AM
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I've got a Comp LSR 265 on the shelf in the garage that I had in the old 5.3. It was in there for about 2 years and I put about 40k on it.

Never had an issue with springs. With any cam over .600 and stock heads, you'll have to use 7.450 PR's else it'll sound like a sewing machine.

I'd measure for the PR, but it wouldn't surprise me if I was right.
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Old May 13, 2016 | 12:11 PM
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Madmann, What springs did you use?
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Old May 13, 2016 | 02:17 PM
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Originally Posted by BlueTexan24
Madmann, What springs did you use?
Lunatic dual .650 I think. They worked well.

The key part is the cams being over .600. When the cams are cut, the base circle of the cam is cut smaller, thus, the need for longer PR's.

If the base circle wasn't cut smaller, the cam would never fit in the hole.
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Old May 13, 2016 | 02:49 PM
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Dropping a valve is not fun.

That cam probably has really aggressive lobes.
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Old May 13, 2016 | 03:42 PM
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I'm thinking it does, it's a custom grind.
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Old May 13, 2016 | 05:37 PM
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Originally Posted by GMCtrk
Dropping a valve is not fun.

That cam probably has really aggressive lobes.

The LSR cams are super aggressive.
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