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Overlap and vacuum accessory performance...

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Old 06-23-2004, 10:38 AM
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Default Overlap and vacuum accessory performance...

Has anyone ever run into any vacuum problem running cams with moderate overlap, or 112 LSA / lopey cams in general? (I don't have any specific number to mention.)

I'm mainly concerned with brake performance with these 1500 series trucks.

I tow/haul a good amount, so I'd like to keep a lot of power going to the brakes.
Old 06-23-2004, 11:01 AM
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Yes. I have problems braking, have to pump them a couple times depending on how fast I was going. Everything else works just fine.
Old 06-23-2004, 11:09 AM
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No problems with my 113 LSA.
Old 06-23-2004, 12:34 PM
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Cool, thanks guys.

OBX, what duration are you running?
Old 06-23-2004, 01:46 PM
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Originally Posted by marc_w
Cool, thanks guys.

OBX, what duration are you running?

208/216@.05

A bit small, but the price was right.
Old 06-23-2004, 02:18 PM
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I ran a 220/220 cam on a 110LSA... idle vac was VERY poor and braking ability was bad also. I'd think that more street cams on a 112LSA would be okay for these trucks.
Old 06-23-2004, 02:21 PM
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OBX: I'm on a small-cam-kick right now. I'm looking at one very close to that, on a 112.
How do you like yours in general?

I hear those Crane's with the .530 lift have a decent tickle at idle... I think that's what you have, right?

That thing must have sounded pretty mean, X... who ground it?
Old 06-23-2004, 11:07 PM
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****, I can't recall who ground it. This was like back in the late 90s. It was in a 306 (.030 over 302). It pulled great all over...it was backed by a PI Stallion converter.
Old 06-23-2004, 11:20 PM
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I hear ya.

The last cam I ran was a Lunati, in my 350 Olds, back in like 97-98. I can't remember the specs for the life of me!

I just know it only loped when cold, and I lost a noticeable amount of lowend. I was so dissapointed.
Old 06-23-2004, 11:26 PM
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Actually, I do remember it was on a 115LSA. Now I'm all pro-overlap.

I think the durations were low. Lift was of course low, like most flat-tapped SBC cams.


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