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Old 11-13-2011, 01:56 AM
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cam enlightenment

I'm looking at two different cams that should fulfill my needs or added performance and towing with a dd truck. One is the Isky 262, the other is the crower 266HDP, or part #19213. Am I correct in assuming they are very close in characteristics, but I'd get a bit more performance out of the crower due to added v.lift and duration?

Am I also correct to think that the Isky, with its LSA of 108*, as opposed to the Crower cam LSA of 112, would have a bit more of the loping cam sound at idle? Most likely a bit less vacuum too?
 
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Old 11-13-2011, 02:50 AM
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First, I'm not very familiar with 300 cams, but some things are universal. That isky should have some chop at idle at 108. The Crower is going to idle much better (better vacuum), out rev, and outperform the isky. It looks like the Crower is also going to want a bit more compression. If you have the CR and the choice is between the 2 I'd take the Crower hands down.

10.25:1 CR for the Crower
9.5:1 CR Isky

IMO this cam looks better Clifford Perf

Unless you plan on going drag racing and spinning it up to 6k.
 
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Old 11-13-2011, 01:37 PM
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Originally Posted by Sleepy445FE
First, I'm not very familiar with 300 cams, but some things are universal. That isky should have some chop at idle at 108. The Crower is going to idle much better (better vacuum), out rev, and outperform the isky. It looks like the Crower is also going to want a bit more compression. If you have the CR and the choice is between the 2 I'd take the Crower hands down.

10.25:1 CR for the Crower
9.5:1 CR Isky

IMO this cam looks better Clifford Perf

Unless you plan on going drag racing and spinning it up to 6k.
Thanks. I'm sorry to say that in another forum there is a lot of buzz as to the quality of the Clifford cams, members having them shred bearings in a couple of hundred miles. It seems someone in the factory either forgot to polish the journals, or they turned the cam reverse rotation. Either way, they scare me and I wouldn't touch one. Oh, I forgot to add that while Clifford calls that a 264 duration, at .050" it actually has about the same duration as the Isky 256!

Between the other two cams, Isky and Crower, that's about what I thought. However, I thought Crower mislabeled that cam, some tech geek put in the wrong summary. If you look at the numbers it looks like a pretty mild cam, almost the same as the Comp Cams #260, but Crower talks about it as though it's a full blown drag cam. I just don't by the 10.25 minimum C.r. If that cam was for a 390 or a 351 it wouldn't require such c.r., right?
 
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Old 11-13-2011, 04:20 PM
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I didn't know that about the Clifford cams. I'd steer clear as well if it's got such a bad rep. I actually think that's a benefit of the grind that it retains it's low end like the Isky but is able to breath better up top with a little more duration. Do you know if they have been good on their warranty?

The "performance level 4" seems to fit in line with the rest of the 300 I6 cams listed on that Crower page. Like I said I'm not real familiar with what is and what isn't a large cam for a 300. For a 390 that would be about stock lift with a little more duration, CR would be in the 8.5-9:1 range. VERY mild. But it looks like the I6 cams are all rather small in comparison. I'd call their tech line and see what they say about it.
 
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Old 11-14-2011, 02:47 AM
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Comp Cams makes a 268, 218* @.050", .456 v.lift, with LSA of 110, and they call it a 'moderate Performance' cam. The Crower 266 I mentioned has 210/213* duration @.050", and about the same v.lift, 112 LSA, and they call it hot Street and strip. Something doesn't add up. A drag cam that requires only 80 lbs of seat pressure for installed height @valve? That ain't gunna work...not long, anyway!!

BTW, the 390 has almost the same diameter bore as a 300. OEM v. lift, depending on the model, is .401". Some of the hp models had, of course, more.
 
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Old 11-14-2011, 04:39 PM
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That comp cam looks pretty good too. Depends on what you want. The Crower is going to idle better and have a bit more down low. And the Comp is going to have slightly more lope and come in maybe 200rpm later. It sounds like Comps take on it is more in line with standard thought, "moderate performance".
 
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