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Another Cam Q!!!

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Old Jun 24, 2004 | 11:19 PM
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From: Arizona Bay
Default Another Cam Q!!!

I plan on doing a cam swap this summer before I go back to school. I want a bad *** cam, because I only want to do this once. If you had to choose a cam for my lil' 4.8 ecsb what would you choose? I will be getting a tune, 3000stall and possibly spraying some giggle gas too.

I'm not affraid of some lope, so I know I want something with a 112 LSA. Any help would be much appreciated.

I thought I had a cam picked out, but 01 Thunder got me thinkin' again. Thanks man!
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Old Jun 25, 2004 | 12:50 PM
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From: La Porte Tx
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hopefully it all works out, guess I will be a pioneer on this one
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Old Jun 25, 2004 | 12:58 PM
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I think we're all curious as to what Mr. Thunder's setup is going to put out, but until then, I would have to suggest the 212/218 .522/.529 114 Comp Cam. My 4.8 LOVED it, and with the right tuning and converter it would SCREAM.

But, I would love to have tried the high-lift version, or even a TR220. I have a feeling that TR224 is going to rock that little 4.8's world.
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Old Jun 25, 2004 | 02:39 PM
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remember this vanilla

choosing a cam with a high exhaust duration and a lower intake duration such as the comp 212/218 isn't a relatively good thing on our motors, especially with a free flowing exhaust. It leaves the exhaust valves open longer when we you should be leaving the intake valves open longer. It makes since to increase the intake side of the cam to keep the intake/exhaust flows balanced. in other words higher intake duration, not higher exhaust duration is what your looking for.

a reverse split would work better for you especially in a 4.8 extended cab. right now your truck is a 2 time looser with less cubes and being heavy.

edit: about that 2 time loser thing. dont take that the wrong way. meant more like it has 2 things goin against itself. cool?
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Old Jun 25, 2004 | 05:20 PM
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I read a good explaination in the Internal section here on the site.

Intake duration is what raises or lowers the powerband.

Exhaust duration is there to help get exhaust gas out. Even pattern cams idle well, but splits are made to help out vehicles with less than perfect free-flowing exhaust systems.

Lift helps everywhere.
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Old Jun 25, 2004 | 06:15 PM
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So far I have one person for the 212/218 and one person against it. Hmmm.

Sportside 5.3, no offense taken, I get the point. But you metioned keeping the intake and exhaust balanced. So wouldn't a single pattern cam like the TR224 or TR220 do that?

I know my truck is heavy and the 4.8 is small, so I think by spinning it up there with a big fat hairy cam will actually get it going.

I drive this everyday, but I'm not affraid of a lopey idle. But I was also wondering how the vacuum would be for the power brakes? I never hear you guys with big cams talk about that. It's a problem with my Camaro, and its a regular issue on the first gen sites. Do any of you guys have a hard pedal?
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Old Jun 25, 2004 | 06:23 PM
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From: La Porte Tx
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Who needs Brakes, your trying to go faster right? Brakes will only slow you down!!!!
lol

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Old Jun 25, 2004 | 06:58 PM
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Originally Posted by vanillagorilla
So far I have one person for the 212/218 and one person against it. Hmmm.

Sportside 5.3, no offense taken, I get the point. But you metioned keeping the intake and exhaust balanced. So wouldn't a single pattern cam like the TR224 or TR220 do that?
If all was balanced, yes, single patterns like the TR's you mentioned would be perfect, buuut. our intake and exhaust are not balanced. The split of Comps 212/218 is to aid a restrictive exhaust. (Leaving the exhaust valve open longer)

The LS1 motors have a very efficient exhaust. For example, a magazine i read "Corvette Fever" did a bolt on test. After changing out the whole exhaust (new:cats, headers, mufflers, 3in tubing) they gained 40rwhp and 30rwtq. This was on a stock M6 vette.

The point im trying to make is, with an efficient exhaust, you should keep away from high exhaust durations, matched with a lower intake.
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