INTERNAL ENGINE MODIFICATIONS Valvetrain |Heads | Strokers | Design | Assembly

4.8 Valvetrain

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Old Dec 29, 2007 | 12:00 PM
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Default 4.8 Valvetrain

The 4.8 Lifters are flat tappet hydraulic right? cuz I went to this weak *** "performance shop" here in mesa and the guy gave me a weird look when I told him they werent rollers ractory. So Im just makin sure. Another thing, what kinda springs should I look in to with my cam that has .551 lift.. like what should I look for in the springs? (the lb rate it can handle or the height stuff like that..) Thanks guys
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Old Dec 29, 2007 | 01:56 PM
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he was infact correct, your 4.8 has a factory hydraulic roller cam, as for springs, ive yet to have issues with the comp 918's
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Old Dec 29, 2007 | 03:36 PM
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Ditto on they are factory hyd rollers.
John
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Old Dec 29, 2007 | 04:59 PM
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hmm, well aint that some ****.. now I look like an ***..
all well huh.. well thanks for the advice guys Ill give everyone an update as soon as I get all that in the little monster
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Old Dec 29, 2007 | 05:16 PM
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I read somewhere the other day that all OEM's now use roller cams. This allows the engine oil mfr's to phase out a zinc additive which damages the cats. I'll see if I can find the article. BTW, I can personally verify that the 4.8 has roller cams because I rebuilt one a year ago.
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Old Dec 29, 2007 | 06:08 PM
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All ls Motors are hyd. roller
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Old Dec 29, 2007 | 07:20 PM
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alright well thanks guys but about the springs.. any one have a part number for the 918s? any suggestions or anything for maybe some on the cheaper side springs or some other springs to look in to? As of right now my valvetrain is gonna be Lunati 221/221 .551 -114LSA cam with GM perf parts roller lifters, trickflow 7.4in rods, a GM factory timing chain(new), and just need springs and I think I will be set cuz I can get the gaskets and chain from my dad's work for nothing. So anything suggestions for cheap and reliable choices would be great. Thanks guys
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Old Dec 29, 2007 | 07:23 PM
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o and either a B&M Torkmaster 2500(or 2800 dont remember) Converter or a 2100 Converter from Redstar Performance... Thanks for any feedback
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Old Dec 29, 2007 | 07:24 PM
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for the record, gm hasn't had flat tappets in anything since the '95 tbi trucks. cars already went roller in '87. there might be some exceptions to that, but am pretty sure. on a personal note, the straight pipe on a 4.8l didnt make you look like an *** first. lol. just picking on ya, man.

Last edited by acethedragon; Dec 29, 2007 at 07:33 PM.
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Old Dec 29, 2007 | 07:25 PM
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you dont need new lifters, but if you really want to get some i hear the LS7 lifters are good ones to get

also look into getting the LS2 timing chain, its a little beefier
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