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  1. #1

    Default Lumps in your cam anybody?

    No not lumps in your gravy...Lumps in your cam I said.



    Alright, I haven't researched it much but can I get an aftermarket cam for the 5700 Vortec L31? I'm having a hell of a time finding one.



    Jamie

    2007 Ford E250(Work van) (Ya, Ya, shut up!)
    1996 GMC Sierra SLE 1500 5.7L/4L60E

  2. #2

  3. #3

    Default

    I forgot about Summit, Thanks. There's 6 different kinds. I guess I'll have to see how much lump I can get away with. I don't want idle troubles or vacuum troubles.

    You da man



    Jamie

    2007 Ford E250(Work van) (Ya, Ya, shut up!)
    1996 GMC Sierra SLE 1500 5.7L/4L60E

  4. #4
    Sr. Apprentice justcuz's Avatar
    Join Date
    Aug 2007
    Location
    Alta Loma, Ca.
    Posts
    55

    Default

    The wider the lobe separation angle the less lope you have from overlap. The less lope the more vacuum. Stay in the area of a size or two up from stock and you should be fine. I run a 415/430 cam in my flat tappet engines and it has good bottom end and power throughout. Stock for a 350 flat tappet was a 390/410 cam and a 305 HO and Corvette 350 cam was a 403/415. So as you see I am about two sizes up from a stock cam. The next size up would be a 420/442 which is a little smaller than a L79 327 of 447/447 and a 350/350 at 450/460. The thing to remember is today most engines do not run over 4000 rpm very often, most engines are running a little over 2000 rpm in overdrive at about 70 anyhow so you need to keep the powerband of the cam down low.

  5. #5

    Default

    Thanks Justcuz Very good advice. I haven't messed with a cam in a long time. It appears my auto skills need a little tune up (Thats why I went back to something I could tinker with)



    Jamie

    2007 Ford E250(Work van) (Ya, Ya, shut up!)
    1996 GMC Sierra SLE 1500 5.7L/4L60E

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