Choosing a flat tappet cam for vortec 350

Discussion in 'Engine Topic' started by RockinZ, Nov 29, 2008.

Narrowed to 2 cams, help me choose!

Poll closed Jan 5, 2009.
  1. Voodoo 268 H

    7 vote(s)
    58.3%
  2. Comp XE 268 H

    5 vote(s)
    41.7%
  1. RockinZ

    RockinZ Veteran Member Gold Member

    1,468
    0
    Oct 18, 2008
    Montreal, QC, Canada
    Choosing a Hydraulic flat tappet cam for vortec 350

    Hi Everyone, I'm pretty new to this forum and being a chevy owner (mopars 25 years ago)
    I am building my first engine.
    it's meant for fun on the street and maybe a drag race here and there.

    I have a '84 350 .020 over.
    '96 Vortec heads 2.02 / 1.60 valves & ported
    Flat top pistons with valve relief .025 in the hole
    9.7 to 1 compression
    Edelbrock performer 2116 intake
    Qjet
    stock converter (I think)
    TH350 & 2.41:screwup: gear BUT planning 700r4 / 3.73 grear

    I had decided on a Voodoo 262 (60102), but then read a story on this forum about a lobe on this cam going flat after 3000 miles. Some say the aggressive lobe angles on these advanced cams cause a durability problem. I realize it's only one story, and I still want to try the Voodoo cam, but has anyone got a similar set-up? Any advice?

    Thanks,
    Kyle
     
    Last edited: Dec 16, 2008
  2. Spot_remover

    Spot_remover Veteran Member Gold Member

    861
    0
    Aug 24, 2008
    Murrayville.Ga
    I'm gonna run a small Thumpr in my 355 vortec. Should have it together in a couple of weeks i'll let you know how it does.
     
  3. RockinZ

    RockinZ Veteran Member Gold Member

    1,468
    0
    Oct 18, 2008
    Montreal, QC, Canada
    I forgot to mention the vortecs have screw in studs and guideplates
     
  4. andrewsreed

    andrewsreed Veteran Member

    252
    0
    Aug 20, 2008
    Federal Way, WA
    get a roller cam... my vortect motor has a roller cam and it makes awesome power and will rev to the sky...
     
  5. hardline_42

    hardline_42 Veteran Member Lifetime Gold Member

    How ported are the Vortecs? If the intake/exhaust flow ratio has changed from stock it may affect your cam choice. Otherwise, I would suggest the Comp Cams XE 268 if it's more street than strip.
     
  6. RockinZ

    RockinZ Veteran Member Gold Member

    1,468
    0
    Oct 18, 2008
    Montreal, QC, Canada
    BLOCK: I made a mistake in the specs, my block is an '84. Not set-up for roller, and I don't want to get into modding the block.

    PORTING: I don't know enough to tell you, I think they have just been smoothed out a little and the valves are bigger. My buddy who is an ex mechanic said that the port job was nice. That's all I know. There are pics in my gallery, but there a little low rez, I can post better if that helps.

    CAM: I was staying away from the XE 268 because of the 110 lsa. I have been advised to look for 112 or higher to create better vacuum and torque on the bottom end. But I keep seeing it getting recommended everywhere. There's also the Crane PowerMax 272-2 pn114142, It has been recommended as well.
     
    Last edited: Nov 29, 2008
  7. docwilcar

    docwilcar Veteran Member

    172
    0
    Jul 19, 2008
    WABASHA, MN
    Comp 268HE, Energizer 272, both on 110 lsa, will give you plenty of vacuum(15-16"). If you want a rump rump idle that is still very streetable, try the Crane Energizer 100172 218-218 .454 lift on a 106 lsa. 14" of vacuum at 1000 and will sound like you have a thumper cam in it. May need a mild stall with a T350 or 700r4. My buddy just put one in his 8.5 cr crate motor and the cam is very strong in the low and midrange and pulls all the way to 5600 no problem with stock springs.
     
  8. Incenter12

    Incenter12 Veteran Member Lifetime Gold Member

    482
    0
    Jan 19, 2007
    Meridian, MS
    I've got 906 vortecs on my 350 with dished pistons and I threw in the Comp 268H with the performer intake. I need a little higher stall for my TH350 and I'm thinking of bumping the 3.08 out back up to 3.73.

    Here's a video from break-in,

    http://www.youtube.com/watch?v=RtJ8Fw1_y9M
     
  9. GoldenOne7710

    GoldenOne7710 Veteran Member Lifetime Gold Member

    3,671
    7
    Jun 23, 2004
    Athens, GA
    Either the Crane, Comp, or Lunati cam in that same class will all perform close to the same. They will all have impressive that low-end grunt you desire. You may consider swapping your converter to a hair higher one.....maybe in the 2000-2200ish range. As for gears, I'd go with the 3.73 ONLY if you're definitely going with the 700R4. If you keep the TH350, a 3.42 would feel better (all around) for your package.

    I may be wrong, but 9.2cr seems a little low for Vortecs and flat-tops....even WITH the valve reliefs. Are you sure that's right? Seems like it'd be closer to 9.5-9.7...
     
  10. RockinZ

    RockinZ Veteran Member Gold Member

    1,468
    0
    Oct 18, 2008
    Montreal, QC, Canada
    You're right, the CR I got is 9.7, so much for regular octane!:eek:
     

Share This Page