Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Interesting Stuff

Discussion in 'The Garage' started by Hardcore, Aug 13, 2003.

  1. Hardcore

    Hardcore 1/2 ton status

    Joined:
    Apr 25, 2003
    Posts:
    458
    Likes Received:
    0
    Location:
    New Orleans, LA
    May be old news to some of you guys but I just read this on another board

    "Comp Cams just released 4-7 swap firing order cams for smallblock chevy. Claims marked horsepower increases. Same firing order in Mopars. The two cylinders are opposites in the firing order so they are swapping the power and intake strokes on the two cylinders. Just install the cam as normal, and swap the plug wires. With 18436572 you have 2 cylinders on the same bank firing in sequence twice in each revolution. The new firing order 18736542 fires from bank to bank through the full revolution, with only one same bank sequence."

    Wonder the power gains it really gives? /forums/images/graemlins/thinking.gif
     
  2. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

    Joined:
    Jul 23, 2000
    Posts:
    36,169
    Likes Received:
    1,368
    Location:
    E-town baby!
    You'd think all it would do is allow for more balance...I can't really see a power gain unless I'm missing something obvious. (wouldn't be the first or last time/forums/images/graemlins/crazy.gif)

    Can you imagine the confusion it would cause if you sold a car with one of those cams? If the next owner didn't know about the Mopar firing order they could be scratching their head for a while if they swapped wires or something.

    Rene
     
  3. k20

    k20 3/4 ton status

    Joined:
    Sep 9, 2001
    Posts:
    5,068
    Likes Received:
    0
    Location:
    Mineral Springs, NC
    thats what the drag cars run.......in a car magazine a couple months ago they were talkin about em, and the magazine said it was 'significant power gains' so i guess that means what? 10?
     
  4. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    I bet it helps with scavaging effect in the exhaust. Isn't that the firing order on the Vortec?
     
  5. Beast388

    Beast388 1/2 ton status

    Joined:
    Nov 6, 2001
    Posts:
    3,039
    Likes Received:
    0
    Location:
    Clinton, IA USA
    Hmmm.....very interesting! Too bad they are only for oval track and drag racing apps so far. Here is the info from Comp Cam's site:

    "COMP Cams®, the leader in cam technology, is proud to introduce 4 & 7 swap firing order cams for Chevrolet solid roller and flat tappet applications. These cams provide an exceptionally smooth torque curve and a significant decrease in crankshaft deflection. COMP Cams® 4 & 7 swap cams require no additional engine modifications and are available in Chevrolet Small Block and Big Block applications. The 4 & 7 swap firing order cams have been dyno and track tested in a variety of applications. Customers have reported an increase in horsepower over traditional firing order cams.

    For more information, contact us at 1-800-999-0853 or http://www.compcams.com. "

    /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif
     
  6. yunit

    yunit 1/2 ton status

    Joined:
    Feb 24, 2000
    Posts:
    3,068
    Likes Received:
    0
    Location:
    Oakland, NJ
    Too bad...those 2 cylinders are dead in my truck, guess I am not going to be able to perform this mod. /forums/images/graemlins/frown.gif

    Just kidding. /forums/images/graemlins/rotfl.gif
     
  7. jarheadk5

    jarheadk5 1/2 ton status

    Joined:
    Mar 6, 2000
    Posts:
    4,389
    Likes Received:
    0
    Location:
    PA
    I read that recently too. Apparently the high-dollar racing engine builders (for NASCAR, NHRA, CART, USAC, etc.) have been using this for some time. The article I read claimed that, all other factors the same, the 4-7 swap is good for 10-15 HP. I didn't see dyno charts, but I was only skimming through the magazine. I think I saw it in Super Chevy magazine as a SBC Tech Tip, but I'm not sure.
     

Share This Page