Need help with cam selection

Big Block A body Tech

  1. dustya_383

    dustya_383 Well-Known Member

    Messages:
    1,156
    Likes Received:
    33
    Joined:
    Oct 7, 2009
    Location:
    san Jose Ca
    Local Time:
    5:58 PM
    Hello everyone, been a member here for a while but have not been logged in in over 2-3 years. im currently putting my 440 together and the time has come to pick a cam shaft.this will be a street car that I will track often. im not worried about streetability too much. looking for a solid flat tappet suggestion.

    440 +.030 4 speed
    -forged crank, ly rods, L2295 speed pro pistons which have had dome machined off to be a flat top im roughly 30-40 in the hole
    -eddy rpms ported 2.19in 1.8ex
    -crane gold 1.5 roller rockers
    440 victor intake

    im thinking about the .557 purple shaft ,or a custom ground ultra dyne/ bullet. I also have access to a clay smith 304 525lift solid cam, this is my first big block build
    some sound clips of set ups would be awesome, thanks this is going in a 67 fastback barracuda for the record
    - Stephon
     
    Last edited: Mar 19, 2020
  2. DrCharles

    DrCharles Well-Known Member

    Messages:
    654
    Likes Received:
    397
    Joined:
    Jun 7, 2012
    Location:
    West Plains, Mo.
    Local Time:
    7:58 PM
    Some more information about your project would help...
    What's the compression ratio with those pistons and heads?
    What rear gears are you going to run?
    If automatic, what stall speed can you live with on the street?
    Weight of car + driver?
     
  3. dustya_383

    dustya_383 Well-Known Member

    Messages:
    1,156
    Likes Received:
    33
    Joined:
    Oct 7, 2009
    Location:
    san Jose Ca
    Local Time:
    5:58 PM
    I’m not sure of the weight of the car it’s still on jack stands with no interior or drive train .

    compression will be around 10.3:1 based upon compression calculator .
    It’s a 4 speed and will be running most likely a 4:10 gear
     
  4. DrCharles

    DrCharles Well-Known Member

    Messages:
    654
    Likes Received:
    397
    Joined:
    Jun 7, 2012
    Location:
    West Plains, Mo.
    Local Time:
    7:58 PM
    I suspect you're going to get a lot of opinions here :rolleyes: If you don't already have AndyF's book, you should.

    The purple shafts are definitely old-school but easier on valvetrain parts than a modern grind that uses all of the .904 lifter capability. Are you sure you don't want to go with a roller?

    How ported are your heads - what do they flow?

    That Victor manifold will make plenty of power but on the street it may not be the best choice either. The top-end hp you give up by using an RPM Air-Gap will be more than made up by the midrange torque on the street.
     
  5. dustya_383

    dustya_383 Well-Known Member

    Messages:
    1,156
    Likes Received:
    33
    Joined:
    Oct 7, 2009
    Location:
    san Jose Ca
    Local Time:
    5:58 PM
    These heads were actually ran with a roller cam ,I just know rollers are pretty expensive, any input on the clay smith cam mentioned above ?a friend of mine has brand new in box with lifters and was considering it think it’s a custom grind .

    image.jpg
     
  6. oldkimmer

    oldkimmer FABO Gold Member FABO Gold Member

    Messages:
    14,112
    Likes Received:
    3492
    Joined:
    Nov 11, 2006
    Location:
    Kindersley, Saskatchewan,
    Local Time:
    7:58 PM
    With that head flow I would be looking for something with .575 lift. Kim
     
  7. rumblefish360

    rumblefish360 So close, yet so far away FABO Gold Member

    Messages:
    37,497
    Likes Received:
    9183
    Joined:
    Jun 21, 2005
    Location:
    New York, on a Island
    Local Time:
    8:58 PM
    Hey Stephon! I remember your screen name. It has been awhile. Welcome back.

    I’d like some specs for the Clay Smith cam @.050. It is a low lift @ .525.

    Here is what I would do. Food for thought for you.

    Mill the cylinder head slightly for a 1/2 - 1 point in compression.
    Sell/Trade the rockers for a 1.6 ratio
    Use the MP Purple 296/.557

    New lift is .594 without lash adjustment. MP calls for a .028/.032. You could run tighter. But it will at least get that valve up into the heads higher flowing area.
    Talk with Mike (Member B3) about valve train geometry)
    I’d run the RPM. With a 1 inch open spaced if room allows. You’ll give up nothing to very very little on the top end but gain huge on the low and mid range.

    The 296/.557 is the largest cam I would use a dual plane on. Not a single plane. Not on a full weight or semi lightened car. Your ‘67 is not a light weight. (I have a ‘67 small block) The next size up Purple cam (at a min. size cam) I’d use a single plane with in a lightened car.
     
  8. dustya_383

    dustya_383 Well-Known Member

    Messages:
    1,156
    Likes Received:
    33
    Joined:
    Oct 7, 2009
    Location:
    san Jose Ca
    Local Time:
    5:58 PM
    thank you for the info I’ll consider it for sure , here are the specs on the clay smith cam.

    7ED273CC-D57D-4581-A93E-9E007F6C9313.png
     
  9. rumblefish360

    rumblefish360 So close, yet so far away FABO Gold Member

    Messages:
    37,497
    Likes Received:
    9183
    Joined:
    Jun 21, 2005
    Location:
    New York, on a Island
    Local Time:
    8:58 PM
    Oh heck if you can get 1.75 rockers, I’d run it!
    A slow lift lobe fixed via a rocker ratio change....
    Oh yea!
     
  10. PRH

    PRH Well-Known Member

    Messages:
    1,634
    Likes Received:
    2407
    Joined:
    Dec 14, 2018
    Location:
    So. Burlington, Vt
    Local Time:
    8:58 PM
    That Smith cam will work fine.

    If the heads were previously run with a solid roller, the springs are likely way too stiff for a flat tappet cam.

    Have them tested to make sure the parts are compatible.
     
  11. dustya_383

    dustya_383 Well-Known Member

    Messages:
    1,156
    Likes Received:
    33
    Joined:
    Oct 7, 2009
    Location:
    san Jose Ca
    Local Time:
    5:58 PM
    yes I was going to remove these springs and get the proper springs, thought about running the same cam as the guy was selling it also but figured I would weigh out my options and with something a bit more mild than he had he was running a .630 lift cam
     
  12. MerlinsMopar

    MerlinsMopar FABO Gold Member FABO Gold Member

    Messages:
    171
    Likes Received:
    189
    Joined:
    Jun 6, 2014
    Location:
    Middletown Pa
    Local Time:
    8:58 PM
    Racer Brown will build you a custom shaft according to your build. You should atleast call and talk eith them. He usually dont answer the phone till after 3pm est but a whole lot of knowledge there and you definitely wont be disappointed. They also have killer lifter pkgs to go with the cams.
     
    • Like Like x 1
    • Agree Agree x 1
    • Bighead440

      Bighead440 Well-Known Member

      Messages:
      244
      Likes Received:
      161
      Joined:
      Jun 18, 2017
      Location:
      Milledgeville, Georgia
      Local Time:
      8:58 PM
      The possibilities are endless, as you can imagine. This cam worked well for a 383 TRW dome poston setup I ran a while back. Trouble free and very strong. See if you can find a 1.6 Crane set and use 8 of them on the intake valves and your 8 exhaust 1.5s. This would give you .576/.563" before lash, and I used .022/.024" HOT setting.
      Drag Race Solid Flat Tappet Cam - Chrysler 361-440 316/326-1
       
    • Red_Duster

      Red_Duster Well-Known Member

      Messages:
      248
      Likes Received:
      141
      Joined:
      Apr 17, 2019
      Location:
      California
      Local Time:
      5:58 PM
      Sounds pretty similar to my 440. I didn’t mill the domes of my TRWs and have the Promaxx head but I have the 296/.557 cam and it’s fun with the RPM intake and not soggy on the bottom end.
      If you go to different rockers, I’d be interested in the crane 1.5s, I have the ductiles on mine.
       
      • Like Like x 1
      1. This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
        By continuing to use this site, you are consenting to our use of cookies.