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how do you make a flathead sound "loopey"

Discussion in 'The Hokey Ass Message Board' started by snortonnorton, May 26, 2006.

  1. snortonnorton
    Joined: Sep 18, 2004
    Posts: 889

    snortonnorton
    Member
    from Florida

    how do you build a flathead to dound "loopey"?

    is it the 4 inch mercury crank, the more numberous carbs, or other modifications or the combination of all of them?

    i like how some of them sound...

    usually it's how long the stroke is of an engine that makes it sound loopey right? but that can't really be changed, can it? or are flatheads already longstroke engines?
     
  2. wheelkid
    Joined: May 25, 2006
    Posts: 1,263

    wheelkid
    Alliance Vendor
    from Fresno, CA

    It's the overlap on the cam
     
  3. repoman
    Joined: Jan 2, 2005
    Posts: 1,276

    repoman
    Member

    What the kid said.

    The lobe separation angle is the key number (besides lift). The same cam with say, .500 lift with a 114 angle will idle smoother than the same lift/duration with a 108 angle.

    For the sickest 'sound', that is drivable, pick a cam with moderate lift, but a 104-106 separation angle, and run as much compression as possible on the gas you can afford. Bear in mind that running a 104 cam will allow more compression that a wide cam.

    High compression also adds to the right 'sound'.
     
  4. I think you mean "lopey" as in lope as in a slow pace of running or pertaining to horses means a 4 beat gait as all 4 hooves hit the ground separately.
    Loopey or "loopy" is crazy or strange behaviour like when you get kicked in the head by a horse.
     
  5. repoman
    Joined: Jan 2, 2005
    Posts: 1,276

    repoman
    Member

    I think a .500 cam @104 in a small bore sub-300" engine will qualify as "loopey" :D

    The #32 "Rambler Rebel" car that was at the roundup had so much cam it had no idle. He had to start it, move up in line, then it would die. It only ran when he had his foot in it :D Best sounding flatty I ever heard. Even the cam timing was trad!
     
  6. seymour
    Joined: Jan 22, 2004
    Posts: 5,125

    seymour
    Member
    from PNW

    An aluminum flywheel never hurts either.
     
  7. flatoz
    Joined: May 11, 2003
    Posts: 3,237

    flatoz
    Member

    cant say I have seen a 500 lift cam in a flathead. Most of the commonly available heads only have 425 thou clearance from deck to top of combustion pocket.

    check out scneider cams. they have a wide variety.

    I am going to run a L100 in my blown motor I am going to build.

    Dont forget isky they still make cams for flatheads.
     
  8. "Doc" Parsons
    Joined: Jun 26, 2005
    Posts: 342

    "Doc" Parsons
    Member

    Or you could pull 3 plug wires and let it catch up with it self , it would really sound different
     
  9. repoman
    Joined: Jan 2, 2005
    Posts: 1,276

    repoman
    Member

    I was just talking theory. I don't know a flathead from an anvil.

    Someone else than me should pick your cam!
     
  10. Repoman is absolutely right about the theory, but the specs he quoted were appropriate for an OHV engine like a 350 SBC. Talk to an experienced flathead builder about a cam with modest duration and lift, but with a narrow Lobe Separation Angle (LSA).
     
  11. flatoz
    Joined: May 11, 2003
    Posts: 3,237

    flatoz
    Member

    I realise that, but then I know flathead cams, I get the feeling that snortonnorton doesnt, so I just wanted to point out to him to do some research before he goes and buys a cam.

    and as has been said before, a flathead isnt an overhead valve, so the duration etc is differnt to OHV motor. I havent got the info on my cam handy to post it. but if you want to talk cams, go over to fordbarn and do a search, there has been plenty of talk there and you should find what you want.

    cheers.
     
  12. Bruce Lancaster
    Joined: Oct 9, 2001
    Posts: 21,681

    Bruce Lancaster
    Member Emeritus

    Talk to Ol' Ron, on here and on the barn; he is THE cam guru.
    By the way, someone over there is reprinting Ron's book!
     
  13. 327-365hp
    Joined: Feb 5, 2006
    Posts: 5,437

    327-365hp
    Member
    from Mass

    You can use a 500 lift cam but you gotta run extra head gaskets... HAHA
     
  14. Flatman
    Joined: Dec 20, 2005
    Posts: 1,975

    Flatman
    Member

    Isky Max 1 ! Just the right amount of "lumpy" at idle:cool: and that man knows his flattie cams.

    Flatman
     
  15. 4tl8ford
    Joined: Sep 1, 2004
    Posts: 1,087

    4tl8ford
    Member
    from Erie, Pa

  16. buffaloracer
    Joined: Aug 22, 2004
    Posts: 823

    buffaloracer
    Member
    from kansas

    Or you could pull the choke knob out.
     
  17. snortonnorton
    Joined: Sep 18, 2004
    Posts: 889

    snortonnorton
    Member
    from Florida

    yeah, i've read that the 400JR is the best all around one, right?

    thanks for the link to the sound, that's awesome..

    this site freaking rules, i feel like without the Hamb, i would never have been inspired enough to begin this journey. YOU GUYS RULE!! since i didn't grow up in california or Ohio, I would never have seen a traditional hot rod without this site.. LOL
    florida sucks, it's all gold chainers with glass cars except for the cool people like the rumblers and stuff. Go Nads!!
     
  18. cruzr
    Joined: Jan 19, 2006
    Posts: 3,127

    cruzr
    Member Emeritus

    i run a isky bumpstick 400 jr in my flatty, sound is cool
     
  19. snortonnorton
    Joined: Sep 18, 2004
    Posts: 889

    snortonnorton
    Member
    from Florida

    yeah, that's what i'm hearing. cool as hell. sounds cooler than any sbc i've heard, even with a super charger.

    kind of like my long stroke norton commando...

    it's one of the longest strokes of any bike. i get a boner when i start it... LOL
     
  20. George G
    Joined: Jun 28, 2005
    Posts: 1,275

    George G
    Member

    Literio L 100
     
  21. hmm,

    a timely question indeed seeing as im toying with the idea myself. hmm what to do what to do....

    my research indicates the 400jnr is a great cam whilst the max 1 has been described as almost useless, or very close to stock. the potvin 3/8 has alot of fans as does the very popular L100. day dreams day dreams...

    Danny
     
  22. Flatdog
    Joined: Jan 31, 2003
    Posts: 1,285

    Flatdog
    Member Emeritus

    Max 1 is a great cam,a 400jr will outrun it but not by much.
     
  23. Hey Flat,

    I cant really talk mine is still stock! I remember a discussion on fordbarn where some of the guys were saying the max 1 is really close to stock feeling but its probably dependant on so many variables, induction, ignition, weight of the vehicle, gearing etc etc.

    What cams have you run before? I'm still thinking about what to get for mine...

    Danny
     
  24. Relay
    Joined: Apr 21, 2006
    Posts: 304

    Relay
    Member

    i've found when you take off a plugwire it makes the car sound really looooopy
     
  25. Muttley
    Joined: Nov 30, 2003
    Posts: 18,501

    Muttley
    Member

    Thats how I sound after an order of chili fries.
     
  26. snortonnorton
    Joined: Sep 18, 2004
    Posts: 889

    snortonnorton
    Member
    from Florida

    LOL, you guys are funny.

    I'm thinking Isky jr 400 is the way to go from what i'm hearing..... that and changing the valves to chevy 1.6 valves with adjustable lifters and then the engine should really be loud to show off the lopeyness... LOL

    now carbs i'm going to have to research, but most like the dual 97 strombergs, right?
     
  27. 94s work very well and they are alot cheeper...and a better carb dare i say?

    Danny
     
  28. blown49
    Joined: Jul 25, 2004
    Posts: 2,212

    blown49
    Member Emeritus

    You'll prolly have to also budget for a new dizzy as well. Original dizzy may be a problem with vacuum advance after adding dual carbs.
     
  29. Flatdog
    Joined: Jan 31, 2003
    Posts: 1,285

    Flatdog
    Member Emeritus

    Phy,I have run Max 1 400jr MCF 7/8 grind,and CRower roller,MCF ran the best.Crower is only one I ran with without blower.Don,t think it wild enought but ran well with blower.Have a wilder roller for next motor.Don't get wrong idea about performace ALL of the above cams ran well if I had to pick one for the average guy it would be Max 1.MAybe L-100 or Snider I keep hearing good about.
     

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