What Cam is in my 85 EVO ?

Discussion in 'Engine, Fuel and Exhaust' started by BOBFLHTC, Aug 25, 2010.


    BOBFLHTC Active Member

    I am considering changing cams this winter and I'm not sure which cam I currently have. Apparently there are 5 options for EVO's. I'm not sure if its a 84-87 or 81-91 (L). The non CA and pre 92 apparently have more Valve Lift
    Thanks Bob

    84-93 CA
    92-98 (N)
    81-91 (L)
  2. ultrat

    ultrat Senior Member Contributor

    in 93 fl went w/ andrews 23....i tried red shift came on to late....good luck';';';

    BOBFLHTC Active Member

    I'm looking at the chart and the EV23 has .498 lift for the Intake and Exhaust

    Did you pick up power on the low end ? Did you sacrifice too much on the high ? Was it much different than stock ?

  4. HDDon

    HDDon Experienced Member Contributor Retired Moderators

    I'm not sure if it will answer your question but Andrews reccommened that I use their EV-27. I have a '94FLSTC Evo, and I have always liked the way it runs.
  5. ultrat

    ultrat Senior Member Contributor

    sorry its been a while 27 not 23...23 lighter bikes.. I get # mixed up dyslectic,,,,, came on at low end did sacrifice on high end.. get one that closes intake about 30 deg...
  6. Breeze3at

    Breeze3at Well-Known Member

    Bob; The EV27 has a tiny bit less lift (.495/.495) and a little more duration
    (236/240 vs. 220/228). It was a popular cam for heavier bikes, and is bolt in. Andrews used to have an informative web site, I haven't looked at it in years.
    You can also find good sales on Andrews cams by shopping around.
  7. Jack Klarich

    Jack Klarich Guest

    Check with Hoople, I loaned him my Big Twin High performance guide He can look it up for you, Jack:s

    BOBFLHTC Active Member

    Thanks for the feedback. It does seem that many are happy with EV27.

    I saw this site about performance tuning which if accurate was helpful.

    Making More Horsepower

    Valve Lift
    The more lift your cam has, the more fuel/air mixture gets in your engine but If your cam has more than 1/2 inch of lift, the stock valve springs bind.

    Stock Harley cams have no overlap. The longer the valves are open, the higher the rpm at which the cam is effective.
    Less duration will produce more low end torque and less top end horsepower; more duration will produce less low end torque and more top end horsepower.

    Since I have 2 into 1 pipes it suggests my peak torque has moved up in Rpm's so I would want a cam with:

    Less Duration (more Low end torque),
    More Valve Lift (more fuel and air)
    More Overlap (more efficient)

    I sent a email to Andrews for a recommendation. It looks like EV23 might be a possibility too

    Thanks Bob

    BUBBIE Well-Known Member

    I know IF the intake Closes Earlier you get More LOW End torque Like ultrat says..

    I am going "Playing" with a 4* sprocket on/for my 09 FLHR.. Idea is to MOVE the intake to Close at an earlier Number.. for the torque to come on a bit earlier.
    When I put in SE255 cams, I Like the results BUT would rather they come on a little earlier for my Heavy Bike..
    I am going to order the andrews 4 degree +- engine sprocket (17 tooth) and see what it does for my full stage One with TFI..

    If it does what Steve 07 has done or close (he used SE254 cams with the 4* sprocket) claims Much More Low End!

    I will POST a new thread when I find out "How It Works"

    Part # that TQ1 furnished me is andrews #216323...

    For your EVO, I believe you are right on track with the 23 or the 13 but NOT the 27 cam. REMEMBER most people Over Cam and that does not give better results,,, It Takes away!

    EV23 = 10/30 on intake lift 498/498
    EV13 = 15/31 on intake lift 485/495
    EV 27 = 20/36 on intake lift 495/495

    Proper compression and volumes are needed to get results with Bigger cams and usually the RPM band Moves Way Up where you don't need/want it for a heavy bike.

    I would like the cam to start on the LOWEST RPM when Just thinking Cam!!
    Especially on the heavy bikes...

    I would go with the EV23 IMHO on the three that Could be used on your bike... The intake closes earliest! Along with the highest Lift.


    BOBFLHTC Active Member

    I emailed Andrews support with this description:

    I'm looking to replace the cam on my stock 1985 EV80 FLHTC. It has a S&S E carb with free flowing filter, SE ignition module, 2 into 1 Patriot Defender exhaust. My riding preference: touring, sometimes 2 up, almost never over 3500 rpm or 70 mph. I don't wind the gears out

    and they recommended the EV13. I understand it runs cooler due to the longer exhaust duration. I wonder if its a significant difference ? Thanks Bob