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  • tussuck
    tussuck
    3 years ago
    Just keep in mind that some cams are good in baggers and others are good in lighter bikes.  I have always run an EV3 (or EV35 when on the turbo) and found them a good cam.  Solid performance from about 2800 rpm upwards to my normal rev lint of 5500 - but then can do 6000 no problem.
  • evo94
    evo94
    3 years ago
    evl 3010 ...quieter
  • fatbat
    fatbat
    3 years ago
    I wouldn’t split hairs over either and you’ll be happy one way or the other 
  • tussuck
    tussuck
    3 years ago
    Yep, Woods #6 or EV27 will keep you happy!
  • tussuck
    tussuck
    3 years ago
    Yep....EV13 has always been the goto choice for baggers!
    I would love to drop in a EV49 one day just for chits and giggles to see how it goes.
  • Grease Monkey
    Grease Monkey
    3 years ago
    Think Hoody ment a bagger for the 13, if I was you with the softail it would be the 27 for sure.
  • Grease Monkey
    Grease Monkey
    3 years ago
    Take note of what Hoody has said in his posts, free advice from one that knows wtf he is talking about.
  • tussuck
    tussuck
    3 years ago
    Good call and a good build for a little extra omph.  If you can spring it then its worth shaving a few thou off the heads as well - Evos respond REALLY well to nudges on compression.
  • 408
    408
    3 years ago
    Hoody suggested you could check the squish. That is the first thing you should do before thinking about shaving your heads.
    You can bump compression by reducing your head gasket thickness.
    You can also reduce your base gasket thickness. Stock is 0.020", Cometic make a 0.010"base gasket. I run pigtails with a smear of Yamabond.
    This is all stuff you can do yourself with a bit of reading up. And use the Big Boyz calculator to see where your compression is.
  • 408
    408
    3 years ago
    You looked at the twin cam calculator. There is a compression calculator for Evos.
    Plenty of articles about checking your squish. You need to have a basic understanding about checking your compression before you go any further.
    Checking your squish will give you an idea how to proceed with head gasket and base gasket thicknesses.
    A couple of different manufacturers make pigtails to bridge the oil line gap between the cases and the cylinders to nullify oil weeps at the base gasket.
  • tussuck
    tussuck
    3 years ago
    Checking the squish is removing the heads and putting plasticine on the piston crown and then reassembling with new gaskets etc and then turning over by hand so the valves make impressions in the plasticine.  You then remove the heads and section the plasticine to see how close the valves came to the piston as well as the depth of the flat squish zone.

    The operation of shaving the heads is easy for a good shop to do as they set it up in the milling machine and basically cut 20-50 thou of the head surface.  Might be a couple of hundred bucks - but tbh I have no idea on cost.  Do you stop there and then also do a 5 able valve job as well.  

    I do always reseat the valves and lap them in when removing the heads as its something anyone can DIY. 

    It may be easier to just run thinner head gaskets sometimes.  (make sure to turn the engine over manually before firing up to make sure nothing is binding or touching)


  • 408
    408
    3 years ago
    Quoting tussuck on 15 Aug 2022 12:02 AM

    Checking the squish is removing the heads and putting plasticine on the piston crown and then reassembling with new gaskets etc and then turning over by hand so the valves make impressions in the plasticine.  You then remove the heads and section the plasticine to see how close the valves came to the piston as well as the depth of the flat squish zone.


    The operation of shaving the heads is easy for a good shop to do as they set it up in the milling machine and basically cut 20-50 thou of the head surface.  Might be a couple of hundred bucks - but tbh I have no idea on cost.  Do you stop there and then also do a 5 able valve job as well.  

    I do always reseat the valves and lap them in when removing the heads as its something anyone can DIY. 

    It may be easier to just run thinner head gaskets sometimes.  (make sure to turn the engine over manually before firing up to make sure nothing is binding or touching)



    That is not checking squish, that is checking piston to valve clearance.
    Checking squish does not require having heads in place, just checking the position of the piston at tdc relative to the cylinder.
    The gasket and cylinder stack height is adjusted for the required squish.
  • John.R
    John.R
    3 years ago
    You can't assume anything, all has to be measured.

    Measuring the deck height on my cast pistons was bit annoying.

    Deck height and squish are different though.
  • John.R
    John.R
    3 years ago
    For a drop in cam they won't bother. 

    Think we're gettin lost in the sauce a bit, just throw a cam in it and run it.
  • 408
    408
    3 years ago

    We haven't got on to domed pistons yet....
  • beaglebasher
    beaglebasher
    3 years ago
    I am trying to catch up with this thread.  What  is this "SQUISH" thing?
    Its a term I am not familiar with. I have a fair idea what it is but for the benefit of everybody on the forum " SQUISH "  needs to be explained.  I cant be fucked googling it.

  • WideglidingNZ
    WideglidingNZ
    3 years ago
    Quoting beaglebasher on 15 Aug 2022 09:53 AMedited: 15 Aug 2022 10:01 AM

    I am trying to catch up with this thread.  What  is this "SQUISH" thing?

    Its a term I am not familiar with. I have a fair idea what it is but for the benefit of everybody on the forum " SQUISH "  needs to be explained.  I cant be fucked googling it.

    https://en.wikipedia.org/wiki/Squish_%28piston_engine%29 hopefully this explanation might help
  • 408
    408
    3 years ago
    Quoting beaglebasher on 15 Aug 2022 09:53 AMedited: 15 Aug 2022 10:01 AM

    I am trying to catch up with this thread.  What  is this "SQUISH" thing?

    Its a term I am not familiar with. I have a fair idea what it is but for the benefit of everybody on the forum " SQUISH "  needs to be explained.  I cant be fucked googling it.


    Here you go Beagle, in basic terms, this is how I understand the 'squish' process and what it does.
    On the intake stroke, the downward travel of the piston creates a vacuum which draws air into the cylinder via the intake valve. As the intake charge goes past the injectors, they are firing a fuel mist into the intake air stream and some mixing of the air and fuel takes place. Mixing also takes place when the fuel is bounced off the walls of the intake manifold, the back of the valve, and the valve stem. The fuel has to undergo a change from liquid to gas.
    The piston and cylinder have a circular cross section while the head has an egg shaped cross section at the cylinder interface. The egg shape accommodates the valve movement of the exhaust valve and the larger intake valve and the circular shape 'reduces' from the sides and the head effectively forms a 'part ceiling' at the sides of the cylinder.
    When the piston travels up on the combustion stroke, some of the air fuel mix is squashed between the piston and the part ceiling of the head and is forced out into the combustion chamber. This turbulence contributes substantially to the complete mixing of the air-fuel mix.
    The 'squish' is the gap between the piston at tdc and the underside of the head.
    If the piston edge at tdc is flush with the top of the cylinder then you have zero deck height and the squish is set by the thickness of the head gasket.
    If the piston at tdc is below the top of the cylinder by a couple of thou, then the squish is increased by that distance.
    If the piston is above the cylinder surface by a couple of thou, then the squish is decreased by that distance.
    Some articles refer to a squish of 1mm (0.040"), many harley performance builds aim for 0.030".
    Together with the pressure and the heat, a good squish and increased turbulence in the combustion chamber provides more complete fuel mixing, better combustion, combustion efficiency, and less carbon build up in the combustion chamber.
    It is also possible to run slightly higher compression with this improved efficiency, which provides more power.
  • 408
    408
    3 years ago
    OK , some pics might help. Found some pics of 110 heads on ebay.
    The squish area is the area between the circular outline of the head gasket and the yellow line.

    110 head.png
    110 head squish band.png
  • beaglebasher
    beaglebasher
    3 years ago
    Quoting beaglebasher on 15 Aug 2022 09:53 AMedited: 15 Aug 2022 10:01 AM

    I am trying to catch up with this thread.  What  is this "SQUISH" thing?

    Its a term I am not familiar with. I have a fair idea what it is but for the benefit of everybody on the forum " SQUISH "  needs to be explained.  I cant be fucked googling it.

    Quoting 408 on 16 Aug 2022 01:32 AM


    Here you go Beagle, in basic terms, this is how I understand the 'squish' process and what it does.
    On the intake stroke, the downward travel of the piston creates a vacuum which draws air into the cylinder via the intake valve. As the intake charge goes past the injectors, they are firing a fuel mist into the intake air stream and some mixing of the air and fuel takes place. Mixing also takes place when the fuel is bounced off the walls of the intake manifold, the back of the valve, and the valve stem. The fuel has to undergo a change from liquid to gas.
    The piston and cylinder have a circular cross section while the head has an egg shaped cross section at the cylinder interface. The egg shape accommodates the valve movement of the exhaust valve and the larger intake valve and the circular shape 'reduces' from the sides and the head effectively forms a 'part ceiling' at the sides of the cylinder.
    When the piston travels up on the combustion stroke, some of the air fuel mix is squashed between the piston and the part ceiling of the head and is forced out into the combustion chamber. This turbulence contributes substantially to the complete mixing of the air-fuel mix.
    The 'squish' is the gap between the piston at tdc and the underside of the head.
    If the piston edge at tdc is flush with the top of the cylinder then you have zero deck height and the squish is set by the thickness of the head gasket.
    If the piston at tdc is below the top of the cylinder by a couple of thou, then the squish is increased by that distance.
    If the piston is above the cylinder surface by a couple of thou, then the squish is decreased by that distance.
    Some articles refer to a squish of 1mm (0.040"), many harley performance builds aim for 0.030".
    Together with the pressure and the heat, a good squish and increased turbulence in the combustion chamber provides more complete fuel mixing, better combustion, combustion efficiency, and less carbon build up in the combustion chamber.
    It is also possible to run slightly higher compression with this improved efficiency, which provides more power.

    My head is fuckin sore
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