Page 61 of 61 FirstFirst ... 1151596061
Results 601 to 605 of 605

Thread: Powerplus or Bust, Eh?

  1. #601

    Default

    Quote Originally Posted by TechNoir View Post
    Ha, i was going to guess duration but then thought that was too obvious so didn't bother.

    As for a solution. What i would do is go back to basics. You have published data for timing so i would get it as close to thst as i could first. Then see how it rides. Then see if any published tuning data makes a difference, testing small timing changes one at a time. (All assuming that you are 100% happy with ignition timing). Then, if you think lift might be an issue i would use a spare set of cams and make small changes and test incrementally. Being a side valve at least you dont need to worry about valve/piston clashes.

    John
    Good discussion John. Obviously, you can't change duration just by adjusting Cam timing. You can set the valve events later or sooner, but open and close will both change in the same direction, so duration won't be affected. So, as you alluded to, the Cam would have to be reground, ...or some other physical change made. My cam is in good original shape, so I'm focusing on the components that were not in good shape... something that could affect both timing and lift...

    Does that bring anything to mind? I know this question probably isn't fair, because it would require detail knowledge of Indian PowerPlus motors specifically. Still, we're having fun here, right?



    Kevin


    .

  2. #602

    Default

    Quote Originally Posted by T. Cotten View Post
    As you surely know, Kevin,...

    Tight nuts mean nothing to a vacuum leak.
    Especially with the evil pinch slots at the bottom of the manifold.

    And spraying stuff while running only shows big leaks, not the little leaks waiting to bite you, or rob you of performance.
    Bubbles don't let anything get by..

    Never does only one thing go wrong at a time.

    ....Cotten

    Agreed; a bubble test is the best way to find vacuum leaks.




    Kevin


    .

  3. #603
    Join Date
    Jul 2012
    Posts
    315

    Default

    Quote Originally Posted by Shaky Jake View Post
    My cam is in good original shape, so I'm focusing on the components that were not in good shape... something that could affect both timing and lift...

    this question probably isn't fair, because it would require detail knowledge of Indian PowerPlus motors specifically.
    I don't have even superficial, let alone detailed, knowledge of any Indian motor. But the shape of cam followers definitely affects timing (although, not lift...)... Oh, wait, yours is a flathead engine so there are no followers. Or are there? If the valve stems ride directly on the cam like in a "normal" flathead engine my guess makes no sense.

    p.s. motivated by your offer of a $100 prize (you did offer a $100 prize, didn't you?...) I googled Powerplus engines. All I could find were low resolution images but there is something that looks suspiciously like a rocker arm under the inlet valve. I can't tell what it really is, or how it works, but if there is a rocker arm of sorts between the cam and the valve stem that could explain both the incorrect duration as well as wrong lift. But, maybe what looks like a rocker arm is just a valve lifter(?).
    Last edited by BoschZEV; Today at 01:13 PM.

  4. #604
    Join Date
    Jun 2001
    Location
    Central Illinois, USA
    Posts
    3,117

    Default

    Just promise you will do it, Kevin!

    Was there really no seals between the spigots and the cylinder nipples?

    ...Cotten
    Attached Images Attached Images
    AMCA #776
    Dumpster Diver's Motto: Seek,... and Ye Shall Find!

  5. #605

    Default

    Quote Originally Posted by BoschZEV View Post
    I don't have even superficial, let alone detailed, knowledge of any Indian motor. But the shape of cam followers definitely affects timing (although, not lift...)... Oh, wait, yours is a flathead engine so there are no followers. Or are there?
    Ding ding ding ding! I'm going to call that a win, even though you almost talked your way out of it at the end. Sorry, no cash prize. And, of course, I am assuming that I am correct about the cause of the problem, which still remains to be proven. But yes, the Powerplus cam followers can affect valve timing and lift.

    The Indian PowerPlus does indeed have a kinematically complicated system of Cam Followers and valve lifters, especially on the Intake side. They all rotate on pins, and there are various arcs and planes that interact with each other by pushing and sliding contact. They do, of course, wear, and they are all old. So in order to use them reliably, you have to recondition them in some way. When you recondition them, you remove a small amount of material, which affects the way in which they interact with each other, by changing their position with respect to each other. In the end this affects angles and ratios and the like. I've spent much time watching them move, and I am convinced that this is the source of my problem. I'll post some pictures later.

    So, I spent two weeks teaching myself CAD, and I began reverse engineering the Cam Followers and valve lifts. I have finished my Intake Cam Follower design, which is intended to duplicate an original part. I have given it to a machinist who has a full on CNC machining center in the machine shed behind his farm house (you gotta love Nebraska). For this first run, I asked him to just make me one Follower out of a soft steel so I can test the geometry and make adjustments as needed. I have had some original ones hardness tested, and the final parts will be made from a suitable hardenable steel that can be heat treated to the same hardness as the originals.

    I got a call from my machinist earlier today, and I'm going to meet with him this afternoon to get the first test Follower.


    Details to follow.




    Kevin


    .

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •