Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. mindenm

    Crankshaft Modification

    Brian, thank you for your analysis and the lesson. As I said from the beginning I was looking for both. Just by chance I stumble in that 190/170 split and did not know how it would play out. As you asked before, attached, please find a file with a 2 digs increment run if it is of any interest...
  2. mindenm

    Crankshaft Modification

    BrianPetersen, Thanks for your analysis. I still have a couple of questions. If "the amount of time that the stroke takes" in a cycle is different and the power one is longer, will it add to an engine efficiency eventually? If a piston moves slower then combustion volume increase is slower then...
  3. mindenm

    Crankshaft Modification

    140Airpower, hemi: Thanks for your suggestions. I'll try to follow. Meanwhile attached is one approach I am looking into for VCR.http://files.engineering.com/getfile.aspx?folder=e4cb8eb7-e429-472c-a95f-362a320d6ed5&file=Fig_Eng.pdf
  4. mindenm

    Crankshaft Modification

    140Airpower, hemi, kirrer and ... would you advise to try to build a model/prototype or you think it is not worth it? To build a VCR is definitely above my level even though I can model a mechanism in SolidWorks. Would appreciate any opinion. Thanks again
  5. mindenm

    Crankshaft Modification

    Thanks to everyone for looking into my project. 140Airpower, as you asked I ran both mechanisms thru a cycle by 15 deg. increments. Looks like piston moves slower in this design which, on the other hand, might add some as seen below. The first attachment in this thread indicates what and how...
  6. mindenm

    Crankshaft Modification

    Talking about complexity and gains how about this Honda engine? http://thekneeslider.com/honda-exlink-extended-expansion-linkage-engine/ Low side load on the cylinder and, yes, bigger difference between power and compression strokes. I think intake can be controlled by valves.
  7. mindenm

    Crankshaft Modification

    Kirrer, Thank you very much for bringing to my attention this useful verifying tool. This whole mechanism has a rocker/lever which works as a wheelbarrow. The wheel is moving up and down in a narrow guide/channel and works as a fulcrum. The first attached file shows a diagram which I used for...
  8. mindenm

    Crankshaft Modification

    140Airpower Thanks for taking time to look into it. Yes, there is no constrain in the guide-channel and the roller/fulcrum is moving up and down only. By manipulating dimensions of the crank's throw, arms of the rocker/lever, position of the guide and piston's offset I got the results which are...
  9. mindenm

    Crankshaft Modification

    Hi 140Airpower This time I'll try to show it to you in motion but again it is only an idea not a design in any way. I hope it will help. About the crank - it is only a diagram but I admit that quite a bit of work is needed to make it perform and that's why I asked the question and looking for...
  10. mindenm

    Crankshaft Modification

    Hi 140Airpower Here is URL of the original schematic I compared my idea against. http://www.epi-eng.com/piston_engine_technology/piston_motion_basics.htm I tried to upload the schematic of my idea to ENGINEERING.com. Hope you will be able to get it this way. It is only a schematic even...
  11. mindenm

    Crankshaft Modification

    Thanks to everyone who responded for your interest. Looks like I did not provide enough information. I tried to work against a schematic I found on the web: a crank throw of 2" i.e 4" stroke and a connecting rod 6.1" long. Practically 1 component is added to the crank. But the throw is smaller...
  12. mindenm

    Crankshaft Modification

    Hi all, I am neither an engine nor automotive engineer but recently using CAD I came up with a quite simple in my opinion addition to a crankshaft. It shows in that CAD model that power and intake strokes will last for 190 degrees of the crankshaft rotation but exhaust and compression ones- for...

Part and Inventory Search

Back
Top