mopar1rules Posted October 18, 2008 Report Share Posted October 18, 2008 (edited) i'd like to hear what you have to say there deckheight..... :smile: i mean .02 :biggrin: Edited October 18, 2008 by mopar1rules Quote Link to comment Share on other sites More sharing options...
'04limited Posted October 18, 2008 Report Share Posted October 18, 2008 What is the compression, what is the timing, are you running methanol or gas? my compression is at 142 timing +4 and running on pump gas. it runs great. Quote Link to comment Share on other sites More sharing options...
deckheight Posted October 19, 2008 Report Share Posted October 19, 2008 Squish clearance is just one factor in determining a Maximum Squish Velocity or "MSV". MSV is a measurement of the speed at which end gases are traveling toward the center of the combustion chamber as the piston nears top dead center. The speed these gases are traveling determines how much turbulance is taking place within the combustion chamber at a given degree of crankshaft rotation, which in turn indicates how well the gasoline and air are mixed or "atomized" within that fuel charge. The amount of atomization determines how fast the flame front initiated by the spark plug will travel, which in turn, along with ignition timing, fuel octane, etc. determines at what degree of crankshaft rotation maximum combustion chamber pressures occur. Ideally, maximum chamber pressures are reached very near top dead center of piston travel, too early and and the piston will be wasting inertia, as well as creating excessive heat, to overcome the chamber pressures as it passes TDC. To late and the gases from the expanding fuel charge are exerting less force on the piston since it is already traveling away from them as the piston moves back down the bore. The excessive heat generated by too early of a maximum chamber pressure is what causes uncontrolled "detonation" as the fresh fuel charge begins to spontaneously ignite from the excessive heat before the spark plug initiates the burn. These uncontrolled flame fronts then collide against each other pushing the piston around lateraly as well as generating even more heat and so on... Until the piston and rings eventually scrape away the film of oil between the piston and cylinder and it is metal to metal. Anyway, is that about as clear as as mud so far? i'd like to hear what you have to say there deckheight..... :smile: i mean .02 :biggrin: Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted October 19, 2008 Report Share Posted October 19, 2008 Anyway, is that about as clear as as mud so far? nope, totally got it. thanks for the info. :thumbsup: Quote Link to comment Share on other sites More sharing options...
deckheight Posted October 19, 2008 Report Share Posted October 19, 2008 I figured you would get it Mopar :ermm: Not that I think I am some kind of "rocket surgeon" or anything, quite the opposite actually. After reading it again this morning though... If it sounds like I am trying to be a know it all or a smartass or something... I am not! Some of the stuff is just hard to explain in general terms I guess. I have read several post on here lately about MSV's and/or sqush clearances and fuel octanes and ignition timing, etc. where apparently the poster was trying to make some sense of it... Just thought I would take a stab at it is all. I have actually retained a couple things (usually learned the hard way...) over the past couple decades... Quote Link to comment Share on other sites More sharing options...
mopar1rules Posted October 20, 2008 Report Share Posted October 20, 2008 i'm keeping my eyes peeled for that honing head, but haven't come across anything yet. Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted October 20, 2008 Report Share Posted October 20, 2008 Squish clearance is just one factor in determining a Maximum Squish Velocity or "MSV". MSV is a measurement of the speed at which end gases are traveling toward the center of the combustion chamber as the piston nears top dead center. The speed these gases are traveling determines how much turbulance is taking place within the combustion chamber at a given degree of crankshaft rotation, which in turn indicates how well the gasoline and air are mixed or "atomized" within that fuel charge. The amount of atomization determines how fast the flame front initiated by the spark plug will travel, which in turn, along with ignition timing, fuel octane, etc. determines at what degree of crankshaft rotation maximum combustion chamber pressures occur. Ideally, maximum chamber pressures are reached very near top dead center of piston travel, too early and and the piston will be wasting inertia, as well as creating excessive heat, to overcome the chamber pressures as it passes TDC. To late and the gases from the expanding fuel charge are exerting less force on the piston since it is already traveling away from them as the piston moves back down the bore. The excessive heat generated by too early of a maximum chamber pressure is what causes uncontrolled "detonation" as the fresh fuel charge begins to spontaneously ignite from the excessive heat before the spark plug initiates the burn. These uncontrolled flame fronts then collide against each other pushing the piston around lateraly as well as generating even more heat and so on... Until the piston and rings eventually scrape away the film of oil between the piston and cylinder and it is metal to metal.Anyway, is that about as clear as as mud so far? You forgot the part about keeping the piston from hitting the head. :biggrin: Quote Link to comment Share on other sites More sharing options...
deckheight Posted October 20, 2008 Report Share Posted October 20, 2008 LOL! Guess I forgot about that part... :biggrin: :biggrin: Where exactly is Bonny Lake WA. BTW? Couldn't find it on the crummy map I have... Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted October 21, 2008 Report Share Posted October 21, 2008 Around Sumner and puyallup. Map Link Quote Link to comment Share on other sites More sharing options...
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