Why cam timing matters... Picture of King Motorsports Dummy Motor
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From: Jetsetter
Why cam timing matters... Picture of King Motorsports Dummy Motor
A picture is worth 1000 words. This is Chad's (our motor builder) dummy motor. We use it to check cam timing when working with wild set-ups that use custom cams/pistons. Yes, you can spin the motor over and actually watch the valve timing events. Enjoy...
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From: Jetsetter
Re: Why cam timing matters... Picture of King Motorsports Dummy Motor (Don Lackey)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Don Lackey »</TD></TR><TR><TD CLASS="quote">That picture is almost to good to post.</TD></TR></TABLE>
Yeah I'm giving away one of our motor building secrets.... better save it quick!
Yeah I'm giving away one of our motor building secrets.... better save it quick!
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From: The Blue Planet
Re: Why cam timing matters... Picture of King Motorsports Dummy Motor (Ausmith)
Thems some beefy valve springs mister! Thats the way to make horsepower, 2 lbs on the seat, 4 lbs over the nose! Gotta try that on my 11000 rpm build! Seriously, thanks for posting this 
. I come from the " assemble with light valve springs and clay school" myself. What you have there is one damn fine tool.
. I come from the " assemble with light valve springs and clay school" myself. What you have there is one damn fine tool.
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From: MoonSHINE Metropolis, .FL. Run Free, North America
Re: Why cam timing matters... Picture of King Motorsports Dummy Motor (SFWDcoupe)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SFWDcoupe »</TD></TR><TR><TD CLASS="quote">nice cut out!</TD></TR></TABLE>
I agree.
what specs are we looking at in particular on this picture?(pistons,rods,cams,gear settings,head,valves,block, rotating assembly/crank)
O,yeah.......what stoke/cycle is the motor on in the picture?
WOOOW. clearacnce looks like it almost makes piston/valve contact. I cant visually tell.
Very Nice.
I agree.
what specs are we looking at in particular on this picture?(pistons,rods,cams,gear settings,head,valves,block, rotating assembly/crank)
O,yeah.......what stoke/cycle is the motor on in the picture?
WOOOW. clearacnce looks like it almost makes piston/valve contact. I cant visually tell.
Very Nice.
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From: Mustafar
Re: (1 2 NV)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1 2 NV »</TD></TR><TR><TD CLASS="quote">get a cam fixture and you wouldnt have to worry about cutting up a block/head and looking at it.</TD></TR></TABLE>
Elaborate.
Elaborate.
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From: retired 2/13/10
B*a*n*n*e*d
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From: retired 2/13/10
Re: (Padawan)
did you see the second post i made in that thread? that is P2V clearancing. so yes the fixture will help properly. besides that motor cutout looks cool and all but its only good for 1 bore size and thats even if your crazy enough to disassemble it each and every time. then if you working on a different motor you will have to measure deck height and head height for each and every different motor combo. as i said, it looks cool but i dont think its as helpful as some may think. http://www.newenglandhondarebuilders.com/
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From: Mustafar
Re: (1 2 NV)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1 2 NV »</TD></TR><TR><TD CLASS="quote">did you see the second post i made in that thread?</TD></TR></TABLE>
No, I admittedly overlooked the portion regarding piston to valve clearance. It does appear to be a relatively accurate and somewhat easy method, though the inconsistencies you allude to in your original post indicate that the results should be used with an additional safety margin (which you also mention).
No, I admittedly overlooked the portion regarding piston to valve clearance. It does appear to be a relatively accurate and somewhat easy method, though the inconsistencies you allude to in your original post indicate that the results should be used with an additional safety margin (which you also mention).
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From: hamilton, ontario, canada
Re: Why cam timing matters... Picture of King Motorsports Dummy Motor (Ausmith)
you didnt make a standard thickness headgasket cutout??...or was that on purpose...you can really have some fun with making cross sections like that hehe...looks fantastic for a machine shop reference
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From: retired 2/13/10
Re: (Padawan)
it is very helpful cause as in that same post i had my P2V chart shown using my current skunk pro2s. when i used my JUN 3s last year the chart showed minimum clearances at around 9* BTDC and ATDC. as i said in that post besides VTEC being locked that motor was ready to run.
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From: Jetsetter
Re: (1 2 NV)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1 2 NV »</TD></TR><TR><TD CLASS="quote">did you see the second post i made in that thread? that is P2V clearancing. so yes the fixture will help properly. besides that motor cutout looks cool and all but its only good for 1 bore size and thats even if your crazy enough to disassemble it each and every time. then if you working on a different motor you will have to measure deck height and head height for each and every different motor combo. as i said, it looks cool but i dont think its as helpful as some may think. http://www.newenglandhondarebuilders.com/</TD></TR></TABLE>
Jeeze. I said above that it's useful for visually observing cam timing events when you are working with a custom camshaft. This is not how we check piston-to-valve, or valve-to-valve.
Jeeze. I said above that it's useful for visually observing cam timing events when you are working with a custom camshaft. This is not how we check piston-to-valve, or valve-to-valve.
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From: retired 2/13/10
Re: (Ausmith)
i understand what you are eluding too now.
either way properly plotting cam timing events in relationship to crank degrees is the proper way to do it and i know you know this. some people need it in black and white or they still wont understand.
either way properly plotting cam timing events in relationship to crank degrees is the proper way to do it and i know you know this. some people need it in black and white or they still wont understand.
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From: Jetsetter
Re: (1 2 NV)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1 2 NV »</TD></TR><TR><TD CLASS="quote">i understand what you are eluding too now.
either way properly plotting cam timing events in relationship to crank degrees is the proper way to do it and i know you know this. some people need it in black and white or they still wont understand. </TD></TR></TABLE>
Agreed. This tool was an eye opener when working with a custom cam AND piston combo. When you measure P2V you come up with an absolute number - the valve is x" from the piston at this given spot. But what you can not see is how the valve head relates to the piston ALL the way through its range of motion. On this particular set-up the absolute P2V was not the problem, rather Chad noticed that the valve came waaaaaay to close to the top edge of the pocket on its way down. Basically the pocket location had to be revised otherwise the smallest amount of error would have caused P2V contact at the top edge of the pocket, not at the bottom.
either way properly plotting cam timing events in relationship to crank degrees is the proper way to do it and i know you know this. some people need it in black and white or they still wont understand.
</TD></TR></TABLE>Agreed. This tool was an eye opener when working with a custom cam AND piston combo. When you measure P2V you come up with an absolute number - the valve is x" from the piston at this given spot. But what you can not see is how the valve head relates to the piston ALL the way through its range of motion. On this particular set-up the absolute P2V was not the problem, rather Chad noticed that the valve came waaaaaay to close to the top edge of the pocket on its way down. Basically the pocket location had to be revised otherwise the smallest amount of error would have caused P2V contact at the top edge of the pocket, not at the bottom.
