FOPAR: I have a BOLO out on it…It is around here somewhere.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Ed: Gone Fish'in.

Be back with check of numbers once #1 intake lifter is nestled in its hole.
Hopefully it will happen in this life time...

Bill

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Success!!!!

All it took was a length of #12 copper wire, and a length of # 6 copper wire, a little itty-bitty LED light, 90 seconds, and Bob’s your uncle. That sucker is back in place.

Bill

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

[quote]I'm trying to decipher your numbers using the calculator in the Dyno2000 program.

Numbers aren't making sense.

Your intake duration seems too small with too much lift, and the exhaust seems duration seems too long (lift about right).

Can't figure out what numbers to put into program.


It wants:
Intake Valve open as degrees Before TDC
Intake valve close as degrees After BDC (bottom dead center)
Exhaust valve open Before BDC
Exhaust valve close After TDC


Can you translate to these figures?[/quote]


Ed, I hope these numbers are better. I guess I’m a bit confused as to which numbers to record where the wheel is two 180 degree scales indexed from TDC, and a second ring of smaller numbers indexed from BDC. Previously I was recording TDC indexed degrees.

The wheel is zero @ TDC in line with timing marks on pulley and chain cover using piston stop method of finding TDC. There appears to be no slop in timing chain. Dial indicator is aligned in X & Y axis to push rod centered in rod hole of head. No sticking of lifters, so I think my set-up is accurate.
_______________________________________
Intake valve open BTDC 76* or start of ramp
Intake valve closed ABDC 70* or end of ramp
Duration 354*

Intake full lift, or center line 96*
Total lift at lifter 0.321â€￾, or at valve 0.481.5â€￾

@ 0.050â€￾
Opening BTDC 55*
Closing ATDC 145*
Theoretical Center [55+145] / 2 = 100*
_____________________________________
Exhaust valve open BBDC 103*
Exhaust Valve close ATDC 75*
Duration 352*


Exhaust full lift, or Center line 104*
Total lift at lifter 0.322â€￾, or at valve 0.483â€￾

@ 0.050â€￾
Opening ATDC 157*
Closing BTDC 68*
Theoretical Center [157+68] / 2 = 112.5*
____________________________________

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Something funky still.....or you have a wayyyyyy big cam with low lift.

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Yeah....Im the one who destroyed this rare, vintage automobile.....

Many, but not all, mechanical cams have their advertised duration given at at .006" tappet rise. Please give the opening and closing points at .006" tappet rise and .050" tappet rise.

_________________
Joshua

I bet you're just luv'n all us back-seat mechanics right now.............

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Hi Josh,

When you say "Tappet Rise", would this be measuring off the lifter? If so I have listed 0.050â€￾ open & close events for intake & exhaust.

These lobes on this cam have long slow starting & ending slopes.

_____________________
Intake @ 0.006" lift

Opening BTDC = 52*
Closing ATDC = 97*
Duration 315*

_________________________
Exhaust @ 0.006"

Opening ATDC = 97*
Closing BTDC = 47*
Duration 310*
_______________________

Hope this is what you were looking for.

Bill

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Ed, this exercise would be easer if I had a cam card to compare to as measurements were being made. I’ll get through this with your help.

Bill

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Bill,

Sorry, but your numbers don't make sense. If the intake valve opens say 10° BTDC and closes 40° ATDC the valve is open 230°. 10+180+40=230 You give an opening of 52° BTDC and closing of 97° ATDC. 52+180+97=329 not the 315° you listed.

If this is an old cam design the recommended lash could be pretty wide and make the .006" tappet (lifter) rise numbers look pretty wild.

Your .050" numbers don't look right either. There is no way the intake valve opens 76° BTDC. Closing 70° ATDC is less ridiculous. Even if these valve events were accurate that's 326° intake duration not the 354° you give.

Let give an example of a pretty healthy Mopar Performance cam. This cam opens the intake valve 34° BTDC, closes it 62° ATDC. Exhaust opens 66° BBDC and closes it 30° ATDC.

The overlap is easy to find. The intake valve opens 34° BTDC and the exhaust closes 30° after so the overlap is 64°. Intake duration is 34+180+62=276°. Exhaust duration is 66+180+30=276°.

As you can see your numbers are really far off from our example.

Here are some links that may help.

http://www.tildentechnologies.com/Techn ... asics.html
http://www.rbracing-rsr.com/camshaft.html

_________________
Joshua

I knew he could finger it out!!!

Kind of reminds me of that old joke about the proctologist that became an auto mechanic...but I digress...

-D.Idiot

Josh,

I had a misunderstanding of the 0.050â€￾ measurement. I took it to be 0.050â€￾ down from nose, and not 0.050â€￾ of lift along ramp. So that was one discrepancy generated.

Thanks for the hand-outs, quite helpful. I hadn’t seen those sheets. I was using two other sets of directions, as the ones the came with my kit were rather brief, and were asking to compare readings to one’s cam card.

Bill

Intake:

@ 0.050â€￾ lift
Opening BTDC 18*
Closing ABDC 142*
Tappet lift 0.321â€￾
Intake Center line:
Measured 0.050â€￾ down each side of lobe. [C + O] / 2= Center*
[145 + 54] / 2 = 99.5*


Exhaust:
@ 0.050â€￾ lift
Opening BBDC 130*
Closing ATDC 5*
Tappet lift 0.324â€￾
Center line [158 + 68] / 2 = 113*

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Bill,

I think you're adding 90° to the intake closing and exhaust opening events. An intake opening of 18° BTDC is perfectly reasonable, and a closing of 52° would be about right giving a 250° duration at .050" lifter rise. That's a pretty long duration cam.

Going down .050" from peak lift is used to find the relative centerlines of the intake and exhaust lobes. Using that information is a good way to calculate the lobe centerline which is sometimes referred to the lobe displacement angle.

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Joshua

Josh,

I’m growing tired of this kicking my six. My degree wheel is split up into several scales running to 180 degrees clock & anti clock ways that seem to confuse the heck out me. So I graphed the events as illustrated in the tutorials you hot linked.

Intake:

Opening
.000â€￾ start of ramp 73* ATDC
.006â€￾ 53* ATDC
.050â€￾ 18* ATDC

Center line .321â€￾ @ 99*

Closing
.050â€￾ 213* BTDC
.006â€￾ 262* BTDC
.000â€￾ 281*

Valve open @ .006â€￾ for 315*

Exhaust:
Opening
.000â€￾ 291* ATDC
.006â€￾ 266* ATDC
.050â€￾ .231* ATDC

Center line .324â€￾ @ 113*

Closing
.050â€￾ 5* BTDC
.006â€￾ 48* BTDC
.000â€￾ 69* BTDC

Valve open @ .006â€￾ for 314*

Overlap @ .050â€￾ 23*
Overlap @ .006 101*

Center line separation 113* + 98* = 221*

Hot Lash Intake = 0.024â€￾
Hot Lash Exhaust = 0.026â€￾

[img]http://i294.photobucket.com/albums/mm87/wjajr/100_1378.jpg[/img]

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC