timing the p-7100 (timing chart)

[DTanklage]

this is one of the charts that was created (modified) for timing the p-7100

the reason it was modified is because the cummins dealer could care less how much plunger lift there is with 30° timing but high perf enthusiasts do



it is not 100% accurate because there are other factors that determine timing other than the plunger lift. because of this most shops dont even use a chart. they use a simple formula:

3.2/1.7/2.4 (160/180/215) .1mm=.5°

desired timing divided by five plus the contant equals lift @ tdc. say you have a 160 pump and desire 15° of timing. 15/5=3+3.2=6.2mm

to time the engine you need to get tdc marked on your balancer. there are various ways of doing this i prefer using a dial indicator and a degree wheel. that is easy with the cyl head removed a little trickier with it in place. there is also a valve drop method a valve spring compressor method and if all else fails there is a timing pin on the back side of the front cover. once tdc is accurately marked you can use a dial indicator in a special holder that replaces the #1 dv holder to figure out approx where the pump is timed. i say approx cuz as stated there are other factors that determin exact timing

what the timing tools are measuring is where the pump shaft is in relation to the crankshaft or better yet how far up the pump cam the number #1 plunger is in relation to the crankshaft. checking plunger lift is just a starting point cuz we want to know where the number 1 piston is in relation to top dead center when the #1 injector 'pops'. and the only way to find that number is with a timing light

i use a snap-on sp500 timing kit to get a reference point and then a mt257b pulse adpapter and a mt1261a digital timing light to find at what degree the injector is popping at that reference point

if 6.2mm of lift ends up being 18° on the light you know to subract six tenths of a mm from the reference point cuz every tenth of lift equals .5 degrees

6.2 - .6 = 5.6

set it at 5.6 lift set the light to 15° fire it up and your lines should be lined up


don


*one thing to note is that when timing a 215 pump always back the motor down til the #1 plunger is on the heal of the cam (no lift) before poppin the gear lose. while it does not matter where the plunger is on the other pumps the pump will try to back itself up when you break the gear loose on the 215

[colin91]

definitely needs to be a sticky!!!

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1996 2500 ECLB, NV4500, 4x4, 4" redneck tb exhaust-5" tip, BD brake, ATS 3pc, #0 plate, 4K GSK, wastegate plugged, SouthBend, welded 5th gear, Isspro pyro&boost, leveled, Thuren track bar, AFC tweaked, BHAF, silencer ring?, 15%/5% tint, 285/75/16 MT ATZ

[12vbigkermit]

x^2 on that one great right up

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98 2500 4x4 7"38's, 8kh.i.d, pump tweaks, 4gsk, stacks, inline defuser,FASS,gauges,Suncoast billet trans bllt flex plate, tc lck up, timing, k&n, head oringed+ stg3 valve job,60lbs spring,coaltrain 140's soon to be a1's and super b special.

[DTanklage]

thanks

dont forget the thanks button

(i am in a race with tony)

lol