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GokuSSJ4
08-24-2007, 12:42 PM
http://forums.evolutionm.net/showthread.php?t=288337

good information:
this information was contributed by WOT (aby)


you can do all this with the cylinder head on, as long as your indicator has the reach to do so.

1. install the degree wheel onto the front of the crankshaft. situate the degree wheel in a way that is easy to read, basically 0 being in a readable position. tighten the fastening bolt down so the wheel doesnt spin.
2. make a wire pointer with a fine tip. be sure you can slip your belt on without having to move your pointer.
3. bring the piston to a visual tdc, adjust your point.
4. install your dial indicator on top of the piston, i put the indicator in line with the piston pin to help minimize piston rock. try & use a tip that has a ball on the end.
5. adjust your zero on the indicator, by spining the bottom end. once happy
6. i usually drop the piston ~.100", note the timing, swing it back the other way & drop the piston .100", note the timing.
7. add the 2, split the difference & adjust the pointer. for example. if you got 22deg & 16deg = 38 / 2 = 19. so if you stopped on 16 deg, did your math & now you tweak the pointer to 19 deg.

8. repeat steps 5-7 several times till your confident youve established tdc.

now your ready to put your belt & cylinder head on if you havent done it already.

i find it easier to place my indicator on the retainer top than having it rest on the cam.

then proceed with your steps of 7-9.

http://www.clubctrl.com/misc/one/degree_wheel.jpg


Originally Posted by turboDanÂ*
Does anybody use the Piston Stop method of finding True TDC or is it just us Motorcycle guys that use them?


by TedB
That is a perfectly good method of locating true TDC, and making sure your timing marks are correct.


by WOT
using a piston stop is fine, as long as you know what your doing / know where your @ when your aproaching your stopping device = dont want to damage the top of your piston inadvertantly.

my piston stop also incorporates a whistle to let you know when your getting close!



posted by crcain
Could you answer me one more question? Why on earth do the small degree numbers change from 120 to 50? What is the purpose of the small degree numbers?

Also, just for final confirmation, when you say 110in / 110 ex for cam figures. This always means 110 ex = 110 crankshaft degrees BTDC. And 110 in = 110 crankshaft degrees ATDC. Just double checking.



by Ted B
But there is far more than 360 deg of rotation associated with cam action. For ex, with cams of 280 deg duration and let's say 20 deg of overlap, that works out to 460 deg of events. Last I checked, you can't fit that onto a 360 wheel.Â*

"Exhaust Open BTDC" takes place at the end of the power stroke. The exhaust valves open just before the intake valve, not the other way around.

The small degree numbers are a matter of convenience when expressing IO, IC, EO, and EC values in their common context (e.g. BTDC, ABDC, etc.).

A 110 deg intake LC would be 110 deg ATDC. A 110 deg exhaust LC would be 110 deg BTDC.


Follow the wheel in this sequence:

TDC Power stroke - Exh Open - Exh LC - Int Open - Exh Closed - Int LC - Int Closed ,

Miss Evo8
08-24-2007, 01:02 PM
Are u trying to be Trinydex with the copy and paste?

GokuSSJ4
08-24-2007, 01:11 PM
i wish he would of done this kind of information when i needed it...Â* :crazy2: its ashame i hadnt read this or seen anyone discussing it

StockEVO
08-24-2007, 02:54 PM
Welcome to 1860! Wow imagine that. Someone actually using a degree wheel. :roll:

GokuSSJ4
08-24-2007, 04:40 PM
:roll:
this isn't anything new.. I'm well aware of that! I even had pics when they did my old 2.0l high compression set up back in my b series days...
but as it seems now n days with companies releasing longer duration and high lift cams, the need of degreeing cams seems to be a big part of an install for precise and accuracy; instead of trial and error.

ohhgyeahfasho
08-26-2007, 12:58 AM
that was a good read, very informational.. =)

trinydex
10-15-2007, 11:34 AM
i wish he would of done this kind of information when i needed it...Â* :crazy2: its ashame i hadnt read this or seen anyone discussing it
haha sorry i failed you goku... moral of the story is don't depend on an internet retard to provide you with crucial tuning information :]. God bless professionals like aby.