Crankshaft degree wheel for cam timing

weeJohn

weeJohn

Lifer
I found this, its a printable degree wheel jpeg for crankshaft position. It would need to be cut out and mounted onto a piece of stiff card or plastic, it may not be as accurate as a cam manufacturer supplied one but it would do for a guide to check things are close.

degreewheel.jpg
 
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Skalabala

Member +
Hmmm :)
By looking at this can I say that there will be no piston to valve contact even if there were no valve relief on piston?
Piston already starts to go down as the intake valve opens?
 
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Skalabala

Member +
Had a look at my engine timing today, and it looks to me that intake valve lobe starts to open the valves at around 10 ATDC!
Am I mad?
This was for the piston closest to the cam belt.
 
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AdamB

Member +
It should be BTDC, your miles out. I thought the intake valve will normally open around the 25deg BTDC mark.
 
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Skalabala

Member +
But if ignition timing is 10BTDC how could the valves open at around 25 BTDC?
Would make an explosion into the intake manifold?
 
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AdamB

Member +
A full 4 stroke cycle is 720deg of crankshaft revolution don't forget. The 10BTDC is base timing only.
All cam specs/valves i've looked at open at BTDC.
 
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Skalabala

Member +
I am going mad :D
This is how I put the cams in.
DSCF2580.jpg

DSCF2579.jpg

DSCF2582.jpg


As far as I know it is not possible to put the cam timing wrong in a 4E because of the clear markings it has.
The 10 on the bottom cam belt cover is 10BTDC right? And 10ATDC will be a emagination of 10 after the 0?
 
sx_turbo

sx_turbo

Lifer
skala bala what you have done is correct,

now at the end of the exhaust cam is more marks for the distributor, this is for the ignition timing and is already set to 10 btdc, once all that is lined up there should be no need to further adjust the distributor, the ecu should and will do the rest
 
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Skalabala

Member +
Thanks bud, but this engine is not in my car yet, this is the new rebuild donor. Going to use a stand alone btw.
And the cam timing is screwing my brain as explained... :(
Piston 1 intake valves will start to open at around 10ATDC, what is wrong? This does not sound right :(
 
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AdamB

Member +
Your right,it doesn't sound right.
I have a spec sheet here for cams for the 4EFTE engine from Tighe cams. The only camshafts they list with the valves opening ATDC are ones with very little duration, ie 82deg, 147deg.
 
weeJohn

weeJohn

Lifer
Skalabala said:
DSCF2580.jpg
Click to expand...

I dont trust this mark, there is a mark on the timing belt crank pulley that has a reference on the oil pump body, use that. Intake valve should be opening 2 degrees BTDC and closes 42 degrees ABDC. As for the explosion in the intake, it would need to fire the spark plug for that to happen and this is the intake stroke you are talking about, not the power stroke.

Was the distributor rotor arm pointing towards lead number one when you started to check cylinder 1?
 
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Skalabala

Member +
There is not a dizzy on the engine.
Could I have put something wrong? Or maybe made a stupid mistake when I looked at where the cam starts to open piston 1 intake valves?
I will double check this later this week :)
 
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Skalabala

Member +
Yes what Adam said. If you look at all my timing marks could there be anything else wrong?
I did double check the accuracy of the pulley mark John buddy.
The posted degree wheel is not for a 4EFTE is it?
 
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AdamB

Member +
No the posted degree wheel is a general timing wheel :)
You can easily make your own if you've got a piece of card and a protractor lol.
 
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