Degreeing Cam / Offset Keys available?

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360duster

360duster

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Hi Guys, i wonder where the Offset cam keys are available? I´m installling a new cam in my 408, can not get it right with the Adjustments that can be done with the Timing set. P4286500 seems to be discontinued everywhere…..Thanks!

Michael
 
The offset keys are obsolete... FCA has discontinued many parts after 2010....

Some timing chain sets let you go +/- 4°...
 
I noticed that also. I was looking around for them and noone had them. The only thing i could find was like offset bushings. I dont even know how that would work. Best bet would be to get the timing gear with the different slots that is what im doing.
 
The offset keys were used on small blocks and the offset bushings were used on the big blocks.
 
Part # 987G is 2 degree, 988G is 4 degree. Several on ebay, but like everything, the price has gone up.
 
Cam should be installed at 106 icl, with the 0-position of the crank sprocket i get 107 - 108°, with the 2° advanced Position of the crank sprocket i get around 104° icl…….would like to have it more precise, not knowing if it really matters this much.

A guy over here in Germany found a P4286500 kit in his stock, bought it.....i think with the 1° Offset key it will be ok.

Thanks guys!

Michael
 
If it was me, I would just put it in at 104. The chain and sprockets will wear over time and retard the cam.
 
For those that mentioned using the SB Chevy crank key keep this in mind, when using it your also moving the position of the harmonic balancer so the balancer timing marks will now be off (assuming they were accurate before)
 
fishy68 said:
For those that mentioned using the SB Chevy crank key keep this in mind, when using it your also moving the position of the harmonic balancer so the balancer timing marks will now be off (assuming they were accurate before)
Click to expand...

No, the sbc crank key fits in the sbm camshaft.
 
And the 2 degree key value for the SBC crank key when used in a SBM cam application now has a 1 degree of change value, when used on the cam/gear !
 
360duster said:
That´s good to know! These are available trough summit etc. The 2° Key will alter the cam Timing 1°, the 4°key will alter the cam Timing 2° if i understand correctly.
Click to expand...
I do believe this is backwards...... If the key moves the cam 2 actual degrees, then this equals 4 degrees movement at the crank.
Cam timing is measured in crank degrees, so 2 degrees of actual cam change is 4 degree of cam timing change.
 
This Chevy key idea does not sound to me like it will make fine cam timing changes, unless you can find a 1 degree key. And even then that sounds like a problem, as the cam snout diameter is smaller than the crank snout. A given physical offset will produce an increased number of degrees change at the cam sprocket, meaning even more degrees of change at the crank.

If anyone has the actual offset dimension of either of these keys, then the actual timing change can be figured out.
 
Max1196 said:
And the 2 degree key value for the SBC crank key when used in a SBM cam application now has a 1 degree of change value, when used on the cam/gear !
Click to expand...

So the chevy crank key is the same as the mopar cam key, how small is the chevy cam key???? :rolleyes:
 
I have used the Mr Gasket Chevy crank key for an offset cam key in a 340. When I degreed the cam, IIRC the 2 degree Chevy crank key gave me 4 degrees advance.
 
360duster said:
Cam should be installed at 106 icl, with the 0-position of the crank sprocket i get 107 - 108°, with the 2° advanced Position of the crank sprocket i get around 104° icl…….would like to have it more precise, not knowing if it really matters this much.

A guy over here in Germany found a P4286500 kit in his stock, bought it.....i think with the 1° Offset key it will be ok.

Thanks guys!

Michael
Click to expand...

It doesn't matter that much... Unless you used a super-high-quality timing chain and sprockets, your cam timing will retard 1-2 degrees regardless after a few hundred miles of running since the timing chain ALWAYS stretches. So put it in at 104 and over time it will gradually work itself up to 105, mayyybe 106, not that you'd ever notice a difference anyway in how it runs.

Also 1-2 degrees is so small you could be getting that much difference just from user error and small variations in the measuring tools (degree wheel, pointer, etc.). For me personally I repeat at least 2 full measurements with the degree wheel of the cam phasing and as long as it's not off by more than 2 degrees and I get the same results each time, I call it good.
 
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