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Is the timing on counter rotating engines , twin chevy inboards 305 merc. 1982

The value will be the same....if it has the correct timing tab on it (B and A get reversed on the RH engine' timin tab-from the LH egnine's tab) you can read it directly. IF not, you're better off getting 'advance' style timing light and just using the TDC line on the tab.
 
On reverse rotation engines, the cam and distributor drive gears are reverse cut. Even tho the engine spins backwards, the distributor spins in the normal way. The starter drive gear also.
 
actually, on the gear driven camshafts, on the RH engines, the distributor gear is the same cut as on the LH engines.....otherwise, you'd need a different distributor. the gear drive on the camshaft makes it's rotation the same as on a LH engine...
 
makomark said:
actually, on the gear driven camshafts, on the RH engines, the distributor gear is the same cut as on the LH engines.....otherwise, you'd need a different distributor. the gear drive on the camshaft makes it's rotation the same as on a LH engine...
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Yes...... that is correct!
To my knowledge, no one has ever designed an opposite rotation SBC oil pump, therefor the distributor must rotate same as a Standard LH Rotation Engine.

However, and I'll pose this as a question.......... I'm thinking that in 1982, the SBC RH Rotation Engine's camshaft was chain/sprocket driven...... yes/no?????


But I digress back to the timing question:
Yes, the timing specs between the Std LH Rotation SBC and the REV RH Rotation SBC will be the same.

I would strongly suggest that you find True TDC using the PPS procedure.
I would then suggest that you mark off each harmonic balancer up to approx 35 degrees.
(these markings will be opposite each other)

Now you can check the Progressive and Total ignition advance using a std strobe style timing light, and you will be able to read Real Degrees in Real Time!


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