The spark timing is referenced off the crank. The distibuter doesnt care where the cams at, 2/4/6/8* advanced or retarded.

A good example is pull the distributer out and spin its gear around anywhere you want and stick it back in. The only thing you will change is the position on the cap of the new # 1 cylinder.

Of course you will now need to fine tune the timing advance in reference to the crank.

Now, a cam being retarded will have a later IV close so it may want some more initial timing advance. But not 30* IMO

Its something else thats requiring that much advance to run smoothly. Are you using a adjustible timing light? Wire order correct,? ETC