73 Q Code Cam Retarded 4 degrees?

[Don61]

I have read several older threads about the factory retarding of the cam on the 73 Q code engine for emissions. At the time, no one was able to say for sure if the retard was done with the grind of the cam or by the timing chain gear.

Does anyone on this forum know for sure?

I would like to advance the cam timing on my car and believe all that is needed is to install a new timing chain and gear set with a multi index sprocket set to advance the timing by 4 degrees. Is this correct?

Thanks for any and all advice.

 

[4Vforever]

This is something I'm not totally sure of either, but when my standard camshaft timing gear in my 73 Q code stripped and thus failed, I replaced it with a rollmaster (premium set) timing set and just set it up at on the standard dot to dot timing marks, after this change the engine came to life, especially down low and off the mark. Nothing else was changed performance wise and I kept the exact same tune in it that I gave it after I first purchased the car. To me I'd say that it is the timing gear that is retarded 4degrees, as if it were the camshaft it would've driven exactly the same as before the replacement of the timing set. Also this is what happened to later Clevelands (retarded timing sets) here in Australia, so I'd say Ford Australia just used the same design as these timing sets. The poor old Cleveland here in Australia, in its last form before being decommissioned only just made 200 HP, because of the retarded cam timing and choked up with pollution gear and we were still using leaded fuel here in 1982 also. Not a really great farewell to the once mighty Cleveland.

 

[TommyK]

I have read several older threads about the factory retarding of the cam on the 73 Q code engine for emissions. At the time, no one was able to say for sure if the retard was done with the grind of the cam or by the timing chain gear.

Does anyone on this forum know for sure?

I would like to advance the cam timing on my car and believe all that is needed is to install a new timing chain and gear set with a multi index sprocket set to advance the timing by 4 degrees. Is this correct?

Thanks for any and all advice.

I believe on the 73 351C the retard was in the cam not the timing set. If you use an aftermarket multi keyway timing set you can advance the stock cam but prepare to be underwhelmed with the effect of that small change. If you are going as far as changing the timing set I would strongly consider upgrading the cam and lifters. It isn't that much more work.

 

[RacerX]

Actually the retard is in the timing set. If you compare earlier sets to the 1973 set, you can see the difference side by side.

I installed a set specified for 1970 in my 73 Cleveland when we rebuilt the engine and it runs great. We checked everything with a degree wheel to make sure the centerline was correct and the open and closing were at the correct times.

 

[Don61]

Thanks for the replies so far. Two against one for retard in the gear assembly and not the cam.

I planned to drain and clean the cooling system and replace the water pump. Since the water pump will be removed it is not that much more work to remove the cover, damper, and replace the timing chain and gear assembly. At this time, I don't want to replace the cam and lifters.

Any additional information would be greatly appreciated. Thanks.

 

[IA Rider]

I agree with RacerX.

 

[RacerX]

If the gears are the same then why does every supplier have different part numbers specific to the 73 retarded cam timing and the straight up 70-72 cam timing gear? Pull both gears off the shelf and compare them. You'll see the timing difference in the cam gear for 1973.

 

[TommyK]

If the gears are the same then why does every supplier have different part numbers specific to the 73 retarded cam timing and the straight up 70-72 cam timing gear? Pull both gears off the shelf and compare them. You'll see the timing difference in the cam gear for 1973.

I most certainly could be wrong. I often am.

However my recollection is that the 351C 2V (and 400) was retarded at the sprocket as you say, but the 4V Cleveland that would have been in the Q code being discussed had the retard in the cam.

The aftermarket timing set makers are making one timing set for all 73 cams regardless of 2V or 4V. That does not mean that Ford did it that way.

In any event if the OP buys a multi keyway timing set as I stated in my first post, he can put the cam anywhere he wants with a degree wheel.

The point I was really trying to make in my first post was that expecting a night and day change from advancing a cam 4 dergrees will probably lead to disappointment for the amount of work involved.