Synthetic oil or not?

I am about due for an oil change on my 70 Road Runner with 440-6. What recommendations do you have for moving to a synthetic oil? good idea or not? TIA

You want something with high zinc.

https://lucasoil.com/products/hot-rod-high-performance/hot-rod-classic-car-10w-40-motor-oil

http://www.amsoil.com/shop/by-product/motor-oil/gasoline/z-rod-10w-30-synthetic-motor-oil/

Depends on usage. Synthetic may be an advantage or just an extra cost.
Also there are several base stocks that can be called "synthetic". There were some problems with early synthetics made entirely from one of the base stocks. Shouldn't be a problem with any reputable synthetic today.

Brad Penn.

Brad penn

Use Brad Penn, it is semi-synthetic and has higher Zinc content for flat tappet cams.

Synthetic lasts longer between oil changes....if you are a "maintenance super hero", there's no need for it. I pulled apart my original Mustang motor after 250,000 miles, running only the cheapest conventional oil (using police/severe duty maintenance schedule) and it looked like you could eat off of it...no sludge whatsoever. High zinc (as found in high mileage oils) is a good idea for cars without catalytic converters.