Unleaded fuel in '71 429

Hello All!
I am looking at buying a '71 T-Bird with a 429... Is this an unleaded gas engine, or do I need to do the conversion?
Thanks!

If it were me, I would just drive the car on unleaded. If it starts to run poorly after a few thousand miles that means you burnt the valves. It costs the same to get hardened seats and valves installed whether or not the old ones were damaged. If the vavles don't burn, you just saved yourself the cost of having hardened seats installed.

You can buy that lead aditive at walmart that will make it last a lot longer. I have used it in my 73 tbird with a 460 that was rebuilt in 91 and not with hardened seats, and it is still running good in 2005.

Thanks for the replies, guys.. I'll wait till the fall to do anything with the heads. (I think the valve guides are leaking a little anyways) So I am assuming that in '71 the motor was build to run on leaded gas...
Thanks again..