Sled runs good till it warms up?

[vader]

I have a 1982 440 liquidfire. Ran good last year, would run around 110 degrees. I put invader heads on and am running 92 octane this year. I fire it up and it idles around 2200rpm, lights work everything is great. Ride around for a bit the temp climbs to about 150 degrees, that's when the gremlins come out. My idle drops to about 700rpm my lights dim lots. Probably because rpm drops. I still have power, rad is warm, and as soon as I give it gas lights come back on. If I hit my brake lights everything dims.
What are my heads toques to ?

[vader]

How can I cool it better? Is there a better heat exchanger or rad

[motoXman]

I don't think 150F is terrible. I believe that's about where your thermostat opens up.

[JDT]

Your idle speed might be to low. Try 3000 rpm's.

150 degress sounds normal.