[AZKen]

Thank you very much everybody. Keep the info coming. I have the original rad. Everything original. I can't figure 66 degree outside temp would cause this. I know that on straight 6 that the exhaust is right under the carb and the heat riser would be super efficient. I don't see how one manifold, on one side, could heat the manifold/carb very efficiently on a V6 or V8. That may be the answer...it doesn't work so well especially as ilvracn says, lots of iron to heat up. That's why the internal cooling passages are so robust. It's also a lot of iron to cool back down.
James, you say it takes 4-5 miles to reach temp on gauge. My questing is about how it runs in that 4-5 miles.
Maybe I will just have to keep using the choke until I install the heat riser. If that does not give results, I will start thinking other things....... Like what?
I tested my heat riser yesterday with a heat gun and it worked really well. Next time I test it, I will use my laser temp gun to see what temps it operates at.