Ultravan #520 and I arrived home safe and I like to think all who helped.

[BA-in-Mich]

Seen one setting a few miles from my house.

[UV Owners]

This is some of what has been done over the years to try to resolve the overheating issue.

Computational Fluid Dynamic model...
This is what they use to do wind tunnel test in a much smaller scale.


So far to date (over the years of classes) they have tested:

1. Over the coach
2. Under the coach
3. Around the coach
4. The engine compartment
5. Different style spoilers to direct the air over and down the back
More test still to come and on going...

[Daveinet]

For some reason, I thought the rear of the Ultravan began slanting downward sooner than the model in your photo. The rear of that model looks too vertical.

[Daveinet]

On more comment. I went back and reread the thread, seeing your post about overheating. I have seen where the secondaries on the 4 barrel did not want to flow fuel, which caused it to run lean and overheat. I don't remember the real cause, but once the carb got straightened out, the overheating issue went away. Because the secondaries are vacuum, running lean does not seem to make it misfire. It just doesn't gain RPM, so you don't get as much flow and the secondaries don't suck open as far.

[UV Owners]

Originally Posted by Daveinet

On more comment. I went back and reread the thread, seeing your post about overheating. I have seen where the secondaries on the 4 barrel did not want to flow fuel, which caused it to run lean and overheat. I don't remember the real cause, but once the carb got straightened out, the overheating issue went away. Because the secondaries are vacuum, running lean does not seem to make it misfire. It just doesn't gain RPM, so you don't get as much flow and the secondaries don't suck open as far.

Thank you Dave.
I don't think that is the cause. But I can look into to it to be sure.

I have a lot of upgrades planned for it, as soon as the snow is gone and the weather is nice enough to work outside.

Tony