I have been chasing a heat spike issue with my 85 Z28. After replacing the 195 thermostat with a 160 the problem diminished, but not gone all way. I then decided to replace the clutch fan and did. However, when I raised the hood I found this!!!!

 

That'll do it lol

 

Yes Sir I am very disappointed in my 32 year old upper radiator hose!!!! Lmao

 

WOW. I have seen the lower hoses do that, never the upper.
That picture is proof.

 

Wow, that's pretty bad for flow, isn't it.

 

You should replace the 32 year old radiator cap, if you haven't already.

 

Yes Sir I am going to be replacing the radiator cap as well.

 

The Camaro now has a new water pump, lower radiator hose (previous owner),thermostat 165 with 3/16th's vent hole, upper radiator hose, clutch fan, radiator cap, and fresh antifreeze. Now we'll see if she creeps up to 220 in the South Texas heat.

 

Whipped it!!! After 30 minutes of highway and city driving to include 4 miles at 85.

 

Excellent!

 

Thanks. My next step was a new aluminum radiator.

 

Good job John, stay cool, mighty warm down here!

 

Thank you Sir!! It was 105 yesterday!!