rear gear change advice

[Tommy]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ssl78</div><div class="ubbcode-body">when its at 200 did you ever take a infra red gun and take a reading going into the radiator and out of the radiator to see the temp drop </div></div>

I was going to ask the same thing. Those little heat guns are cheap and work great. I think they are still around 20 bucks at Harbor Freight. I check my header tubes, radiator, t-stat housing on my stuff with them. I agree with the Masses, it shouldn't be the gears. I ran 3:73's up and down the interstate for hours at a time without issue. I also don't think 200-205 is hot either... If your fan is flattening out at the higher RPM is won't push as much air as did before. I have experienced that with flex fans and tall gears. They would run cool around town but flatten out while flying up the interstate and my temps were higher then. Still, 200 isn't bad in my opinion. I do have large box fans in the garage that I run in front of the car with the hood open after hard drives. That's only because I don't like to watch the temps skyrocket after shutting off these old engines. I worry about cooking the bearings sometimes Hope I helped some.


Tommy [img]<<GRAEMLIN_URL>>/[/img]

[JOZW30]

I have messed around with the IR gun. I was using it to look for any crazy hot spots but everything seems pretty symmetrical heat wise. If I remember correctly the temps were lower on the lower hose by about 10-15 degrees.

I just pulled the car out of the car jacket Sunday so I still need to tune and change fluids, so no big deal to drain radiator and try to pull some of the block plugs to see what kind of mess I end up with. I keep thinking it's a flow problem.

Anyone ever done this before?

Plowman, I need to pick up a coolant gauge but I shoot for 50/50. I didn't know too much antifreeze would cause a car to run hotter. Can adjust that when I refill from trying the block plugs. I only drive the car in Ohio summer (hopefully soon AZ, so I better get his fixed!), so what is a good mix/ratio to shoot for? If I pick up a coolant gauge what temp is best?

I do like the 3.73's............

Appreciate the input.

[JOZW30]

Thanks Tommy,

I have stock pulley's and fan with clutch.

Joe

[69SSZL1]

200 degrees is not bad. Try Redline Water Wetter in your radiator. It WILL lower your running temp. Make sure your radiator is not partially clogged with rust or debris. You may not be able to remove your block plugs, they are usualy stuck from age. Good luck!

[PxTx]

I would have expected more than 15 degrees difference between the upper hose and lower hose. I would focus on why that is and hold off on looking at the block. I think you are on to it with the clutch fan being loose after a shut down heat soak.

Friends in California run straight water for better heat transfer. You should run something like the water wetter or other conditioner to help the bearings in the water pump and keep the rust down. Antifreeze is just for that. You could run water in the summer and drain half of it and add Antifreeze in the fall.

There is also a great debate on the benefits of Evans Coolant, but I don't want to muddy the waters in this thread.

[JOZW30]

I'll try to the water with the water wetter (think you need the anti--corrosion stuff at least). and I think I'm gonna just get a new fan clutch and see what that does. Easy to do and not that expensive maybe I got a bad one last time.

[69SSZL1]

I use the Water Wetter added to 50/50 antifreeze/ water

[Kurt S]

All kinds of lubricants and anti-corrosion additives in coolants. I wouldn't run water. Coolant isn't the problem.
I'd make sure the water pump is good. 'Performance' in the description of a w/p isn't something I look for - often that means they've messed with the vane design.
Take a look at John's article - http://www.camaros.org/pdf/corv_cooling2.pdf

[budnate]

I had one kinda like this once finally figured out the custom stainless blades had lost there oomph at speed they went flat and was not moving air...your conditions sound just like mine did then, zero in on your fan and the clutch, you might install a new solid fan for a test.

[kwhizz]

Hummm!!!.......I would take that &quot;Performance&quot; Aluminum pump off and put a stock GM pump back on and see what happens........Performance = Chinese........