Getting better!

I'll read everyone's replies and respond later. It's not fixed, but we're moving!

Thanks everyone for the ideas!

"One thing I did notice is one of the exhaust cross overs seems to have burned out and burning the paint on the intake. I wouldn't think that would cause the issue, but maybe?"

That is a natural occurrence. You didn't use the truck intake gaskets to block some of that crossover exhaust heat (well duh! you have headers - no crossover provision)?  There is also a tube in that intake crossover that if corrodes will allow exhaust gases to escape out of the tube inlet/outlet ports under the carb flange. 

Anyways, you are doing one heck of a job getting it across the Rockies.

BTW - Does the wife smile when she hears the turbo?     

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#1. Lower hose does have the spring. Verified yesterday during the water pump change. I'll give them both a squeeze again to double check.

#2. Yes we kept the pump but I have no intention of rebuilding it. We have changed over the car pump and smaller 68 Mustang pulley.

3. The intercooler. This could be an issue, but it's heating up before we start making boost and IATs aren't much above ambient.

4. Smaller car pulley. Which helped for sure.

Our temp sensor is mounted right next to the thermostat on the front top of the intake.

One thing I did notice is one of the exhaust cross overs seems to have burned out and burning the paint on the intake. I wouldn't think that would cause the issue, but maybe?

That's why we were at Lowe's yesterday! We have an igloo cooler we are getting set up on the headache rack to gravity feed water to a spray bar

We tried the zip tie mounts and that was the main reason for our detour to Summit. The fan without the shroud couldn't keep up in any condition.

The fan in the shroud on our particular application has been better in every phase. It's hard to see, but there is louvers in the corner to allow some air to pass at speed. I don't care for this design and would much rather have the rubber flap design, but we don't have a way to do this on the road.

Thermostat is a brand new #304 Robert Shaw 160° and working much better that the standard flow we had in when we left.

Do do have the stock fan and shroud but I'm not sure we have a way to put it all back on without fab work.

1) 10-4 on the lower hose collapsing @ speed. It has to have a SS spring inserted

2) You kept the take-off pump to be rebuilt?

3) While I was looking at your build photos and drooling all over the place, it did not dawn on me how large the inter-cooler is. It almost blocks the radiator core and may be a reason it overheats @ speed.

4) Did you keep the original WP pulley or go to a car style? It may be that the pulley dia is not moving coolant quickly enough. With the rad cap off and looking into the top tank, is coolant moving after thermostat opens? This is a problem on the 55/57 BIRDS.

5) What is the rear ratio? It may be winding the engine too high for today's roads/speeds. Is the trans a direct or OD in final gear?

6) And I never figured this one out. The TEMP SENSOR is on the left driver's cyl head and actually measures coolant temp coming off the cylinder barrels left bank. The temp may vary greatly between there and the thermostat.

7) The wife seems to be in good spirits but maybe block off the heater core so she doesn't get too hot?



Possibly, if there is a large air gap between the rad and inter-cooler, the air-flow is disrupted.

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With shopping if you come across a 12v pump like a windshield washer and tank  and plumb it to a copper tube in front of the radiator with about 10-12 small holes drilled in it. You can switch it on when needed to squire down infront of the radiator. I had to do that on an 60’s pickup with a camper when I towed on hills. Good luck. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

I would try removing the shroud.  Most OEM shrouds are contoured to funnel air through the fan or the fan is so large that it is nearly equal in size to the core area, leaving the core largely unobstructed.  And they don't usually have a large intercooler in front of them.  At present, the radiator has a significant obstruction in the front and in the back.

There are "zip tie" style mounting "brackets" you can use to mount the fan directly to the core, https://www.summitracing.com/search/part-type/electric-fan-mounting-brackets-hardware?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=fan+mount  If you have tools, you can make brackets.  A mechanical fan can also be used.  You can remove the fan and shroud on the side of a highway, to test it on an open road.  Neither the fan nor shroud is needed at typical highway speeds.

I've had a thermostat that didn't open completely.  At low speed it cooled fine but above about 50, the temp climbed rapidly.



Lawrenceville, GA

How is your lower radiator hose ? A soft hose maybe collapsing at the higher RPM. More water then coolant is better. I usually use 60-70 % distilled water. Where exactly are you?

Yes the temp reading is verified correct.

The #304 thermostat is a 160°. We can get to 145° pouring cold water over the radiator with it idling. We only did this once to get it cold enough to safely pull the radiator cap for testing.

From a cold start it will get to about 163° and cycle back to the fan shut off at 155°.

We just checked back into the same motel as last night. Everything we have done has made a dramatic difference. But it still wants to creep at 50mph with any hint of a hill. The good thing is today when it got to 210° we could pull off the road and it will start cooling down on it's own, yesterday it would continue to climb.

We have played with the AFR and timing going down the road and have it set at the coolest settings for our particular combination. We went back to premium gas today and no difference. FWIW ethanol free is 100° hotter in EGT vs E10 of the same octane.

We've decided to wrap the headers and down pipe after we go split a $17.99 Steak and Lobster at the casino.

If that doesn't cure it, we have a igloo cooler that holds 5 gallons of ice water, it'll get a bulkhead fitting, ball valve and tubing to the front of the radiator for corrective cooling while moving.

We also have the old heater box complete with heater core and fan we can plumb/wire and run to help out.

We have the original brass radiator with us, but the top tank has a leak. If we refit that it would take some reengineering of the fan situation as well.