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Building "Nightmare" (78 GMC Jimmy)

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Shit! 30 min burn on the freeway and I hit 223 turned off the ac and got off the freeway and got it back down to 210.
It's like my problem just reversed.... now I overheat on the freeway but I'm good in the city wtf.

My friend suggested I go back to mechanical and do a heavy fan clutch and a 160 thermostat with a small opening and a 1" fan spacer to get the fan closer to the radiator. Guys I'm stuck a d running out of time. What do you think?
 
How many running ac and a built big block?
I'll start with the cleaning and see
 
If you have enclosed the whole radiator so that it has to go through the fans after going through the radiator, that that is your issue on the freeway. The fans are going to block the air trying to get through the radiator at freeway speed.
Granted mine does not have A/C it does have a oil cooler and trans cooler when I ran it up to Eric's house in ID in the 50 degree weather it did not even open the thermostat let alone need the fans turned on.
In Moab, my big fan is on a controller that turns it on low speed at 185 green light, then red light high at 210, it hardly ever goes red and turns on full speed. My smaller fan is on a switch that I will turn on not very frequently.

I just have the fans mounted with their factory shroud about an inch or so away from my radiator. No additions to the top or bottom or sides.
My engine is relatively stock.
 
Ok yes mine is almost completely sealed around the radiator. I can likely push it back an inch or cut the sides off.

I think you and I are on the same page lol. I'll take a pic and show you.
I assumed I wanted it as air tight as possible so air had to suck past the radiator
 
Weird, maybe I'll add a 1/2 gap and see if it helps, for now I pulled the radiator and will get that done tomorrow.

I also swapped our my thermostat I did what the race car drivers do. I went to a 160 thermostat with a smaller opening. It will cool sooner and slow it down enough to actually cool in the radiator.


20170828_212534.jpg
 
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bent72 said:
Take the top off. No AC, problem solved
Click to expand...
The pregnant lady does not approve of that idea lol plus that still leaves the condenser up front ;)

ok guys i will be the first to admit when i am wrong....
I may have been wrong...
the radiator guys have it torn down, they told me i do have "the big big 454 radiator" and its the "high eficency one" ( he said never throw it away someone would buy it and its easy to repair) here is where i was wrong,

i thought the fans sucked, turns out my radiator was at least 15% plugged, also it had some small holes that i thought were my overflow leaking, just pin holes but he said it wasnt helping with propper pressure.

Will this fix my problem? I dont know.... will it help? hell yes it will help.

I also discovered i had a 195 thermostat and not a 180 like i thought.. I'm debating pulling the 160 and going with a low flow 180.. or sticking with the low flow 160 and seeing what it does. if i could get this sucker to run 180-190 i will be so thrilled.

Should i add a gap between my fan shroud and the radiator or should i slap it back together how it was and see what happens?
 
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You get moar air the faster you go. Never rode in that Saturn with nitrous, I'll confirm you had a bottle.
 
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