Abomination

Ok Ill check. Should I get a cleveland thermostat or use one of the pantera inserts if it turns out to be an issue>

Sure, hmm there are 4 bolts on the bottom of the valve cover. That means Cleveland right?

I wish that was the issue, but no they are going in the right direction. I think I might be onto something with the alternator, at idle it is showing 12v, so new fans and alternator and we shall see.

I just bought a 140 amp and new fans, when they get here I will try that. It kicks on the fans at 190, same as the thermostat, kicks. Both fans are on the same circut.

Here are some photos of the cooling system. I took a picture of the gap between the radiator and the radiator support, do you think that 1" gap can be causing an issue? Maybe I should try and seal it with a rubber seal of some sort?

I just bought two 2400 cfm fans based on that conversation, ill update when they are installed. I'm also doing a heavy coolant flush right now.

Head gaskets being blown can cause overheating, I checked it multiple ways and that is not it in this case. Timing is electronically controlled by the sniper. Actual temps are the same as the gauge as verfied by a flir temp gauge, mechanical gauge and cheap ir laser. Ill take some pictures today, thanks edit: just bought a new 140 amp alternator to try as well

Sure. It isn't boiling, the temp gauge has gotten to 235 before I shut it down. Verified with manual gauge and the coolant temp sensor on the fast efi, both match. I have replaced the radiator cap. I also put a vacuum pump on the coolant system incase there was a bubble It overheats all the time, but quicker with the ac on. Only at idle At idle it continually creeps up, never really hits a limit Its electronic timing, and yes it is verified. It doesn't detonate/ping that I can hear. I did hear some backfiring while slowing down under load yesterday I have both fans on at the same time I havent thought of the alternator, it is putting out 14 volts but didn't check amps. Ill look into it, thanks

Hmm... well I got this fan and radiator combo. It says 870 cfm each. They are hot wired with relays so are getting full power. Yes with the sheet of paper question, those fans put out some air. https://www.cjponyparts.com/radiator-4-row-aluminum-polished-24-type-379-big-block-mustang-1967-1970-with-air-conditioning-302-351-1970/p/RADA37/?utm_source=Pony&utm_medium=Email&utm_campaign=OrderConfirmation&lac_guid=737caf85-edf4-ec11-8368-0050568ba4b7 https://www.cjponyparts.com/dual-electric-fans-with-shroud-mustang/p/FAN18/

So, I have a 1970 mustang vert. Its a base with a stockish 351w with what sounds like, a mild carb. I put vintage air on it and sniper efi on it. Its tuned to be 13.5afr at idle (750rpm). So, car started overheating (vegas and A/C, so not unexpected) while idling. Looking at it I decided to replace my cooling system. I upgraded to a 4 core aluminum big block radiator with a great shroud and dual spal fans. I upgraded the water pump to a high flow aluminum pump. It still overheated. I did a prestone flush, cleaned out some brown water but no gunk. Refilled it, still overheated. Replaced coolant with distilled water and water wetter... still overheats. I did a block test, no head gasket. Oil is clean and fresh, no signs of a head gasket. Took a flir camera to it, no hot spots on engine. Radiator flows well and I can see it flowing. Thermostat is new, 190 degress. Verified working. Replaced radiator hoses with another flush, no collapsed coolant hoses. No coolant leaks. It will still overheat when idling. At speed it is fine. I'm at my wits end, hopefully someone has some advice or direction.

1970 base convertible. And thank you

So I already switched it and don't really want to do double work, it was a pain in the butt. Is there a brake switch that fits the curved arm? Searching the 69-70 brake switches look the same? Thanks in advance guys

Hey guys, really stuck. I swapped brake boosters and the old one has a symetrical circle for the pushrood, new one has a hockey stick shaped pushrod. It bolted up fine and looks identical and everything works great, only issue is the brake light switch wont fit on the hockey puck shaped pushrod. Does that booster have a different switch or am I being crazy? Pictures are just quick screenshots from the internet and not my brake boosters, but the pushrods look like these two