Big block running hot. Can’t figure out the issue

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legopnuematic

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Adding to the discussion maybe it will help although I’m not well read on reg vs reverse rotation, but I have a Gen VI 454 bone stock in the 86. But it has old fashioned v belt system. Presuming the water pump was swapped for a v belt pump when the engine went in.
So do they cool the same reg or reverse rotation? I’d think so. IE it doesn’t matter which way you push the coolant through the engine.
But reverse cools the heads quicker (aka the 90s lt1 engines, early aluminum head 350s).
Not sure if this helps w your issue or just rambling.
The reverse rotation/standard rotation pump thing is just the impeller mirrored as the serpentine setup spins the pump the opposite direction that a v belt setup (or flat belt setup that uses the grooved side of the belt) does.

The flow path to and from the radiator remains the same for either pump setup.

Photo is of two ford pumps (their open design makes it a good visual) one std and one rev rotation:
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nvrenuf

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I'm glad the radiator turned out to be a big one, that should cool fine.

For the record, the 049 and 781 heads are basically the same casting so (if they are good) swapping between the 2 castings wouldn't make any difference.
 

Slooptin

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I'm glad the radiator turned out to be a big one, that should cool fine.

For the record, the 049 and 781 heads are basically the same casting so (if they are good) swapping between the 2 castings wouldn't make any difference.
Sorry, meant 045 heads. I have another set of 049 cores sitting in my garage waiting to get some love.
 

Ajax19

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I dont think it was boiling over. sensor was in the head prior to me refreshing the motor, but i switched from 049 casting heads to 781 heads. I figured the heads would be hotter, but it sat at right under 210 before this with the sensor there.

And, it's still standard bore. only thing that changed internally were new pistons, rings, and rod bearings. I used cast iron rings so I assumed those would get hot while the rings were getting seated but its been probably 100+ miles now so i assumed the rings should be seated by now. Fan clutch is a new HD clutch and it definitely moves air
Fershure man the new rad will probably help out heres the cheap equis gauge on mine reads 230 normally but will go up to 245° when I'm doing a long up hill (there's a 50mile uphill grade where I live have to go up when I go visit my mom in the boonies) hopefully you get it where you like but like I said engine is probably ok as long as your not boiling over
 

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