64 Belvedere radiator core support

RHW2 · Apr 21, 2021

Has anyone swapped out the 22" core support for a 26" core support? If so details..... I can't seem to get my 64 to run under 210°. I've got a Griffin Radiator with the dual electric fans, a 180° thermostat, non hi-flo water pump. Details on the motor....440 .030 over, 11.2 :1, stroker crank 496 cid, full roller motor with a Crane cam. A & A Transmission cross ram intake with a pair of Edelbrock 650 cfm carbs. Set the carbs on a chassis dyno with A/F sensors. 4.10 Dana 60 with a Detroit locker, trans is a push button 727 rebuilt by Rick Allison at A & A Transmission, 3000 rpm stall 10" converter....516hp & 508tq at the tires. Even when cruising the temp won't stay down. It actually stays down longer when sitting still idling. On a mid 40° day the temp stayed down under 200° but as the outside temp goes up it runs hot. I've had other Mopars and never had this problem

diesel_lv · Apr 21, 2021

Where are your heating problems, at idle/slow speed, highway, or both?

RHW2 · Apr 21, 2021

No highway driving.... the problem is both but more rapid temp climb while moving

moparman400 · Apr 21, 2021

Try a Mr Gasket thermostat. I have had the same issues.......

RHW2 · Apr 21, 2021

I've used a couple different thermostats and no change. What makes you think it may be a thermostat issue?

dryheat · Apr 21, 2021

Fought a similar problem once a long long time ago. Finally I ran into an "old" guy and he told be to check the coolant for the presence of hydro carbons. Turns out I had a head bolt that was bottoming out in the block and allowed combustion gases into the coolant. It's a cheap test ....

RHW2 · Apr 21, 2021

dryheat said:
Fought a similar problem once a long long time ago. Finally I ran into an "old" guy and he told be to check the coolant for the presence of hydro carbons. Turns out I had a head bolt that was bottoming out in the block and allowed combustion gases into the coolant. It's a cheap test ....

Good advice... I'll check it out once I wake my Belvedere from hibernation

diesel_lv · Apr 21, 2021

I fought a cooling problem for about 6 months in my 496 w 26" aluminum radiator. But mine was at highway speeds. Aluminum shrouds actually created a high pressure zone and air would not get through the radiator. Went to mechanical fan and factory shroud and all is good. In the cooler weather, below 80°, I can't get the engine to 170° with a 180° t-stat. I use a Mr Gasket 180, flowcooler water pump and add 2 bottles of that pink radiator additive. In 100°+ days, it cruises down the interstate at 186 n in town at 195. Wish you luck.

RHW2 · Apr 21, 2021

diesel_lv said:
I fought a cooling problem for about 6 months in my 496 w 26" aluminum radiator. But mine was at highway speeds. Aluminum shrouds actually created a high pressure zone and air would not get through the radiator. Went to mechanical fan and factory shroud and all is good. In the cooler weather, below 80°, I can't get the engine to 170° with a 180° t-stat. I use a Mr Gasket 180, flowcooler water pump and add 2 bottles of that pink radiator additive. In 100°+ days, it cruises down the interstate at 186 n in town at 195. Wish you luck.

Thanks for your reply.... I wondered about whether the alum shroud/elec fans were causing an air flow problem. Now I have to try and find a shroud that will fit my Griffin Radiator. Then will put together a clutch fan set up

diesel_lv · Apr 21, 2021

RHW2 said:
Thanks for your reply.... I wondered about whether the alum shroud/elec fans were causing an air flow problem. Now I have to try and find a shroud that will fit my Griffin Radiator. Then will put together a clutch fan set up

I have a serpentine belt setup so no room for fan clutch and it's reverse rotation fan/pump. Used a 19" 11 blade nylon fan from a Chevy truck w a 496. Clears my 2 row radiator by about 1/2". It's a little bit of money, but this setup uses a single 17" that pulls a tone of air and a vacuum molded shroud. Let's air flow as it should. They fit the 22" radiators. I'm going to the dual 12" as it's shroud fits my 26" better and don't like my mechanical fan spinning so fast at interstate speeds, 80mph = 3,200-3,400 rpm.
http://coolingcomponentsinc.us.com/portal/store/products/category/17-series/

RHW2 · Apr 21, 2021

diesel_lv said:
I have a serpentine belt setup so no room for fan clutch and it's reverse rotation fan/pump. Used a 19" 11 blade nylon fan from a Chevy truck w a 496. Clears my 2 row radiator by about 1/2". It's a little bit of money, but this setup uses a single 17" that pulls a tone of air and a vacuum molded shroud. Let's air flow as it should. They fit the 22" radiators. I'm going to the dual 12" as it's shroud fits my 26" better and don't like my mechanical fan spinning so fast at interstate speeds, 80mph = 3,200-3,400 rpm.
http://coolingcomponentsinc.us.com/portal/store/products/category/17-series/

How did you get a 26" radiator to fit? Did you cut or swap out the core support?

diesel_lv · Apr 21, 2021

No, mine was original 26". Sorry I didn't clarify. I know there are 500+ inch motors staying cool on 22" radiators though.

SparkySDI · Apr 23, 2021

Are both your radiator hose connections on the passenger side? If so, you may only be cooling with a small portion of the radiator without enough cross flow.

JPrusinows · Apr 23, 2021

SparkySDI said:
Are both your radiator hose connections on the passenger side? If so, you may only be cooling with a small portion of the radiator without enough cross flow.

Change your lower pulley so it is bigger than your upper pulley and get a bigger belt. I’m running 650 to 700 horse on stock radiators and fans. It’s all in the pulleys. Your under-driving your water pump. It’s all in the pulleys.

c.moo · Apr 24, 2021

JPrusinows said:
Change your lower pulley so it is bigger than your upper pulley and get a bigger belt. I’m running 650 to 700 horse on stock radiators and fans. It’s all in the pulleys. Your under-driving your water pump. It’s all in the pulleys.

What is the size / measurement of your upper and lower pulleys ? Thanks

JPrusinows · Apr 25, 2021

I'll be working on the vehicles today and I'll get you those measurements. I had the same problem where someone put an aluminum lower pulley on to "gain horspower", LOL. Wouldn't stay cool pulley was way to small Same thing on my Hemi's the Race Hemi crank pulley was to small for street cruising, stop and go, etc. changed to larger Max Wedge Pulley and Bingo Bango all four of my rides never over 185 no matter the weather, etc. And I live in Mississippi with 95 degree 100% humidity days and stop and go traffic during cruising the coast. Here is a couple of old photos. Ill get you better measurements today.

JPrusinows · Apr 27, 2021

JPrusinows said:
I'll be working on the vehicles today and I'll get you those measurements. I had the same problem where someone put an aluminum lower pulley on to "gain horspower", LOL. Wouldn't stay cool pulley was way to small Same thing on my Hemi's the Race Hemi crank pulley was to small for street cruising, stop and go, etc. changed to larger Max Wedge Pulley and Bingo Bango all four of my rides never over 185 no matter the weather, etc. And I live in Mississippi with 95 degree 100% humidity days and stop and go traffic during cruising the coast. Here is a couple of old photos. Ill get you better measurements today.

View attachment 1102295 View attachment 1102302 View attachment 1102303 View attachment 1102304

Sorry for late update, don't know where my minds was. All 4 of my cars (2 Hemi, 2 Wedge) run the same combination of Max Wedge/Race Hemi Water Pump Pulley and Max Wedge Crank Pulley. All four run 180/185 tops. The smaller race hemi pulley ran about 230 and I would end up bringing it home and it was stumping me. Read a great article on pulley size and overheating, swapped the lower crank pulley and voila! Awesome feeling when it worked! LOl! Hope this helps!

dmoore · Apr 29, 2021

What are you running for coolant and what mixture ratio? I was having a similar issue with my stock 426-S 0.20 over, stock compression 10.3:1, factory fan & fan/clutch, factory steel shroud, 3 core Glen Ray. Last year I purchased Milidon's 160 degree high performance (bypass) T- stat and it ran a bit cooler during the hot months. Just last week I drained down ALL the antifreeze and went back with distilled water and a quart of Mac's (Napa) rust inhibitor/water pump lubricant only...this made a very noticeable diff as well. Infrared gun on thermostat housing now shows 175-178 on 80 degree day. However it's still Spring here in Va...The real test will be in the coming months.

dmoore · Apr 29, 2021

SparkySDI said:
Are both your radiator hose connections on the passenger side? If so, you may only be cooling with a small portion of the radiator without enough cross flow.

Doesn't appear to be

dmoore · Apr 29, 2021

RHW2 said:
Has anyone swapped out the 22" core support for a 26" core support? If so details..... I can't seem to get my 64 to run under 210°. I've got a Griffin Radiator with the dual electric fans, a 180° thermostat, non hi-flo water pump. Details on the motor....440 .030 over, 11.2 :1, stroker crank 496 cid, full roller motor with a Crane cam. A & A Transmission cross ram intake with a pair of Edelbrock 650 cfm carbs. Set the carbs on a chassis dyno with A/F sensors. 4.10 Dana 60 with a Detroit locker, trans is a push button 727 rebuilt by Rick Allison at A & A Transmission, 3000 rpm stall 10" converter....516hp & 508tq at the tires. Even when cruising the temp won't stay down. It actually stays down longer when sitting still idling. On a mid 40° day the temp stayed down under 200° but as the outside temp goes up it runs hot. I've had other Mopars and never had this problem

View attachment 1100726 View attachment 1100727 View attachment 1100728

That 4.10 isn't helping your cooling issue at highway speeds I wouldn't imagine??

64 Belvedere radiator core support

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