It seems that you can not run 440 water pump pulley on a 426 street hemi and not overheat at idle. The ratio will not turn the water pump pulley fast enough. Lessons learned after spending bucket loads of money on new housing ,high flow water pump, high flow thermostat, 3 row 26 radiator and the list goes on.

A big block non a/c pulley fits and works but the stock diameter of 6 13/16 is two large. Yes I am running a thin 440 style damper with all of the correct 440 (big block brackets) Does anyone sell or have a part number for a smaller diameter pulley?

I wonder what diameter crank pulley? 7"-7 1/4" range is common for OE.

In general, Bouchillon has been helpful for me with pulleys, knows MOPARs and sells a bunch. I would give them a call.

FWIW My BB runs a ~5" fan/WP pulley from Bouchillon. It is a "with AC" setup.

https://www.bouchillonperformance.com/

Diameter is about 6 1/2 for groove 1(water pump and alternator drive groove. I have the same setup on a 440 with no problems, the difference is the hemi runs a lot hotter and needs more cooling.

what dia/depth do you need?

The big block non ac water pump pulley would work, its OVERALL depth is 2 11/16 but the Pulley Diameter is 6 13/16 way to big .. I need the same depth but with a 5.5 or so diameter.

Tell us about your radiator, and fan combo.

Gimme a couple of days

stock water pump housing (replaced 440 source problem one) high flow water pump (replaced 440 source junk) high flow thermostat at 180 7 blade fan and new clutch with 3 core 26 inch us radiator all timing correct

Looking back at your post history, you been having overheating issues for a decade now.

What are you calling overheating?

You are correct, when I started to work on this problem I had the 440 source junk parts on my car. The housing was restricted and the the water pump was junk. The car would overheat in the summer within 4-5 minutes at idle and temp would spike over 220 and still go up. I removed the crap parts from all my big blocks and it solved the problem except for my street hemi. Now the car would take 10-15 minutes and still over heat. Problem halfway fixed but still a problem. So I replaced all hoses and belts, put in a $30 high flow thermostat, (never paid that much for one in my life) new cap, adjusted timing and carb and still over heats. I put on the new hayden heavy duty clutch fan with seven blade fan and still overheats at idle. Was told my radiator was one of the best on the market (US Radiator) 3 core with shroud that is sealed. and still overheats.I also added the heater core and removed the bypass hose I had at the pump. Nothing helped. So I removed the cap and notice no water movement at idle.Go figure, when I hit the gas I noticed water movement like a rushing river. My friend told me about changing the water pump to a smaller diameter pump which would make the pump spin faster, so I found a water pump pulley off of a 383 non-ac which is stock and it was approximately 1/2 smaller in diameter. Do not know how a new repop non-ac water pump pulley and a stock one are different diameters, but in my case they are. So I added the old stock smaller one and notice water movement right off, still not what I need but car got to 190 and stayed at that temperature for 16 minutes at idle. After more research I discovered that the stock street hemi water pump is 5 1/2 in diameter which is much smaller thn the big block 440 units. So long story short, If you have a heating problem with your big block at idle take a look at your water pump pulley ratios.

Sounds like the right combination. Stock '68 Hemi has a 6 5/8" crank and a 5 9/16" water pump pulley.

Right now, why do you think you are overheating?

190 at idle after 16 minutes at idle is not overheating.

Do you realize that there is a difference in water pumps for an AC car and a non AC car? Which do you have?

Yes- the car is non-ac and yes I tried both the non-ac and ac water pumps in the car both caused the same problem. Pumps have different fins. I understand I am not over heating at 190 at idle, however I have not pushed the car in 105 heat in Fresno Ca. I just wanted to test a smaller pulley.
I guess I take it out Sunday and run it hard and see what it does.

(What really is frustrating is I was sold on putting the thin 440 damper on the car so I could run the 440 pulleys. They told me it would save me money but in the long run it cost me more in time and aggravation.)

https://bouchillonperformance.com/inc/sdetail/868/903

The with AC pulley is about an inch smaller in diameter than what you have.

I was looking at that pulley. The problem I think I am going to have is with my crank pulley. It is only two grove and I believe this pulley needs a 4 grove crank pulley. I can add that and not run it with the a/c compressor rerouting the belts just like we did back in the day.

One question I have is the statement on the their web page it states under note
3-The BPE4016 is the same diameter as the original single groove style pulley.
Can you tell me how this is true? The single grove pulley does not have a 6 inch diameter it is basically a 7 inch pulley. What am I missing?

They are talking about the original single groove water pump used in early AC setups. That used a tensioner pulley.

http://www.dodgecharger.com/forum/index.php?PHPSESSID=6pp10c63acmkrcu9jccp068m41&action=dlattach;topic=82987.0;attach=154732;image

Vice the later with AC setup

https://www.allpar.com/photos/vintage/1977/440-1977.jpg

Thanks...I think both the single and double grove pulleys use tensioners. I personally never had one on any of the cars I have owned over the years, yet they still did not overheat at idle. I am going to find the old stock single grove pulley used in early ac setup cars and see if I can run it without a tensioner. If not I am going to change my crank pulley and use the two grove a/c water pump pulley that is 5.5 in diameter. I know I can route the belts without the ac compressor.

I dont use the tensioner , I bump the belt on bypassing the tensioner

Are you running a street hemi with a thin damper?

no Hemi just a bb, just giving you ideas