Pulley Diameters

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Something else discovered along the way when choosing pulleys. Your pulley diameters added together cannot exceed 13". That's all the room there is on an LA small block.

I've also seen 7 1/4" crank pulleys that had a step down groove for the inner belt.
 
Rick Riffle said:
Now I just have to figure out where I can locate a 273 W/AC water pump pulley. Anybody have any leads?
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You may want to check with some people like Laysons, Wild Cat auto wrecking and there are a couple of good sources here on FABO if you look down at the site sponsors section.

That's three off the top of my head for you. None are close to you, but the brown truck knows no limits!!!
 
Tony D'Astingo is another one but damn it I can't remember how to spell his name. That's probably close. IIRC he used to be on FABO.

Any of those named may have what you want or may be able to steer you in the right direction.
 
Here's some pics of the 5 3/4" water pump pulley used. There may be other applications that I didn't list....

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2018-06-25 002 (Small).JPG
 
My thinking was that only so much liquid can pass through the opening of the thermostat so tryig to move more is pointless....apparently I was wrong.
But if this is a car that idles and slow drives in traffic I guess it makes sense.

I think each application might be different and have to wonder about the effects of a very low geared car or a drag car. The concern being the rpms of the fan/pump at 7k thru the traps...

I have changed to an O.D on my Cuda since it is a cruiser with 3.55s but will experiment with the 408 solid roller cam 3.91 geared Swinger.

I had a waterpump shaft shear while reving a 454 so I am a bit nervous about that ...lol
 
mbaird said:
My thinking was that only so much liquid can pass through the opening of the thermostat so tryig to move more is pointless....apparently I was wrong.
But if this is a car that idles and slow drives in traffic I guess it makes sense.

I think each application might be different and have to wonder about the effects of a very low geared car or a drag car. The concern being the rpms of the fan/pump at 7k thru the traps...

I have changed to an O.D on my Cuda since it is a cruiser with 3.55s but will experiment with the 408 solid roller cam 3.91 geared Swinger.

I had a waterpump shaft shear while reving a 454 so I am a bit nervous about that ...lol
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You're correct that there are restrictions in the system. That's one reason why the system is under pressure. It's also another reason why I used Evans coolant. It won't build pressure. I can pull the cap right after I park the car and it doesn't explode all over the place.

There are several high flow thermostats out there. Some are better than others. The best I've found is Stewart Components. IIRC they are the Robert Shaw thermostats. You can get more flow with a higher pressure to a point.

Again...FLOW is your friend.
 
What’s the p/n for the water pump to to ps belt with the 5 3/4 pulley that you used?
 
TRWRacing said:
What’s the p/n for the water pump to to ps belt with the 5 3/4 pulley that you used?
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I don't think my belt # will help you since my PS pump runs off the crank pulley by itself...

Power Steering >> Crank

Air Conditioning >> Crank

Alt & Water Pump >> Crank
 
Put 270 miles on the car yesterday, including climbing from 1000' to 7000' elevation and back. AC was running most of the time, including during the climb. Car temps never went over 200*. Cool -- Cool :D

I'm now convinced the cooling system problems are over for ME. Hope someone else benefits from this info!

Stay COOL :thumbsup:
 
@6pk2goDemon so your original combo was an A/C water pump(6blades) under driven with 1:1 aftermarket pulleys.
With the current set up, are you spinning the pump at a factory AC ratio, or non-AC ratio?
 
plumkrazee70 said:
He doesn't deal in parts anymore. @whitepunkonnitro was his nam here.
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I thought that was two different people. I see Tony on Grave Yard Cars and I think whitepunkonnitro was a guy who started his own business but at one time was working on fuel cars and various other stuff like that.

I may be wrong though, because I often am wrong. My wife will vouch for that.
 
6pk2goDemon said:
Put 270 miles on the car yesterday, including climbing from 1000' to 7000' elevation and back. AC was running most of the time, including during the climb. Car temps never went over 200*. Cool -- Cool :D

I'm now convinced the cooling system problems are over for ME. Hope someone else benefits from this info!

Stay COOL :thumbsup:
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Isn't is nice to KNOW you can go anywhere and not worry about temp? Glad you got it sorted out and I'm sure this will come up again. This thread will be helpful.
 
JoeSBP said:
@6pk2goDemon so your original combo was an A/C water pump(6blades) under driven with 1:1 aftermarket pulleys.
With the current set up, are you spinning the pump at a factory AC ratio, or non-AC ratio?
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Original combo was a 6 blade AC water pump with a matched pair of 6 1/2" diameter billet aluminum pulleys, so yes 1:1

Current ratio is 1.26:1. Not sure if that's the factory AC ratio or not?? There is some info on that earlier in the thread posted by other members. All I know is it works.....:)
 
I was just thinking with the difference between the water pumps, you may be able to keep your pulleys, just upgrade the pump
 
JoeSBP said:
I was just thinking with the difference between the water pumps, you may be able to keep your pulleys, just upgrade the pump
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It's possible & the water pump would have been my next change if the pulleys didn't improve the issue. I didn't mind changing to original pulleys at all. The billet pulleys were purchased many years ago & looked great, but removing them has fixed my car. No big deal, as I'd much rather have it run cool than look cool :)

There are SO many variables with different builds. This is just another avenue to explore that hasn't been discussed much from the research I've done in the past.

Thanks for your input Joe!
 
yellow rose said:
I thought that was two different people. I see Tony on Grave Yard Cars and I think whitepunkonnitro was a guy who started his own business but at one time was working on fuel cars and various other stuff like that.

I may be wrong though, because I often am wrong. My wife will vouch for that.
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Oh maybe. Tony Defeo is @whitepunkonnitro.
 
Service manual for ‘73 states 1:26:1 for non A/C 340. And 1:30:1 for A/C for a ‘73 340. What pulley combo to get to that? Looks like the crankshaft is either 7.25 or 7.375 measuring it approx on the vehicle.
 
Found a '73 Parts manual (score!)

340 with A/C Crank pulley: P/N 3671320 7 3/8"
WP pulley: P/N 3418227 5 5/8"
1.31 ratio for Max Cooling, which I believe I already have. I will confirm the WP pulley when I pull it apart. I am running at 210+* just right of the middle of the stock gauage (confirmed with Autometer gauge installed as well) without the A/C running with 180* high flow thermostat and 6 vane WP on a newly rebuilt engine ~700 miles ago. 26" Core 2 row radiator will be getting replace with HE 3 row US radiator.
 
TRWRacing said:
Found a '73 Parts manual (score!)

340 with A/C Crank pulley: P/N 3671320 7 3/8"
WP pulley: P/N 3418227 5 5/8"
1.31 ratio for Max Cooling, which I believe I already have. I will confirm the WP pulley when I pull it apart. I am running at 210+* just right of the middle of the stock gauage (confirmed with Autometer gauge installed as well) without the A/C running with 180* high flow thermostat and 6 vane WP on a newly rebuilt engine ~700 miles ago. 26" Core 2 row radiator will be getting replace with HE 3 row US radiator.
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It funny all this is public knowledge and yet the aftermarket still makes junk pulleys in the wrong diameters. How many guys are fighting cooling issues right now because they don't run the pump at the correct speed?
 
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