Need help with water pump pulley

[Dmichels]

Working on an ac conversion 440 w power steering and correct pulleys and belts for non ac car. The aftermarket ac bracket I am using works with the current pulley set up but has the compressor driving off the one inner alternator belt. The power steering belt needs to drive the water pump now with this set up. Can any one tell me the part number for the water pump pulley that aligns with the power steering pump? This would be the second grove out on the crank pulley. I am using the brackets from nostalgic air.
Thanks Dave

[cdr]

Working on an ac conversion 440 w power steering and correct pulleys and belts for non ac car. The aftermarket ac bracket I am using works with the current pulley set up but has the compressor driving off the one inner alternator belt. The power steering belt needs to drive the water pump now with this set up. Can any one tell me the part number for the water pump pulley that aligns with the power steering pump? This would be the second grove out on the crank pulley. I am using the brackets from nostalgic air.
Thanks Dave

contact These people
https://www.bouchillonperformance.com/home

[Kern Dog]

This is the factory arrangement:

[Kern Dog]

Last year, I converted to A/C in my car. I was determined to do it with 3 belts instead of 4 because I wanted to skip the idler pulley. I wanted to have the crank drive the water pump and power steering on 1 belt with the alternator and A/C compressor on 2 belts.
I posted about it at FBBO and had a few members advise against it based on the understanding that the water pump pulley would squeal and slip since it would only have about 90 degrees of belt contact.  The power steering would have had almost 120 degrees of contact. The reason the A/C compressor has 2 belts is because the limited belt contact with 1 belt makes it a lot more likely to slip.
I wanted a cleaner look but ended up admitting that the factory chose the 4 belt arrangement based on engineering, not appearance. Mine does not slip.

This is a spare engine I used to mock it all up instead of leaning over the car. The power steering was still in the car.

[Dmichels]

Thanks for the help just trying to keep things simple

[Nacho-RT74]

Last year, I converted to A/C in my car. I was determined to do it with 3 belts instead of 4 because I wanted to skip the idler pulley. I wanted to have the crank drive the water pump and power steering on 1 belt with the alternator and A/C compressor on 2 belts.
I posted about it at FBBO and had a few members advise against it based on the understanding that the water pump pulley would squeal and slip since it would only have about 90 degrees of belt contact.  The power steering would have had almost 120 degrees of contact....

73 and lates are with 3 belts, BUT the steering pump on these sit lower into the engine bay, correcting the belt contact with water pump you are mentioning.

Also the lower WP outlet is on passenger side, allowing the room for the lowered steering pump ( and air Pump on C bodies )

[Kern Dog]

I don't recall ever seeing that. My arrangement is already figured out but I would like to see other setups just to see the differences.

[Nacho-RT74]

Stock photos posted here about the 73 and lates setups ( with and without air pump)

http://www.dodgecharger.com/forum/index.php/topic,138483.0.html

[rockosocko]

Last year, I converted to A/C in my car. I was determined to do it with 3 belts instead of 4 because I wanted to skip the idler pulley. I wanted to have the crank drive the water pump and power steering on 1 belt with the alternator and A/C compressor on 2 belts.
I posted about it at FBBO and had a few members advise against it based on the understanding that the water pump pulley would squeal and slip since it would only have about 90 degrees of belt contact.  The power steering would have had almost 120 degrees of contact. The reason the A/C compressor has 2 belts is because the limited belt contact with 1 belt makes it a lot more likely to slip.
I wanted a cleaner look but ended up admitting that the factory chose the 4 belt arrangement based on engineering, not appearance. Mine does not slip.

This is a spare engine I used to mock it all up instead of leaning over the car. The power steering was still in the car.

Couldn't you just lift up the tensioner pulley so it would be in between the pump and crank pulley's, then use a 'flat' tensioner pulley "pushing" the belt inwards instead of pulling outwards. That should give more 'grip' to the pump.
But I wouldn't think it would screach at all, being the pump doesn't take that much to turn. Unlike the compressor
or alt (depending on amp draw)

[Kern Dog]

The water pump takes a lot more to turn than the alternator does. The Power steering takes about 4-5 HP.
I appreciate your ideas about reversing the idler. That is what the newer cars have. There is no room here and the pulleys are designed for the belt to fit inside due to the tapered shape of the belt. New ribbed belts are flat.

[John_Kunkel]

The water pump takes a lot more to turn than the alternator does.

"Calculated by the National Renewable Energy Laboratory) an alternator of sufficient size will take up around 10bhp (calculated by ZENA, DC motor specialists) when the engine is under full-load.

For the water pump, things aren't so simple. Since it shares a relationship with engine speed, the power needed to spin the impeller of the pump forms a cubic relationship with the powertrain's reciprocation. This was researched by automotive cooling experts Davies Craig that found that water pumps used 0.13bhp (0.1kW) at 1000rpm, 1.1bhp (0.8kW) at 2000rpm and 8.6bhp (6.4kW) at 4000rpm."

[Kern Dog]

Hmm...Maybe I remembered it wrong.
One of the Mopar magazines did a series of tests where they learned the parasitic draw of the various engine components. Air filters, pumps, etc.
I thought I recalled seeing that the Mopar alternator was around 3-4 HP, the water pump was about double that while the power steering was somewhere in the middle.

[XH29N0G]

KD,  It might all be in the RPM and you might not be misremembering.  

John's post said the data should follow a cubic law, meaning that the HP draw would be related to the RPM cubed times some constant.  If I take the data he shows and fit a cubic law to it, I get something like HP = 0.0000000001*RPM^3, which gives 12.5 HP at 5000 RPM and 21.6 HP at 6000 RPM.  

The alternator would also be at full draw.  I do not know what it is when not drawing.  Presumably the PS pump also goes up when going around corners and down when going in a straight line.  

My guess is that there is a base number when they are not drawing, simply related to resistance, and then there may also be something related to inertia when we are spinning up the RPM.  What I do not know is whether the amount due to inertial change is significant or insignificant.

This is where we need some engineers.  I would really like to know the answer from someone who knows this stuff (or can figure it out) so if someone does, PLEASE educate me (us).  I'm going to go downstairs to see if my son knows.  I'll report back if it is really straightforward and I understand what he says.

EDIT:  SO I asked my kid and he said that he imagines the inertial effects are probably pretty minor considering all the other rotating things on the engine.  Then he said flywheel, wheels, etc.....  He then dissed our cars by saying that he doesn't imagine that our cars are super high tech.  But I'm still talking to him because he let me have some of his stroop waffels (or however that is spelled).  But I don't actually know how much the inertial change would be.  I suppose I should start looking into how it is calculated.

I need to look into it more, but if I calculate it right (I get about 600 rpm rise per second in third gear) I am not getting this as zero for the tires or even for the alternator and PS pump.  Only a small amount for the latter two, order a ft lb or a two.  But it looks like If I shave 10 lbs off my tires, it could make a difference I might see because it looks like it uses between 10-20 ft lb of the engine's torque.  I hope my math isn't way off.