Pulley selection and Belt Routing

[rr03cobra 3]

Sorry if this has been answered before but I couldn't find it in a search. I have a 351W that I added AC (VIntage Air), rack and pinion w/power steering (Unisteer) and a 140 amp 1 wire alternator (CVF racing).  Do I need a 3 groove water pump pulley and a 3 groove crank pulley? Does anyone have a belt routing diagram for this?  The car currently has a 2 groove pulley for both.  The power steering is the one not lining up but I have a spacer to make it work if need be. If I go that route I'm having a hard time finding a bolt that long (7/16-14 at 7.25" long).  Also, would it be better to go to a serpentine setup due to the current rating of the alternator?

Thanks for the help.....Rich

[Mach1 Driver 560]

It is recommended that any alternator over 95 amps have either a serpentine belt system or two v-belts, so as not to slip. If you change to serpentine, then you'll need to ditch the fan and go with electric cooling. Personally, I would ditch the 140A alternator and get a 95A. It should be more than enough power. Ya, its a bummer, but a case of more not being better.

My bone stock 351w with PS and AC has a three groove pulley on the crank, and a two on the water pump. 

[rr03cobra 3]

I saw your post about the 95A alternator so that's why I brought it up.  The car will have electric fans, electric windows, ac, efi and some amps so that is why I went with the larger alternator. I'm upgrading all the wiring now with a new kit from AAW.  I didn't want to spend the money now on a serpentine system until I upgrade the motor and cooling.  How did you route the belts on the crank? Does one only go the PS?  thx for the help

[Mach1 Driver 560]

There are three belts. The closest belt to the engine goes around the crank, water pump, and the alternator. The second forward goes to the crank, water pump and PS. The third goes to the crank, bottom idler, AC, and top adjustable idler.

 

 

[det0326 179]

just another option is if u don't mind the look and changing water pump to reverse rotation u can use late 80s to early 90s f150 brackets. that will get u serpentine belt and all acc's will line up.  If u have stock A/C u would have to change compressors too tho. That might be getting into a needless money pit 

[rr03cobra 3]

thanks for all the help guys. I'm going to change the PS pulley and see if I can get it to line up.  Once I get all the wiring done I will see how the V-belt system works with the alternator. If it slips than I guess I will change to a serpentine system. here a picture of it lined up with the spacers.  

[Mach1 Driver 560]

That's the first double-v pulley I've noticed on a classic Stang AC system. Is that a common thing on the aftermarket units?

[Rich Ackermann 174]

Many (but not all) of the accessories and brackets are the same on the Windsor and Cleveland small blocks. I have a 351C with a Tuff Stuff 140 amp Alternator, A CPP (Borgeson like) Saginaw Powersteering pump and Vintage air Sanderson A/C compressor. There are no v-belt accessory brackets on earth that support this combination. I used a stock 351C three groove crank pulley, and stock single groove Water Pump and Alternator pulleys.  The passenger side alternator, brackets, and v-belt are a slam-dunk stock setup. On the drivers side I had to make the P/S and A/C brackets by combing a few stock brackets, a couple of brackets available from the aftermarket, and then I had to make a bracket, modify a couple, and make all the spacers. Finally fine the right side v-belts. PS. I only used high quality toothed Belts. I have read that these belts grip better.

In my humble opinion, to avoid belt slippage/squealing/wear, it is important to have the alternator belt on its own and on the middle groove on the crank pulley and the A/C compressor dedicated on the large outer groove. The Water Pump and P/S pump share the inner most groove. It took me a lot of time and trial and error to make certain all the accessory pulleys were on the same plain with their counterpart groove on crank pulley and also that the accessory pulley was square with the belt and then make the right length spacers. Leaving any angle in the belt forward/back or tilt left/right in the pulley will cause the belt edge to fray in a hurry.

 

 

[Mach1 Driver 560]

Rich, that is a well done and thought-out belt system. All that contact with the crank and alternator pulleys certainly gives it a lot more traction than the stock set-up. I'm curious how well it does when that 140A alternator is at full charge and everything is hot. I think you have a winner there.

My only thought is that the water pump and fan only have about a 1/4 turn of one belt pulling them, and that same belt is driving the PS, but road testing will tell the tale. Have you put any miles on it yet? Please keep us posted.

[Rich Ackermann 174]

2 hours ago, Mach1 Driver said:

Rich, that is a well done and thought-out belt system. All that contact with the crank and alternator pulleys certainly gives it a lot more traction than the stock set-up. I'm curious how well it does when that 140A alternator is at full charge and everything is hot. I think you have a winner there.

My only thought is that the water pump and fan only have about a 1/4 turn of one belt pulling them, and that same belt is driving the PS, but road testing will tell the tale. Have you put any miles on it yet? Please keep us posted.

I have been driving the car on the road since October 1st and its been running fine for most part. After a month I experienced some slippage (squealing) on the alternator belt when I would rev the engine quickly, so I tightened the belt a bit more an she has been quiet since. Hopefully it will stay that way. The P/S pump belt width and V angle fit the Saginaw pulley perfectly, but sit a bit deeper than stock in the grooves on the crank and water pump pulleys, but so far no issues. I do feel the hydraulics straining a bit when turning the wheels from stop to stop at a stand still, but that is partly due to the wide front Nitto tires putting more resistance than stock tires. I should mention, That the P/S pressure hoses do not mind bending, but they do not like and flat out refuse to be twisted. To my surprise, I had quite a bit of difficulty finding the right high pressure fittings needed to clock the P/S hoses so I could connect them to the back of the Saginaw pump. I think adding the 71-73 over the A/C  compressor P/S fluid cooler will help keep the system cooler when driven hard on those hot summer days.

Overall, I am pleased with the results so far. With the two adjustable Saginaw pump brackets on the front and back and the long 7/8" dia bolt running thru the three brackets and in to the stock accessory hole in the head, they setup is solid and does not flex when tightening up on the v-belt. Very important to square off your pulleys and get them on the same plain as the crank and water pump grooves to minimize resistance and prevent fraying the belt edges.

What I have not hooked up and tested yet is the A/C belt, but I don't anticipate any issue there. The belt grooves on the Sanden and the crank pulleys match, and the crank pulley is designed to drive the old York Compressor, but that test will not happen until sometime in the spring. Here are a few more pictures...

 days.

 

[Mach1 Driver 560]

The stock AC has an additional idler pulley on the drivers side, and I'm not quite sure why its there. It doesn't route the belt around anything. Maybe the long run of the belt from the crank to the AC makes the belt flap around if its not there?

[aslanefe 333]

9 hours ago, Mach1 Driver said:

The stock AC has an additional idler pulley on the drivers side, and I'm not quite sure why its there. It doesn't route the belt around anything. Maybe the long run of the belt from the crank to the AC makes the belt flap around if its not there?

Yes, without that idler pulley the belt flaped around with the original York style compressor before I changed to Sanden. With Sanden, I do not need that pully. 

[Rich Ackermann 174]

17 hours ago, Mach1 Driver said:

The stock AC has an additional idler pulley on the drivers side, and I'm not quite sure why its there. It doesn't route the belt around anything. Maybe the long run of the belt from the crank to the AC makes the belt flap around if its not there?

 

7 hours ago, aslanefe said:

Yes, without that idler pulley the belt flapped around with the original York style compressor before I changed to Sanden. With Sanden, I do not need that pully. 

You both referring to this one picture below, the second non-adjustable idler pulley,...correct?

Did it flop around with the York Clutch engaged, or disengaged, or both? Just curious as I have a factory setup on my 73 Vert with a 351C and a York Compressor, but I never reinstalled this second pulley. I have never charged the AC system, so  the clutch wire is disconnected. With the York style clutch (permanently) disengaged I don't see a flopping issue without the second  pulley, so I now wondering if the flopping happens primarily when the clutch is engaged and under load?

What do you think...?

[Mach1 Driver 560]

Yes that's the pulley I'm referring to. I'm guessing that the flapping issue only presents itself when the old style compressors are engaged, since they have a jerky piston motion (mine vibrates horribly but continues to operate) versus the Sanden which is often referred to as rotary. I've never removed the pulley to investigate.

I found this about the Sanden: Even though it is commonly referred to as a rotary, it is not. The Sandens are so popular because they operate smoothly, with a minimum amount of torque required to operate, because the load is distributed over multiple short-stroke cylinders. ... These characteristics make the Sanden an almost ideal performance compressor.

[aslanefe 333]

1 hour ago, Rich Ackermann said:

 

You both referring to this one picture below, the second non-adjustable idler pulley,...correct?

Did it flop around with the York Clutch engaged, or disengaged, or both? Just curious as I have a factory setup on my 73 Vert with a 351C and a York Compressor, but I never reinstalled this second pulley. I have never charged the AC system, so  the clutch wire is disconnected. With the York style clutch (permanently) disengaged I don't see a flopping issue without the second  pulley, so I now wondering if the flopping happens primarily when the clutch is engaged and under load?

What do you think...?

Yes that non adjustable pulley. Yes flopped when AC was running (clutch engaged); did not flop when AC was not running (clutch disengaged).

[Rich Ackermann 174]

On 1/6/2022 at 7:02 AM, Mach1 Driver said:

Yes that's the pulley I'm referring to. I'm guessing that the flapping issue only presents itself when the old style compressors are engaged, since they have a jerky piston motion (mine vibrates horribly but continues to operate) versus the Sanden which is often referred to as rotary. I've never removed the pulley to investigate.

I found this about the Sanden: Even though it is commonly referred to as a rotary, it is not. The Sandens are so popular because they operate smoothly, with a minimum amount of torque required to operate, because the load is distributed over multiple short-stroke cylinders. ... These characteristics make the Sanden an almost ideal performance compressor.

Thanks All! Once I get the Sanden system charged on the 70 Mach this spring and start to use it, I'll keep an eye on the belt behavior. I may never use the stock Yorke compressor setup on my 73 Vert, but I guess I should install the second pulley anyway as that is how it came from the factory.

[Zachary 0]

Hey Rick love the information u put are their does that system of pulley setup work with water pump outlet on the passenger side too or just on the driver side