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indirect_connection

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I need some help ID'ing my v-belt set up. The car is a 68 Dart, the motor is currently a 273. Not sure of the year, but it does have hydraulic lifters. It originally had AC, but the compressor is no longer installed. I'm afraid it has been cobbled together, and will make reinstalling the AC a pain. The alternator has a two groove pully, with three groove on the crank. There is also a tensioner than is not being used.

I also want to verify that the water pump/radiator are the early style and not post 70.

I'm rehabbing a Magnum, and would like to swap the timing cover and accessories.

Pictures to follow.
 
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That is definitely cobble together. May be pretty tough to make you have there work. BTW Mr.JLR, that is what my wife calls me, as those are her initials...
 
The thing is there are many changes to the drive systems over the years. One thing I can tell you DO NOT lose track of that idler setup. There are people who "want" it. However, I believe the idler belongs on the BACK side of the belt

The timing marks and lower hose are certainly "early" I think then changed in 70? Both on opposite side
 
Radiator: Round Top = Early 63-69
Water Pump: Iron + timing marks on the right = Early
Ditch the tensioner, not needed.
No idea on the AC.
 
It looks like an a/c compressor could tie in with the ps pump belt. I'm not sure what the stock setup is. I haven't been able to find a picture of the stock routing with ps and ac.

My radiator is leaking and will need replaced anyway. Is there any advantage to switching to the 1970 and later setup? Seems all the aftermarket setups require 1970 and later water pumps.
 
The 70 and newer set up is easier to source the pieces you need. The A/C compressor for the 69 and earlier utilized a single belt, definitely going to be harder to find a compressor with the single groove clutch set up. If you go to the 70-up setup, it will require a different timing cover. aluminum water pump, dual groove A/C clutch set up, different P/S pump and brackets and a radiator with the lower hose neck on the opposite side.
 
The early small block A/C set ups are very complicated (cast iron water pumps) . Everything must match to work properly . I believe you need a 4 groove crank pulley . 2 grooves drive the alternator A/C compressor, 1 drives the waterpump and one drives the power steering pump . The idler adjusts the water pump tension , the alternator adjusts the tension on the alt.,A/C and the power steering is adjusted at the pump . Note : you can't use non-A/C brackets on A/C cars and visa-versa except for the water pump pulley . Just won't fit AIRC
 
I am working on converting my 69 to an original a/c belt setup. I will post pictures when I do it. Might not be for a month or two.
There a a couple of threads on here with good pictures. I think one is “I Need info on 68 340 pulleys”
 
If you change to a 70 up radiator you basically have to throw away everything on the front of the engine & your timing marks may be hidden. I bought a 70 up water pump & was going to do it & decided it was a lot of expense & work for nothing.

Still got a new water pump if anyone wants one.
 
The early small block A/C set ups are very complicated (cast iron water pumps) . Everything must match to work properly . I believe you need a 4 groove crank pulley . 2 grooves drive the alternator A/C compressor, 1 drives the waterpump and one drives the power steering pump . The idler adjusts the water pump tension , the alternator adjusts the tension on the alt.,A/C and the power steering is adjusted at the pump . Note : you can't use non-A/C brackets on A/C cars and visa-versa except for the water pump pulley . Just won't fit AIRC
On the 70 up set up, 2 belts drive the alt and comp. One belt drives the W/P and P/S. No idler needed.
 
If you change to a 70 up radiator you basically have to throw away everything on the front of the engine & your timing marks may be hidden. I bought a 70 up water pump & was going to do it & decided it was a lot of expense & work for nothing.

Still got a new water pump if anyone wants one.

Juz sayin, and OT but the timing marks are EASY to deal with. go ahead and change the timing cover, then use a piston stop to remake TDC and mark it so "you know."
 
It has a non a/c w/p pulley. If I change to the newer style as noted it’s a lot easier to get parts. The dampner can be reused. U can measure from the factory mark to where u need the new mark. As said u need to change the timing cover and water pump. U will also need an A/C top pulley. Kim
 
I think the 70 and later water pumps are also taller than the earlier ones to make room for the double belts. Not necessarily a big deal, just nice to know if you are planning on keeping original fan and spacer.

A clutch fan would be a nice addition, would quiet it down some.
 
From what I can see, a previous owner used the correct pulleys to do an 'airco-delete' setup.
If you want airconditioning again you need the correct matching pulleys AND that tensioner.
 
gilmer belt takes less hp to drive
fan clutch is a must why else do a swap
remember a magnum/ gilmer belt water pump runs backward, different fan and clutch
Mopar actually makes clutches with different temp operating springs
There is a service bulletin for my 92 dakota where they upped the clutch temp 5-10 degrees and went from a 7 blade 3" pitch to a 9 blade 2 1/2 inch pitch to reduce coming on at stoplights and the noise which was like a 747 with the 3" pitch fan
92 was the first year for the magnum and since i had done cooling R&D tests many years ago I knew where to write with comments on the noise of the early Dakota and Ma Mopar listened
Now GM has a 11 blade plastic fan that I want to try
 
Serpentine belt is better, and would be the easiest way to make this engine swap. I agree. But it does look out of place in my opinion, especially with the high mount truck orientation. Plus I would lose the mechanical fuel pump. I've already done the modern engine/fuel injection swap on another car. I want to keep this one a little more old school.

So why use a Magnum?
Availibility. Modern build quality. Factory roller cam. Biggest reason though is the best chance of building an engine without ever setting foot in a machine shop.
 
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