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Sounds like M21 and 4:11 gears. M20 was the wide ratio as I understand. But gear sets can be interchanged so you might have to disassemble to really know. Figuring out the rear is relatively easy. Jack up, spinn the rear wheel and count the driveshaft rotations.
 

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IMHO if replacing points/condenser I would switch to a Pertronix kit in your stock dizzy and get the Pertronix coil also.

If you feel the plug wires need changing decide on which type you want. Over or under valve cover routing. You can make your own or buy pre-made. If over the VC wires using stock wire loom bracket that attaches to VC bolt, I found the Moroso 8.5's fit great

1967 CHEVROLET CAMARO Moroso 73706 Moroso Ultra 40 Unsleeved Custom-Fit Wire Sets | Summit Racing

Whatever carb you have you should be able to download a PDF manual for it

Timing light and vacuum gauge are your friends in checking, adjusting timing & carb

Assuming your speedo is right, 3200 rpm at 60 would be at least 3:73, maybe even 4:11's if you have tires that are 27". You can use the Speed Box APP to see what GPS speed vs your speedo says. Speedo gears are around $7 and each tooth +/- (reading to slow or fast) is about 5 mph difference. This calculator will help once you find out what rear gear ratio & tire size you have

Speedometer Driven Gear Calculator (stl-vettes.com)

If you can pull any #'s off the trans that should identify what Mxx it is

when changing diff fluid and checking out gears if it's a posi, clutch type, you will need a 4oz bottle of friction modifier (GM or Ford is fine) to add to the non-synthetic gear oil (read clutch type posi do not what synthetic gear oil).
 

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@fairfax1000 yep, thats the plan. It does run a little rough. I will be doing typical maintenance - oil change, air filter, points condenser, cap, rotor, plugs and wires. Also change the tranny fluid and diff fluid. As someone mentioned previously, I will cut open the oil filter. And I want to peak in the rear end anyway - and figure out what gears it has (I know I can do that whithout opening it up).

I took a quick spin today, I am still not 100% convinced it is a M22, but I am pretty certain it is close ratio. Gears are low, I am thinking 3:73 or lower. I don't think the speedo reads right, if it does I was revving around 3300 at 60mph (ouch!). More to come... should I be putting this info in a new thread in a different section?
I’d start a new thread. This might help

 

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Discussion Starter · #44 ·
@SoCal805 after more research, I think this is the plan for now, but may replace distributor with new Pertronix unit, or something else (MSD, Mallory, Holley - so many choices). Going to search in other sections/sites for info.
I have a rebuild kit for the 3310/4160 Holley carb, plug wires and looms (going over valve cover). I have new valve cover gaskets too, may as well prevent a leak now and take a peak in there and see what it looks like... sounds like cheap insurance.
 

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I would suspect 3.73 gear and a M 21 close ratio. 🤔
 
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