273 "commando"

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I am pretty sure the crank is the same
Both the 180 horse and the 235 horse cranks were forged. I've never owned a automatic car so I am not certain if both are drilled for a pilot bushing. The early automatic cranks did have a smaller torque converter register.
 
Advertised 10.5 CR. If you measure the stock deck height, how far the piston sticks out of the block, the

Stock cc of the 920 head and the thickness of the steel shim gasket you are looking at a true CR at about 11-12 CR. You'll have to do the math.
 
Im smack dab in the middle of a auto to 4-speed swap in my 65 gt with the hi-po 273. The hole in the crankshaft is not finished reemed for the standard pilot bushing. My pilot hole is .905 they make an un-finished size bushing Thats .915 o.d. just took a few .000 off and drove in nicely.
 
Two bbl rated at 180hp, Commando rated 235 hp.
Ha, I knew that. I was asking a question back to 66fish when he asked "what's the difference at the crank". I didn't know what he meant. He was asking about the pilot bushing bore. When you talk about horsepower it's either "at the crank" or "at the wheels". (but you probably already know that.)
 
Im smack dab in the middle of a auto to 4-speed swap in my 65 gt with the hi-po 273. The hole in the crankshaft is not finished reemed for the standard pilot bushing. My pilot hole is .905 they make an un-finished size bushing Thats .915 o.d. just took a few .000 off and drove in nicely.

This is what i thought.
Thanks
 
Im smack dab in the middle of a auto to 4-speed swap in my 65 gt with the hi-po 273. The hole in the crankshaft is not finished reemed for the standard pilot bushing. My pilot hole is .905 they make an un-finished size bushing Thats .915 o.d. just took a few .000 off and drove in nicely.


What about using the pilot bearing they call the "problem solver" that installs in front of were the pilot bushing goes?

It says it made so you don't have to use a pilot bushing
 
Just an example. I had never heard of them before. I just posted a link. The application listed small blocks but not specifically 273.
 
I have one of those problom solver bushings as well. Only its a bushing not a roller.(ill NEVER use a roller bearing on the input shaft. Seen to many fail & ruin the inputshaft!) But the early small converter pilot hub wont let it fit. So it will need to be turned down to fit the small crank register of the 64-65 273's.
The pilot bushing thats .915 o.d. is for automatic un finished pilot holes. I just had to take a few thousands off it to get the proper ..003-.004 interface fit since my pilot hole is .905.
 
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I have one of those problom solver bushings as well. Only its a bushing not a roller.(ill NEVER use a roller bearing on the input shaft. Seen to many fail & ruin the inputshaft!) But the early small converter pilot hub wont let it fit. So it will need to be turned down to fit the small crank register of the 64-65 273's.
The pilot bushing thats .915 o.d. is for automatic un finished pilot holes. I just had to take a few thousands off it to get the proper ..003-.004 interface fit since my pilot hole is .905.

Thanks
I'll skip the roller bearings.
My 273 casting year is 10-1965 stamped with the 1966 B.
So do you know if the 1966 hole is different on the 273
From the 1964/1965

I'm going to be using a 1964 a833 4sp
 
Far as I know its a 50/50 shot of being
Finished reemed pilot hole or not. I used telescoping T to mic my pilot bore. As far as converter hud changes I thought it was 66-up when the hub went bigger.
 
65 4bbl had a pop-up piston, it was a pent-roof design so it fit into the 080 head I assume as the chambers were 'closed' per val and mike. If you can see 2 valve reliefs through the spark plug hole, your looking at a 2bbl piston. If its smooth on the plug side, its a 4bbl piston. Good luck on seeing them though.
 
2bbl on the right, 4bbl on the left.

20160320_215000.jpg
 
I wouldn't pull the head just to check the piston type. Buy a USB "endo-scope video camera" on ebay. I paid ~18 and has paid for itself many times. The head is ~1/4" D and easily fit thru an O2 sensor port (to view catalytic converter), which I think are the same thread as larger spark plugs so "should work". Has a built-in LED light. Plug into a notebook PC and use standard Windows accessory software that works w/ any USB camera.
 
66 dual point I found a couple summers ago under the drivers seat of a 66 barracuda sitting in a yard in utah. Still around if lucky..

An oem 13" rusted out cragar was also in the trunk.. sent the trunk lid to a friend...
I would be interested in the Cragar wheel!
 
I see dual point 273 distributors on ebay all the time. Is there something different about the Commando distributor?
 
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