Just how quick were the 273 Commando's in the Quarter-Mile.

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ProStocker273 said:
Hey 69 Cuda 440 my 1965 barracuda has a aluminum flywheel 122 tooth I believe that says weber on it. Is that something that would be used in stock racing back then? Or did I find a marine flywheel. Its for a 9.5 clutch but I've got a 10`` in there now. Sorry for the off topic
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Aluminum Flywheel

That {11 lb.} 'Weber' unit is for a Boat Racer. Nobody running a 273 back then
was running with Lightweight Flywheels.

It was always at least a 30 lb. Flywheel, to keep the Revs up coming out-of-the-hole.
 
318willrun said:
Just saying, if the '65 A-body with Commando 4-speed and 3.55's went a best of 16.03 stock, and my '65 B-body 318 ('85 LA stock using the 273 manifolds the car came with) 2bbl with 2.94's and auto went 15.90's, I'm in for the win, correct? I believe my dragway is at 600ft above sea level, that could be a big difference if the Commando is at 3k

tires.
85 probably had the larger valves.
early 318 LA had same valve size as 273
Click to expand...
 
Regarding the 'LA' 318/230 HP 2-Barrel in the 1968 and later B-Body Mopars.

I never 'ever' saw one get into the 15.90's in Stock Trim.

No way, unless there was a 75 MPH Tail-Wind, and the Track was
angled downwards at a 15* Angle.

They were in the 16.50 range at best.
 
B bodies would also have the 1 7/8 single exhaust for 273 2 bbl?
Original tire width?
85 had roller rocker set-up?
 
Here are some 0-60 and 1/4 times and speeds for the 2bbl and commando 273s from various car magazines of the era -also attached as a pdf
 

Attachments

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ProStocker273 said:
I've heard of 273 cars running 11s and even 10s ( with more current parts, tires, etc) but never seen proof. I'm just curious what one built would run not confined by stock class rules..
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About 10 years ago or so, Mopar Action did a feature on a 10 second A-body. Sounds like no big deal but it was a 273.
 
Clutch Set Ups

Now I remember. When my Mother 'cooked' that Auburn Clutch Assembly in 1968.

My Father called Chrysler Performance {Dave Koffel}, and they sent out a
'Borg & Beck' Pressure-Plate and Clutch Disc that was for a 1953 Dodge Truck.

It had a very 'heavy' spring load-rate unit {#2100 lbs.}.
 
Here's my 273 combo:
OPTIONS:
273 V8 (122K miles)
4.10 sure grip rear,
Edelbrock RPM intake,
Holley 600cfm double pumper,
.515 / .525 Lunati Camshaft
port & polished factory heads,
V-Force Dual exhaust,
factory 4 speed,
around 285-300hp
Feels like a low 14 sec or maybe I can break into the high 13's if I launch her just right!
I've been told a set of headers would really wake her up! Seriously considering it, just wondering if the dollars put out will give me a significant HP boost like 40+ more HPs!
 
318willrun said:
Just saying, if the '65 A-body with Commando 4-speed and 3.55's went a best of 16.03 stock, and my '65 B-body 318 ('85 LA stock using the 273 manifolds the car came with) 2bbl with 2.94's and auto went 15.90's, I'm in for the win, correct? I believe my dragway is at 600ft above sea level, that could be a big difference if the Commando is at 3k ft. Just say'n
Click to expand...


In 1966, my 1965 Valiant 100- 2 door sedan ( listed as 2660 #s in manual) Commando 273, 4 speed, 3.23 non sure grip, stock 6.50 X 13 tires ran a mid 16 sec quarter.
Bought on a used car lot- a retired track car (fenderwell header patches) and had 4.56 gears with sure grip when left dealer- blew the rear on way home from lot- burnouts, hitting the gears.....
 
More 'Back-in-the-Day' Tricks

Performance Tips, without getting into the Engine

Remove the Battery from the Engine Compartment.

Install a 'Heavy-Duty' Battery in the trunk compartment, over the back right rear-end.

'Drag-Shocks' 50/50 {Rear Shocks}

Remove Front Sway-Bar

Fuel Cool-Can

Stewart-Warner Electric Fuel Pump

Air Conditioning Water-Pump

7-Blade Fan

Viscous Fan-Drive

Heat-Riser {3/4"} > between Intake Manifold and Carburetor

Heat Cross-Over Copper Shield {between Intake Manifold and Cylinder Head}

Carburetor Velocity Stack

Carter AFB Carburetor {One size up Secondary Jets, and re-set Pump Shots}
_______________________________________________________________

While it didn't look like a lot, those 'Performance Tips' would knock off nearly
4/10's off a good running '273 Commando'.
 
Cloads -- my '85 motor came from a bone stock Dodge truck. It had flat tappet cam, and standard rockers. I did not rebuild it, only put a car oil pan and new valve stem seals. The exhaust was stock 273 manifolds, with 2" duals out the back (regular mufflers).

69 Cuda 440 - my B-body was a 4 door '65 belvedere. It ran 15.90's multiple times that Saturday. But we have always disagreed on E.T's., which is fine. I know what my car ran, I was there, and in it, and still have the E.T. slip (ha). I've seen a 318 2bbl with 2.76 gears go 15.70's in a '73 dart custom. I personally have had 318 2bbl's in A-bodies that were a little quicker than my belvedere, but didn't get around to getting an E.T. slip.
 
318willrun said:
Cloads -- my '85 motor came from a bone stock Dodge truck. It had flat tappet cam, and standard rockers. I did not rebuild it, only put a car oil pan and new valve stem seals. The exhaust was stock 273 manifolds, with 2" duals out the back (regular mufflers).

69 Cuda 440 - my B-body was a 4 door '65 belvedere. It ran 15.90's multiple times that Saturday. But we have always disagreed on E.T's., which is fine. I know what my car ran, I was there, and in it, and still have the E.T. slip (ha). I've seen a 318 2bbl with 2.76 gears go 15.70's in a '73 dart custom. I personally have had 318 2bbl's in A-bodies that were a little quicker than my belvedere, but didn't get around to getting an E.T. slip.
Click to expand...

318,

Then it did have some performance up-grades.
* Dual Exhaust w/2" Pipes
* Solid Lifter Camshaft .......... Lift ~ Duration ~ Overlap ..... 'Specs' ???
 
69 Cuda 440 said:
318,

Then it did have some performance up-grades.
* Dual Exhaust w/2" Pipes
* Solid Lifter Camshaft .......... Lift ~ Duration ~ Overlap ..... 'Specs' ???
Click to expand...
LOL... where did you read "solid lift cam"?????????? I said a FLAT TAPPET cam, as some 1985's came with a roller cam. Normal, Flat tappet cam like any other 318 LA...lol And, the dual exhaust was on the car when I bought, but I don't think it needed it. It still had the single point distributor that the 273 came with. AND, I couldn't just "mash" it out of the hole, or it would spin the tire to no end (it was a one legger). So, my 15.90's came "eas'n it out of the hole"
 
AJ/FormS said:
318WR
I'm beginning to think your track was a bit short of 1320.
Click to expand...

LOL... I'm used to people selling there mopars performance out for mud. I was done at Cordova Dragway, where I do 1320. If I would have taken it to Earlville, Iowa, it would have gained about 2 1/2 tenths, as that is concrete instead of asphalt, and, it's tilted 4 degrees down hill.
 
I was guessing about a mid-15 second quarter with some full-on 4.56 gears or something similar and maybe a heavier flywheel........I've always wondered about those commando single plane intakes too. Seems like they'd kill a bit of the low-end torque.
 
Gib Warnick said:
In 1966, my 1965 Valiant 100- 2 door sedan ( listed as 2660 #s in manual) Commando 273, 4 speed, 3.23 non sure grip, stock 6.50 X 13 tires ran a mid 16 sec quarter.
Bought on a used car lot- a retired track car (fenderwell header patches) and had 4.56 gears with sure grip when left dealer- blew the rear on way home from lot- burnouts, hitting the gears.....
Click to expand...

Thanks Gib!

2660#'s, 106" w.b., 235 HP
 
Hold On

Correct Shipping Weight

* 1965 Valiant V-100 {2-Door} ........ #2707 lbs.
* 1965 Valiant V-200 {2-Door} ........ #2714 lbs.

An Automatic with 'optional' 3.91 Gears 'Sure-Grip' {7 1/4" Rear} and
'optional' 6.95 x 14" GoodYears.

As long as the Rear could hold up, the 'Lil Valiant' could motor down the
Quarter-Mile in 15.70's.
 
In the 90's and while I was building my race motor (360), I ran my dead stock 318, 2 barrel 904 with 3.23's in an Aussie a-body Valiant. it ran a 16.8
We put a 600 Holley on it and a street torker or something and it ran a 15.2 with no other changes.

My current 273 should run 12's..
 
Johnny Dart

Back in 1968,

My Mother got down into the 14.40's @ 96 MPH with 4.56 Gears, and the previous
listed up-grades while she was running in 'J/Stock'.

Still, nothing done to the Engine yet.

Some issues developed.

#1 > The 'stock' Flywheel was too light, especially when 'off-the-line' Traction was good.

#2 > The 'Valves' now floated at Top-End, stalling any more power.

#3 > The Lifters 'hourglass-shaped' split.

#4 > Several Push-Rods were over-stressed, and 'bent'.
 
mph said:
In the 90's and while I was building my race motor (360), I ran my dead stock 318, 2 barrel 904 with 3.23's in an Aussie a-body Valiant. it ran a 16.8
We put a 600 Holley on it and a street torker or something and it ran a 15.2 with no other changes.
My current 273 should run 12's..
Click to expand...

Well let's look at that for a sec....Quoting from the Direct Connection Performance Book, bulletin #40,dated 1977, and titled: Mopar Bracket Racer Science (price $1.00 back in the day).
Let's say a 12.7 car.
From chart #1, with an unlimited chassis.("an unlimited chassis is representative of what would be used in Super Stock"). This minimum ET (12.7), accompanies a trap of 104mph with an automatic.
From chart #6, this 104mph requires a W/P of 11.0/auto. So that indicates you will need to get your car to run 11 pounds per horsepower.
From chart #4, we see that a realistic raceweight for the 63 to 66 Abodies with A engines is 2900lbs +/- 100.
Now doing the math 2900/11.0=264 HP....Shazzam!
Now to build a 273 to get 264 hp is a whole 'nother story.This is 264/273= .967hp/cid. This is doable but..... takes it near into race motor territory(but then so does the unlimited chassis).
The 273-4bbl engine, from chart #5, had a "rough approximation of the installed,production power level" of 200 to 215hp.(This same chart lists the 340 as 275 to 290, and more importantly, the 318-2bbl as 150 to 170hp). So pumping it up to 264, is about 57 hp additionally.Furthermore 208hp/273=.76hp/cid, a relatively mild figure.
So now to the build. Recall from page 1,that in bracket racing;"there are no rules- you can build the car and engine any way you want". So cam, heads, and Throughput is the plan. You are gonna need to rev this baby. Doable? yes. Expensive? yes.
Now, let's examine the unlimited chassis for a sec. Unlimited. This means the best of everything, and everything working the best that it can. You are looking at gears, a TC, slicks, springs and bars, shocks, everything tuned to hook.All the while staying light, or lighter. And stop at the big end, and steer. Doable?yes. Cheap?no.

But let's say you want to drive this car on the street, cuz, you know, you got all this money in it, and the weather down-under is fine, and it's calling to you. Well, with that pipey engine, the hi-stall, the mega gears, and the SS springs, and the nose-down front, and the loud stripped interior/no mufflers..........um, probably not...........

I know what I'd do, um did............G'day mate, and all the best to you.
 
Not a commando, but I watched a '67 barracuda with a 273 2bbl, auto, single exhaust that was just about as original as you will find. It ran 17.30's. I have no idea what the gears were.
As for me, I've owned 273, and only the 2bbl's. I have never taken one to the strip.
 
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