1968 Valiant '318 Commando'

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69 Cuda 440

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In 1968,

Mopar had the 340 'High Performance' for the Barracuda.

Advertised at 340/275 HP, it was quickly factored and rightfully so
by the NHRA to 310 HP.

On the 'Junior-Engine' side, was an over-rated 318/230 HP {2-Barrel}
with a woefully under-sized Carter BBD Carburetor.

The NHRA corrected this 'wildly' rated engine back to down to it's
logical rating of 195 HP.

That left a gap of 115 Horsepower between the 340 'Mini-Hercules' and
the low-revving but durable 318.

Product Planning, left with a 'gaping hole' for a Junior Performance Package,
almost pulled the trigger on a '318 Commando', for the 1968 Valiant.

3984750429_459ef383ff_z.jpg
 
I wish I could find the pre-production specifications, for the 1968 V-100
Valiant-S '318 Commando'.

I believe a '318 4-Barrel' was also planned for the 1968 Dart GT.

I know for a fact, that a Carter 4-Barrel and Dual-Exhaust was part
of the pre-production spec sheet.
 
Found some information,

1968 '318 Commando' available in either the V-100 or Signet.

Standard equipment was with the 'up-graded' Suspension, with 1" Firm-Ride
Shocks, and 6-Leaf Rear #110 lbs. Load-Rate Leaf-Springs, HD Front Anti-Roll
{Sway Bar} and .088 Torsion Bars.

* 14 x 5.5" Rims with D-70 x 14" Tires

* 4-Speed Manual Transmission with 10.5" Clutch Package
* 3-Speed Torque-Flite Automatic A-904, with Heavy Duty Clutches

* 8 3/4 Rear-End with Sure-Grip

* Dual-Exhaust, including the Decor Package Chrome-Tip extensions.
 
Frank,

There really wasn't that much of a difference between all the 1968 Chevrolet 327' Engines.

327/210 HP {Base Engine}
Compression Ratio.....8.75-1
Cylinder Heads..........68.8 CC {1.72" Intake ~ 1.50" Exhaust}
Rochester 2GV..........381 CFM {2-Barrel}

327/250 HP {Code L73}
Compression Ratio.....8.75-1
Cylinder Heads..........68.8 CC {1.72" Intake ~ 1.50" Exhaust}
Rochester 4MV..........650 CFM {#7028213}

327/275 HP {Code L30}
Compression Ratio....10.0-1
Cylinder Heads.........57.7 CC {1.94" Intake ~ 1.50" Exhaust}
Rochester 4MV.........650 CFM {#7028213}

327/300 HP {Code L75}
Compression Ratio....10.0-1
Cylinder Heads.........57.7 CC {1.94" Intake ~ 1.50" Exhaust}
Rochester 4MV.........750 CFM {#7028207}

Note: They all had the same Camshaft and Valve Train Components.

Note; The 4-Barrel Engines all had the same #3919803 Cast Iron Intake Manifold.

Note: The 327/300 HP {L75} Corvette Engine, had a better flowing Exhaust System.
 
Frank,

I'm still waiting for the 'spec sheet' that Product Planning had proposed for the
'318 Commando' in the 1968 Valiant.

Ad/Marketing was something like 'Budget Performance for the Business Coupe',
for the Valiant-S, which the 'S' was for either 'Sport' or 'Sprint' when equipped
with the Performance/Handling Package.
----------------------------------------------------------------------------------------
On the 1968 Ford 302

302/210 HP '2V'
Compression-Ratio...... 9.0-1
Pistons...................... Dish-type
Cylinder Heads.......... 59.90 CC {1.78" Intake / 1.457" Exhaust}
Carburetor................ Autolite 2V {287 CFM}

302/230 HP '4V'
Compression Ratio..... 10.0-1
Pistons..................... Dish-Type
Cylinder Heads.......... 49.50 CC {1.78" Intake / 1.457" Exhaust}
Carburetor................Autolite #4300 4MV {480 CFM}

Note; Same Camshaft and Valve-Train.

Note; Difference between the 302/210 HP and 302/230 HP, was the
'4V' Carburetor, 4-Barrel Cast Iron Intake Manifold, 'smaller' Combustion
Chamber Cylinder Heads, and Dual-Exhaust.
 
Frankie,

NHRA re-factored all these engines.

Mopars Factory HP................NHRA HP
* 273/190 HP........................162 HP
* 273/235 HP........................210 HP
* 318/230 HP........................185 HP

Chevrolet Factory HP.............NHRA HP
* 327/210 HP........................210 HP
* 327/250 HP........................245 HP
* 327/275 HP........................275 HP
* 327/300 HP........................295 HP

Ford Factory HP...................NHRA HP
* 302/210 HP.......................200 HP
* 302/230 HP.......................225 HP
 
Yes,

This is a 1967 Valiant '273 Commando', but it could have been a 1968 Valiant '318 Commando'
if Mopar wasn't afraid to put it in 318 4-Barrel engine.

A 'performance business coupe' or 'Junior Econo Performance Car'.

file.php
 
Frank,

1968 Valiant 'Specification Sheet'

The 318/230 HP with a 4-Speed could be had with the 'optional' 3.91 Gears with Sure-Grip.

68-11.jpg
 
69 Cuda 440 said:
In 1968,

Mopar had the 340 'High Performance' for the Barracuda.

Advertised at 340/275 HP, it was quickly factored and rightfully so
by the NHRA to 310 HP.

On the 'Junior-Engine' side, was an over-rated 318/230 HP {2-Barrel}
with a woefully under-sized Carter BBD Carburetor.

The NHRA corrected this 'wildly' rated engine back to down to it's
logical rating of 195 HP.

That left a gap of 115 Horsepower between the 340 'Mini-Hercules' and
the low-revving but durable 318.

Product Planning, left with a 'gaping hole' for a Junior Performance Package,
almost pulled the trigger on a '318 Commando', for the 1968 Valiant.
Click to expand...


Some of the numbers don't match up, if I'm reading this correctly.


The 318 was rated at 230 HP.

NHRA struck it down to 195 HP.


Where did they get the 115 HP difference figure from? My math comes up as 35 HP.

And if compared to the 275 HP 340, that's 80 HP different. It doesn't add up to me... :scratch:


However, it's interesting that they were going to do a 318 with a 4 bbl and dual exhaust. Too bad they didn't do that from the factory. Would it have had a cast or forged crank? Windage tray? :thumblef:
 
340@275 hp factored to 310 hp
318@230 hp factored to 195 hp
____________equals____115 hp

That's where the 115 hp comes from. With Mopar making a 273-2v, 318-2v, and a 340-4v in 1968, I don't see any good reason from a marketing perspective. Would it be useful from a class racing perspective?
 
Correct 2-Darts

NHRA ---------

318/230 HP refactored down {-35 HP} to 195 HP

340/275 HP refactored up {+35 HP} to 310 HP

Note; {115 HP Difference}
----------------------------------------------------------------------------------------------------

On the 1968 '318 Commando'

Chrysler Technician {Jerry Gross} had a 1968 Valiant 318/230 HP {2-Barrel} 4-Speed
with 3.91 Gears and Sure-Grip, with the Heavy-Duty 6-Leaf Rear-Springs and E70 x 14"
Red-Streak Tires and 14" x 5.5" Wheels off a 1968 Barracuda 340.

This was a 'Test Car' {Irwindale Raceway, January 1968}

The Valiant had a standard 318 Engine with Flat-Top Pistons, but the 1968 Cylinder Heads were swapped out
for a set of 1967 #2658920 {273 Commando} 'closed chamber' units.

Note; They were equipped with the 'stiffer' '273 Commando' Valve Springs {93 lbs. Valve-Closed ~ #208 lbs. Valve-Open}

Note; It was never stated whether the Cylinder Heads were milled to {57.3 CC's} or had
a 3-Angle Valve Job {which I'm assuming they did}.

The 'stock' 318 camshaft was replaced with a Chrysler Marine LM-318 Hydraulic Camshaft
{.420" Intake / .435" Exhaust ~ 254*/260* Duration ~ 38* Overlap}.

The 2-Barrel Intake was swapped out for a Chrysler Marine LM-318 Single-Plane 4-Barrel,
which had 1 11/16" throttle bore openings {Free-Flowing Intake}.

Carburetor was a Carter AFB #3447 {600 CFM} unit with 1 7/16" Primary and 1 11/16" Secondary.

The single-pipe exhaust system was swapped out for a 340 Dual-Exhaust System, including Exhaust Manifolds.
 
January 1968 'Performance Test @ Irwindale Raceway'

1968 Valiant '318 Commando' 4-Speed, w/3.91 Gears w/Sure-Grip

Driver - Jerry Gross {Chrysler Technician}

15.55's @ 88 MPH
 
You guys have almost convinced me to build a "what if" car like the 72 Charger R/T with the adjustable go wing and fang graphics.

...and now I have a target time to beat.

I've recently re-evaluated the 67-69 Valiant body, after seeing a large number of them at South Georgia Motorsports Park.

Light and good rear wheel clearance (not as good as Duster or 67-69 Barracuda, but better than Dart). Good combo.

Now to find one...

There was a clean slant six car, disassembled, for sale for 3K.

I also saw it as Sumter Swap meet. was generating a lot of interest at both places.
 
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