1967 ~ Barracuda 383-S and Dart GTS-383 ~ 280 HP 'How can this be.'

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69 Cuda 440

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1967

The 383 4-Barrel {383/325 HP} when installed in the Barracuda or Dart GTS
was suspiciously rated at 280 Horsepower by Plymouth and Dodge.

While it was obvious that the Dual Exhaust System, primarily on the left {driver's}
side was restricted, did it effect the 383's Horsepower rating by a 'whopping'
45 HP when compared to the same 383/325 HP 4-Barrel in a Mopar B-Body car.
 
Are you talking the same year b-body (67) or the 68 and later models?
 
I thinks they used a smller carb and the exhaust was really restrictive. We're the numbers correct back then


NO


Would you trust these numbers?

My brothers 69 GTS 383 auto 3.91 gear, was powerful and fast, never had it on the track but he took it to a guy to tune it and then took the guy a ride. Getting on the interstate the guy told him he didn't want to ride in the car again.

Was the numbers correct or a way around the small body big motor numbers game? But that said, a well running 340 would keep up or spank a big block due the weight difference. So was a 340 really 275 HP? In 68 NHRA put a HP number on the 340 at 315 instead of the advertised 275.
 
1967

Both the 383/325 HP 'B-Body' 383 {4-Barrel} and 383/280 HP 'A-Body' {4-Barrel}
had identical engine components.

Piston ................... 10.0 -1 Compression
Cylinder Heads ...... #2406516 {2.08" Intake and 1.60" Exhaust}
Camshaft 'Hyraulic' .. .425"/.437" Lift ~ 256*/260* Duration ~ 32* Overlap
Intake ................... #301-666-968 {Low-Rise Dual-Plane}
Carburetors .......... Carter AFB {#4298S M/T and #4299S A/T} = Rated @ 575 CFM's

1967 '383' 4-Barrel Ratings

A-Body
* 280 HP @ 4200 RPM's
* 400 Ft/Lbs. of Torque @ 2400 RPM's

B-Body
* 325 HP @ 4800 RPM's
* 425 Ft/Lbs. of Torque @ 2800 RPM's
 
The heads used on the 383 in those years although a closed chamber style design had a small exhaust valve, this also contributed to the lower 280HP rating along with small AFB carb, cam, low efficiency intake/exhaust design . Actually and I could be wrong... I believe the Dart and Barracuda did not have the HP stamped motors installed, just plain 4 Barrel carbed engines. My 67 383 auto car does not have a HP stamping. Very straight forward approach, I guess Chrysler was in a hurry to get these cars out the door. 1/2 year, mid year availability also says a lot on the development. In later years the cars and the engines became more refined.
 
Chrysler

Admitted in several Car Performance Magazine articles that they 'slightly'
over-rated the '383' {4-Barrel} for advertising purposes.

But they were called on the carpet by several publications, when Dyno-Tests
were performed in 1964 by 'independent' testing groups, and the Horsepower numbers were topping off in the 280 HP range at 4800 RPM's.

The reports were >

"Stating 'slightly' is one thing, but over-exaggerating by nearly 45 Horsepower is something else completely."

Still, Chrysler went on advertising the '383' at 325 HP
 
I had a 67 cuda, stock 383 4 speed. I had bunches of 69 roadrunners with stock 383 4 speed and auto. I never could justify the expense of being a racer, but I do know I always loved the 383 cars, even more than 440 and 440 six pack cars.
when the roadrunner came out with the same head as the 440, mopar played that up, to sell cars and that they did. lets face it, the numbers game of hp ratings, jack it up to sell cars, lower it to try to cheat the NRHA people.
I personally just measure everything of these old cars with the seat of my pants, that the fun factor. if I like t drive it, like its looks, like whatever power it has and I like it, then that's what matters to me.
 
My dad used to go "GTO Hunting" with his 67 Barracuda 383-S fastback 4 speed. :D

He would get them 3 out of 3 lights, then they would turn at the next light after finding out they couldn't beat him. :violent1:

After 3-4 weeks, the GTO's found another route around town after getting shut down by dad in his Barracuda.... :glasses7:

They were expecting it to be a 273, they didn't pay attention to the 383 emblem on the fender.... Until AFTER the race.... LOL! :banghead:
 
1967 Plymouth

The 'Inside Skinny'

Chrysler purposely 'low-rated' the 383 in the 1967 Plymouth Barracuda and Dodge Dart GTS to get these A-Body 'Big-Blocks' into a lower NHRA Class for 1967.

With a 280 HP rating, both the Barracuda 'Fastback' and Dart GTS 'Hardtop' would slide into the 'new' 1967 NHRA D/Stock Class, where they would have an
excellent chance to dominate, which would also help Dealership demand and 'sales'.

!967 NHRA Class
D/Stock .......... 11.30 to 11.88 Wt/HP

Make ................. Shipping Weight ................. Weight-to-Horsepower
Barracuda ............... #3202 lbs ............................ 11.44 Wt/HP
Dart GTS ................ #3208 lbs. ........................... 11.48 Wt/HP

At the time, the D/SA Class National Record was a 'soft' 13.54
and was easy attainable with a '727' Torque-Flite backed '383'
in a race-prepped A-Body.

But, a funny thing happened on the way to the NHRA for the 1967 season.
 
Have you ever looked at the cast iron manifolds on those A-body motors? Especially the drivers side. Its a wonder they made 280. Ditch em for headers and hello 325plus!

And dont overlook the torque; 400/2400 rating versus the 340s what 340/3200? Are you kidding? 400/2400! Thats fun.
 
Here's what Hemmings had to say.

The task of fitting an A-body Mopar with a 383 included more than just shoehorning the big-block engine into the compact chassis, though that feat required some modifications to the unit-body's K-frame to accommodate the larger block. In order to fit in the smaller chassis, the exhaust manifolds had to be redesigned to fit inside the fender wells and clear the steering shaft on the driver's side and the torsion bar on the right side.

But Chrysler engineering re-worked the engine beyond the simple cast-iron jujitsu required to fit the more restrictive manifolds. The engineers spec'ed a similar Carter AFB carburetor as found on the bigger cars, but fitted one with a slightly reduced capacity. The '67 A-body 383's AFB was rated a 525 CFM, versus the B-body's 575 CFM. Cylinder heads with smaller exhaust valves and a milder cam matched the exhaust manifold changes, and the carburetor was calibrated for the slightly lower output engine. The end result was a drop in output from the Charger's 325 hp and 425 lb.ft. of torque to 280 hp and 400 lb.ft. in the Dart GT. Though in a car weighing several hundred pounds less than the Charger, the Dart GT's 383 gave plenty of go power.

The lack of power steering had nothing to do with drag strip intentions and reducing parasitic losses. It was simply that the modified exhaust manifold did not leave enough space for a power-steering pump, giving all '67 383 Dart GT owners a workout navigating parking lots. Make that a sweaty workout, as the installation of the 383 also obviated the availability of air-conditioning.
 
1967 NHRA Season

December 1966

The NHRA was 'not tricked' by Mopar at the end of 1966 at the winter meetings
in December 1966 in Detroit.

The 383/280 HP in the 1967 Plymouth Barracuda {available for December 1966}
was 're-factored' to 300 HP. by the NHRA.

Now the 1967 Barracuda 'Fastback' at #3202 lbs. had a Weight-to-Horsepower
factor of ....... 10.67 Wt/HP, instead of a previous expected {hoped for} 11.44 Wt/HP.

Now the Barracuda 383-S would be classed one-slot lower to 'C/Stock'
for 1967

* C/S and C/SA ......... 10.60 to 11.29 Wt/HP

This threw a 'cog-in-the-wheel' at Plymouth Racing.

1965 and 1966 Mopar Factory-backed Stocker Champion - Dave Kempton was in the middle of putting together a 1967 Barracuda 383-S for D/SA.

When the NHRA re-factored the 383/280 HP to 300 HP, Dave 'pulled-the-plug' on
his Barracuda and did not take it to the 1967 NHRA Winternationals.
 
69 Cuda 440 said:
1967 NHRA Season

December 1966

The NHRA was 'not tricked' by Mopar at the end of 1966 at the winter meetings
in December 1966 in Detroit.

The 383/280 HP in the 1967 Plymouth Barracuda {available for December 1966}
was 're-factored' to 300 HP. by the NHRA.

Now the 1967 Barracuda 'Fastback' at #3202 lbs. had a Weight-to-Horsepower
factor of ....... 10.67 Wt/HP, instead of a previous expected {hoped for} 11.44 Wt/HP.

Now the Barracuda 383-S would be classed one-slot lower to 'C/Stock'
for 1967

* C/S and C/SA ......... 10.60 to 11.29 Wt/HP

This threw a 'cog-in-the-wheel' at Plymouth Racing.

1965 and 1966 Mopar Factory-backed Stocker Champion - Dave Kempton was in the middle of putting together a 1967 Barracuda 383-S for D/SA.

When the NHRA re-factored the 383/280 HP to 300 HP, Dave 'pulled-the-plug' on
his Barracuda and did not take it to the 1967 NHRA Winternationals.
Click to expand...

This... ChryCo was trying to buy the lower HP to weight classes, a break. NHRA(no hot rods allowed..) ,never liked Chrysler's aggressiveness in drag racing technology.
 
A-Body-Bomber

Back then, the NHRA was out to protect the 'Junior Stock Classes' for General Motors.

NHRA National Records ..... January 1967

* C/S ......... 12.78
* D/S ......... 12.85

* C/SA ........ 13.11
* D/SA ........ 13.54

You can see why Dave Kempton and Plymouth Racing wanted the 1967 Barracuda
383-S out there at the 1967 NHRA Winternationals classed in D/SA.

If Dave was allowed to run that 67' Barracuda in D/SA, he would have captured the
Stock Championship.

After the NHRA re-factoring in December 1966, the Barracuda was shipped back to
the factory.

Dave never ran it. A few years later he stated that he had it dialed in for 13.30's @ 107 MPH.
 
69 Cuda 440 said:
A-Body-Bomber

Back then, the NHRA was out to protect the 'Junior Stock Classes' for General Motors.

NHRA National Records ..... January 1967

* C/S ......... 12.78
* D/S ......... 12.85

* C/SA ........ 13.11
* D/SA ........ 13.54

You can see why Dave Kempton and Plymouth Racing wanted the 1967 Barracuda
383-S out there at the 1967 NHRA Winternationals classed in D/SA.

If Dave was allowed to run that 67' Barracuda in D/SA, he would have captured the
Stock Championship.

After the NHRA re-factoring in December 1966, the Barracuda was shipped back to
the factory.

Dave never ran it. A few years later he stated that he had it dialed in for 13.30's @ 107 MPH.
Click to expand...

Sounds right,thanks for the info 69...
 
Fudging the Horsepower Numbers for 1967

Chevrolet >
Re-factored the 1966 'L-79' 327/350 HP to {325 HP} for 1967
in the Chevy 'II' Nova SS cars.

This dropped the Weight-to-Horsepower factor from {8.58 Wt/HP} to a
now {9.23 Wt/HP}

The 'new' HP Factor permitted the 1967 Chevy 'II' 327/325 HP cars to
run in A/Stock {8.70 to 9.49 Wt/HP} for 1967.

The 1966 Chevy 'II' 327/350 HP cars could only run in Super/Stock for
1967.

Ford and Mercury >
Re-factored the 1966 'S-Code' 390/335 HP to {320 HP} for 1967
in the Ford Fairlane GT and GTA.

Pontiac >
Took the 400/350 HP GTO engine, and dropped it in their new Firebird, and rated it at {325 HP}.

Also, they popped the 400/360 HP 'Ram Air' GTO engine in the Firebird, and rated it
at {335 HP}.

Note; Pontiac adjusted the linkage for the Rochester Carburetor on the Firebird
400 engines to restrict the Secondaries from fully opening.

Note; That was the 'only' difference between the GTO and Firebird engines.
 
69 Cuda 440 said:
Fudging the Horsepower Numbers for 1967

Chevrolet >
Re-factored the 1966 'L-79' 327/350 HP to {325 HP} for 1967

Ford and Mercury >
Re-factored the 1966 'S-Code' 390/335 HP to {320 HP} for 1967.

Pontiac >
Took the 400/350 HP GTO engine, and dropped it in their new Firebird, and rated it at {325 HP}.

Also, they popped the 400/360 HP 'Ram Air' GTO engine in the Firebird, and rated it
at {335 HP}.

Note; Pontiac adjusted the linkage for the Rochester Carburetor on the Firebird
400 engines to restrict the Secondaries from fully opening.

Note; That was the 'only' difference between the GTO and Firebird engines.
Click to expand...

:eek:ops: no hard facts here, and different year. In 1968, I bought a 68 form. S barracuda fastback at tink wilkersons chry. ply. in Tulsa ok. gave $3256 for it out the door. was a dark met. green(don't know the color code), white interior, bucket seat console auto. in the floor. papers said it was the roadrunners engine w/ a redesigned drivers side exhaust manifold, cutting the h.p. to 330 from the 335 for the r.r. limited slip . 8 3/4-gear unknown. car was almost uncontrollable, handled great. taking it back to the a.f. base, going thru the mountains in ark., I out ran a (so called hugger) Camaro and a volkswagon, the volkswagon was between me and the Camaro all the way. think this might have been an unusual combination. God only knows how much I wish I had kept that car! remember part of the particulars" was extra heavy duty torsion bars and sway bars. how rare was that thing ? also the exhaust was very load for the times, always got a look from the cops.
 
1967

Interesting how in 1967 the NHRA allowed Ford to slide the 1966 390/335 HP 'S-Code'
down to 320 HP, with the same exact engine components.

In 1966 the Mercury Cyclone GT {390/335 HP} weighed in at #3315 lbs.
> 3315 lbs. ~ 335 HP = 9.89 Wt/HP

In 1967, the Mercury Cyclone GT {390/320 HP} weighed in at #3393 lbs.
> 3393 lbs. ~ 320 HP = 10.60 Wt/HP

1967 NHRA Class
> D/S and D/SA ....... 10.60 to 11.29 WT/HP

~ What a Coincidence ~
 
famous bob said:
:eek:ops: no hard facts here, and different year. In 1968, I bought a 68 form. S barracuda fastback at tink wilkersons chry. ply. in Tulsa ok. gave $3256 for it out the door. was a dark met. green(don't know the color code), white interior, bucket seat console auto. in the floor. papers said it was the roadrunners engine w/ a redesigned drivers side exhaust manifold, cutting the h.p. to 330 from the 335 for the r.r. limited slip . 8 3/4-gear unknown. car was almost uncontrollable, handled great. taking it back to the a.f. base, going thru the mountains in ark., I out ran a (so called hugger) Camaro and a volkswagon, the volkswagon was between me and the Camaro all the way. think this might have been an unusual combination. God only knows how much I wish I had kept that car! remember part of the particulars" was extra heavy duty torsion bars and sway bars. how rare was that thing ? also the exhaust was very load for the times, always got a look from the cops.
Click to expand...

Famous Bob

A-Body 383 Horsepower Ratings

* Year ....... Factory Advertised ..... NHRA {Back in the Day}
* 1967 .............. 280 HP ................... 300 HP
* 1968 .............. 300 HP ................... 310 HP
* 1969 .............. 330 HP ................... 330 HP
----------------------------------------------------------------------------------

B-Body 383 Horsepower Ratings

* Year ....... Factory Advertised ..... NHRA {Back in the Day}
* 1967 ............... 325 HP ................... 325 HP
* 1968 ............... 330 HP ................... 330 HP
* 1968 ............... 335 HP ................... 335 HP {Road Runner and Super Bee}
* 1969 ............... 330 HP ................... 330 HP
* 1969 ............... 335 HP ................... 335 HP {Road Runner and Super Bee}
 
Frito

Lots of funny business in the Horsepower Ratings for 1967, especially when getting
the cars classed in the NHRA

1967 Camaro Z-28 {302/290 HP}

Shipping Weight .......... #2955 lbs. ~ 290 HP = 10.18 Wt/HP

This put the Camaro in B/Stock {9.50 to 10.59 Wt/HP} for 1967,
where it was completely dominant.

That didn't last long, as for 1968, the 302/290 HP in the 1967 Z-28 was
re-factored up {+25 HP} to 315 HP in 'Stock Class'.

1968 Horsepower Factor

#2955 lbs. ~ 315 HP = 9.38 Wt/HP
 
Just a numbers game back then I'm sure. Everybody factored weight to horsepower back then.
 
toolmanmike said:
Just a numbers game back then I'm sure. Everybody factored weight to horsepower back then.
Click to expand...

The 'Junior Stocker Wars'

Really started at the 1966 NHRA Winternationals, when Mercury showed up
with '8' 1966 Mercury Cyclone's {390/335 HP} classed in C/S and C/SA.

They were 'factory-prepared' and shoe'd by the best Ford and Mercury
Racers {ie; A/FX, Super Stock and AWB} available.
 
I had a 1968 GTS 383 4spd. I bought it from an older gentleman at work and asked him why he purchase it. He went to Prince Dodge in Inglewood, CA. He was 60 years old when I bought it from him(with an inch of dust on it in his garage). He told me he test drove a 68 Hemi Dart at the same dealer around the block and that he had to apply to brakes throughout the whole test drive. When I asked him why he picked the 68 383 Dart he said he drove all big block offerings from all manufacturers. He chose the 383 GTS. White. 4spd. Stripe delete. Dog Dish hub caps. He was so essentric that he installed switches to over ride the reverse backup lights. He was an Aerospace engineer so he was looking for power to rate ratio. I guess the early offering 1969 Chevy Nova 396 didn't do it for him. That 383 Dart was fast. With its stock exhaust manifolds. So I bought the car from him. I paid $1200 in 1986. I sold it in 1988 for a 1970 Challenger T/A. Which I sold in 1994.
Now I'm depressed.
 
1967 A-Body 383/280 HP 'Myth'

It was thought that the Carter AFB was a 'smallish' 525 CFM unit, specifically
designed for air-flow and fuel restriction.

Not so.

The Carter AFB Carburetors #4298S {M/T} and #4299S {A/T} were
advertised at 575 CFM's by Carter.

These AFB units were the same exact Carter AFB's found on the B-Body
383/325 HP 4-Barrel Engines.

* Primary ....... 1 7/16" {1.437"} ...... Venturi > 1 3/16" {1.186"}
* Secondary ... 1 9/16" {1.563"} ...... Venturi > 1 5/16" {1.313"}

* Primary Jets ...... .089" {M/T} ...... .089" {A/T}
* Secondary Jets .. .0695" {M/T} ..... .068" {A/T}

* Metering Rod ...... 16-404 {.063" Economy ~ .051" Power}
 
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