Match Race 1972 ~ 'Duster 340 vs 'GTO 400'

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1972 Duck-Tail Spoiler

* The book says, that only '3' made it on the 1972 GTO as it rolled off the assembly line.

* They were supposed to be 'standard' on the 1972 GTO.

* During the 'first' trial-test run off the assembly line, the Duck-Tail ripped off the GTO trunk deck-lid
at 75 MPH.

* Pontiac said the proto-type mold broke, so they couldn't produce the Duck-Tail unit anymore.

* Can you say......Insurance Liability.

* A 'new' Rear-Wing Spoiler was designed, and was now offered as an 'option'.


* Freakin' Wings................should only be eaten.
 
69 Cuda 440 said:
Freakin' Wings................
Click to expand...

LOL...


Getting back to the Duster, in the muscle car realm, i've driven quite a few "stock" low compression GM's and a few Fords, but the only Mopar I recall was a 73' Charger 440 auto. It had a very smooth power curve up to about 5k, i'm guessing, no tach, but nothing to write home about. I've never driven a 72'/73' 340 car, although I rode in a 73' 340 Dart Sport a few times. I'm just curious about how they felt compared to the earlier cars? All I can do now is look at the numbers, but I'd love to have felt what they were like on the street. I'm sure a little tickle to the TQ and timing made a big difference.
 
O-M-R

My sister bought a new 1973 Dart Sport 340. Automatic, w/Air Conditioning.
It was decent, but not a Street Terror. Probably would have run in the 15.30 range.

One of my fathers Machine Shop employee's had a 1973 'Cuda 340, 4-Speed.
Not really a fast car, but an adequate Street Performer for the low-octane era.

Note; It sounded better than it ran.......
 
69 Cuda 440 said:
O-M-R

My sister bought a new 1973 Dart Sport 340. Automatic, w/Air Conditioning.
It was decent, but not a Street Terror. Probably would have run in the 15.30 range.

One of my fathers Machine Shop employee's had a 1973 'Cuda 340, 4-Speed.
Not really a fast car, but an adequate Street Performer for the low-octane era.

Note; It sounded better than it ran.......
Click to expand...

Around 1975, my buddy with his 70' Duster 340, 13.80's car, got called out by a guy with a stock 73' 340 Challenger for $100 bucks, and he insisted on it...lol. Although a beautiful car, he thought it was the cats a$$. Needless to say, by the 1/8th mile, there was about 6+ car lengths between them.....lol. Easy money :D.
 
I also wonder what some of you guys take is on the tests from back in the day? I know that the drivers experience and conditions played a huge role, but how much stock would you put into how "new" the tested cars were? Meaning were they broken in, loosed up?

After a huge amount of prodding to buy a new 74' Dart Sport 360, a friends Mom settled on a 74' 400" 2dr Malibu Classic. Biggest stone on the planet...lol. He took it to the track when it had just 600 miles on it, and went a blistering 17.70 @ 73mph. About a year and a half later with 14k miles on it, he brought it out again just for grins and it went 17.20's @ 78mph :banghead:. Absolutely nothing was modified other then a dealer tune up. Granted it still couldn't get out of it's own way, but how can you justify that kind of pickup other then the engine just "loosened" up? We were stumped!

One of the reasons it was so slow was that the 400 2bbl was pretty much dead past 4300/4500 rpms. Add to that, while letting the trans shift on it's own, the governor didn't let it shift until at least 5k, and the top of each gear was flat at best.:D
 
Google "Joe Oldham muscle car testing". He was one of the better magazine prep/drivers. He actually wrote a book dedicated just to your question.LOTS of tweaking,all makes and models.
 
Magazine Performance Tests

Up and Down.......

* Some Magazines took a car right of the Dealer Lot, and ran them 'as is'
* Some got the 'Press Test Car'
* Some got a 'tweaked' car from the Corporate or Regional Office
* Some got a tired 'Dealer Test Car'

Example, from 1972 Magazine Tests

1972 Pontiac GTO 455/300 HP 'HO' ~ 4-Speed ~ 3.55 Gears 'Safe-T-Track'

* Motor Trend................ 15.40 @ 92.2 MPH
* Motor City News.......... 15.14 @ 93.6 MPH
* Performance Review.....14.87 @ 95.0 MPH
* Car and Driver............ 14.77 @ 96.0 MPH
* Pontiac Magazine........ 14.60 @ 95.2 MPH

In 1981, 'Motors Magazine' found a 1972 GTO 455/300 HP 'HO' 4-Speed car with 3.55 Gears.

They restored it to stock specifications, including using a properly ground Camshaft, exact tolerances,
a NHRA Blueprinted Valve Job, 'Zero Deck Block', milled Cylinder Heads {to NHRA minimum specifications},
matched gasket/ports, Balanced Internals, properly adjusted Rochester Spread-Bore, and a Professionally
set Distributor.

With the Air-Cleaner top removed, and all the accessory belts loosened.

Performance Results....... 14.11 @ 98.7 MPH {Best Time}
 
Abodybomber said:
Google "Joe Oldham muscle car testing". He was one of the better magazine prep/drivers. He actually wrote a book dedicated just to your question.LOTS of tweaking,all makes and models.
Click to expand...

Man, I haven't heard Oldham's name mentioned in years. Thanks for the tip on the book. That's gotta be some great reading.
 
Mopar would sometimes send their Press Test cars to Rockville Centre Dodge
in Southern Nassau County, Long Island.

They would get the 'full' secret treatment before a Magazine Performance Test.

Including a Cylinder Head 'Mill Job' of .030"
 
My brother Dave had a brand new 1972 Demon 340 back in the day, which was basically the same car as a Duster. It had a 340, auto., AC, PS, etc. It ran high-14 second times at Union Grove Dragstrip in stock trim. A good friend of ours had a new GTO/LeMans with the low-perf. 400 engine, auto., AC, etc. That car never ran better than a mid-15 second time slip. We ran them side-by-side at the strip and on the street and the GTO never beat the Demon. This is a real-world fact!
 
sr71mopar said:
Last thing the GTO saw before the rods fell out.
Click to expand...

My best friend Rick ordered a new 1972 340 Duster. It arrived in late Winter and as soon as Dragway 42 opened in the Spring we were there. It was Sherwood Green like the picture in the above post. I still have a couple pictures of the car on the strip when he ran it. It was right off the street
showroom stock and by now the car had about 5000 miles on it. The one and ONLY change from stock was it had G70-14 Goodyear Polyglas tires on the rear. (Rick was originally from Akron and always used Goodyear tires and his family always used their garages for service work)

He only made one pass, 3.23 SG and 4 speed. It ran 14.51.
 
1972 'Duster 340'

Was not regarded as a Street Terror, but for 1972 it could handle itself well against
the other 1972 Models.

Especially if you got the 3.55 Gears w/Sure-Grip.

Properly tuned, it could break into the high 14.00's - especially with the
new Electronic Ignition and the 'Air-and-Fuel Thirsty' 800 CFM Thermoquad.

If you picked the right Exterior Color, it was one sharp looking car.........

!Bin--wQB2k~$(KGrHqEH-C8Es9NdLRN3BLP+b5mQBQ~~_12.JPG
 
There is no question, Plymouth got the Duster right.
Price, performance & style!
 
1n 1972,

Several of the Mopar 'Performance Oriented Dealerships' in the Northeast offered an
'over-the-counter' dealer installed performance package for the 1972 Duster 340.

* 'Weiand' Aluminum Dual-Plane Intake Manifold {w/Spread-Bore Adaptor}
* 3.91 Gears
* Camshaft 'Hydraulic' {'Lunati' True-Grind}
* .462" / .473" Lift ~ 286* / 294* Duration ~ 60* Overlap
* Double Roller Timing Chain

* Thermoquad Carburetor {Re-calibrated with a #10-111 Kit}

Note; The 1972 Thermoquad tended to run on the 'lean side'. A larger set of Primary Jets
were installed, along with a Power-Step Metering Rod.
 
69 Cuda 440 said:
O-M-R

My sister bought a new 1973 Dart Sport 340. Automatic, w/Air Conditioning.
It was decent, but not a Street Terror. Probably would have run in the 15.30 range.

One of my fathers Machine Shop employee's had a 1973 'Cuda 340, 4-Speed.
Not really a fast car, but an adequate Street Performer for the low-octane era.

Note; It sounded better than it ran.......
Click to expand...

My wifes 72 340 sounded as stout as my 69 340.
Chyrsler also new what exhaust to put under there performance cars.
 
69 Cuda 440 said:
The NHRA bumped the 1972 Duster 340/240 HP all over the place.

NHRA..........HP...........Stock.....Super Stock
1972........ 240 HP........E/S.........SS/O
1973........ 270 HP........H/S.........SS/L
1974........ 270 HP........H/S.........SS/L
1975........ 275 HP........H/S.........SS/L
1980........ 275 HP........H/S.........SS/L
2002........ 270 HP........H/S.........SS/L
2003........ 285 HP........G/S.........SS/K
2004........ 285 HP........G/S.........SS/K
2008........ 289 HP........F/S.........SS/J
2009.........293 HP........F/S.........SS/J
2010.........293 HP....... F/S.........SS/J
2011.........299 HP....... F/S.........SS/J
Click to expand...

Here is a 1972 'Duster 340' in 1974 classed in SS/L {11.50 to 11.99 Wt/Hp}


file.php
 
The cam lobe design of a modern stocker must be crazy. They probably just about mimic a mild "roller".....lol. I'd like to know the life span on some of the Chevys and Fords? At least Ma provided a .904 lifter. Then again, if your not trying to qualify up top or on some record runs, I guess there's no reason to push the limit.
 
I understand why the factory fudged downward on HP ratings.
But why do that with compression ratio?
 
1972 'Duster 340'

Magazine Performance Tests

Range
4-Speed ~ 3.23 Gears......... 14.80 to 15.15
Automatic ~ 3.23 Gears...... 15.05 to 15.30

4-Speed ~ 3.55 Gears......... 14.50 to 14.95
Automatic ~ 3.55 Gears...... 14.45 to 15.05



1972_page_53.jpg
Note:
 
O-M-R

On the 1972 Pontiac GTO

Available Engines
* 400/250 HP {L-78}............ 8.2 to 1
* 455/250 HP {L-75}............ 8.2 to 1
* 455/300 HP {L-55} 'HO'..... 8.4 to 1

The 400/250 HP {L-78} outran the 455/250 HP {L-75}.

The 455/250 HP {L-75} was available in an 'Automatic Only'. Back-in-the-day, this
was the Engine that the Pontiac GTO 'Gear-Heads' said to stay away from.

Big Cubes, but no Horsepower. Low-End Torque was massive though {475 Ft/Lbs. @ 3400 RPM}

The #7M5 Cylinder Heads were/are regarded as one of the poorest designed 455 Heads. Big monster
Combustion Chambers from the factory {114 CC's}, and the Exhaust Ports were poor flowing
despite the 1.77" Exhaust Valve.

If you wanted to use them, Pontiac recommended milling them {.055"} down to 101.8 CC's. to get
the Compression up to {9.22} from an anemic {8.20}.

Then work like a Mad-Man on grinding out the Exhaust Ports, and smoothing out the Intake Ports and Valve Bowls.

That's why only a few of the 455/250 HP 'L-75' GTO's exist today.........only 240 Built by Pontiac.
 
I agree with that assessment. The Pontiac D-port heads just couldn't get it done in anything other then a torque biased build, without work. The small port big Chevy heads, (not the late peanuts), even with a little less valve, would run circles around them. I never flow tested either, but just the response to a fairly big street cam, told me all I needed to know.

I love the drivetrain spec sheet. The fact that a column shift 3spd was standard vs the floor shift really surprised me. I've never seen a column shift 72' A body before?

My late grandfather that died in 1988 @ 85yrs old, refused to drive a auto trans car. And he never did! Even though he had a few early/mid 60's Impala/Belair cars with 4spds, his last "big" car was a 1972 Belair 4dr with a 350-2 and a column 3spd. Had to be more rare then most Hemi cars...lol.
 
O-M-R

1972 Pontiac 400/250 HP ~ #7K3 ~ Cylinder Heads
Intake Flow @ .450" Lift......... 201 CFM
Exhaust Flow @ .450" Lift....... 155 CFM

1972 Pontiac GTO 455/250 HP ~ #7M5 ~ Cylinder Heads
Intake Flow @ .450" Lift........ 165 CFM
Exhaust Flow @ .450" Lift...... 108 CFM

Same Valve Size 2.11" Intake and 1.77" Exhaust

The 'Pontiac Book' states that in 1972, the 400/250 HP with a TH-400 Automatic was non-performing
in the Torque Department, so Pontiac put in a few 455/250 HP {Code L-75} engines in a limited amount
of {Automatic 'only'} GTO's, which provided for massive amounts of low-end Torque.

455/250 HP {L-75}........ 475 Ft/Lbs. @ 3400 RPM's
versus
400/250 HP {L-78}....... 325 Ft/Lbs. @ 3200 RPM's

* Standard Gears.... 3.07 {Squealing Tire Smokers}
* Optional Gears..... 3.31
 
What a difference! That 7M5 barely flows enough for a 326.....lol. Almost like they decided to just skip one of the machining operations.
 
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