With Automatic ........... Advantage for Pontiac GTO ..... {-156 lbs.}
With 4-Speed ............. Advantage for Pontiac GTO ..... {-267 lbs.}
'1967 Holiday Race' ~ Plymouth GTX 440 vs. Pontiac GTO 400 'Ram Air'
- Thread starter 69 Cuda 440
- Start date
-
With Automatic ........... Advantage for Pontiac GTO ..... {-156 lbs.}
With 4-Speed ............. Advantage for Pontiac GTO ..... {-267 lbs.}
1967 Pontiac GTO 400/360 HP 'Ram Air'
Early Production Heads ....... #670
Late Production Heads ........ #97
Which included;
* Modified Valve Spring Seat Cuts ~ To accept taller Dual Valve Springs
* Polished Valves
Where The Rubber Meets The Road
1967 Plymouth GTX
7.75 x 14"
Goodyear 'Red Streak'
Diameter ..... 26.61"
Width ........... 5.27"
1967 Pontiac GTO
F70 x 14"
Firestone 'Red Line'
Diameter .... 26.45"
Width .......... 6.55"
1967 Plymouth GTX
7.75 x 14"
Goodyear 'Red Streak'
Diameter ..... 26.61"
Width ........... 5.27"
1967 Pontiac GTO
F70 x 14"
Firestone 'Red Line'
Diameter .... 26.45"
Width .......... 6.55"
Johnny Rocco
Front-to-Rear Weight Distribution
1967 Plymouth GTX 440/375 HP 'Super Commando' {Automatic}
Curb Weight = #3754 lbs.
Front; #2140 lbs. {57%} ~ Rear; 1614 lbs. {43%}
1967 Plymouth GTX 440/375 HP 'Super Commando' {4-Speed}
Curb Weight = #3865 lbs.
Front #2165 {56%} ~ Rear; #1700 lbs. {44%}
_____________________________________________________________
1967 Pontiac GTO 400/360 HP 'Ram Air' {Automatic and/or 4-Speed}
Curb Weight = #3598 lbs.
Front = #2051 lbs. {57%} ~ Rear = #1547 lbs. {43%}
Front-to-Rear Weight Distribution
1967 Plymouth GTX 440/375 HP 'Super Commando' {Automatic}
Curb Weight = #3754 lbs.
Front; #2140 lbs. {57%} ~ Rear; 1614 lbs. {43%}
1967 Plymouth GTX 440/375 HP 'Super Commando' {4-Speed}
Curb Weight = #3865 lbs.
Front #2165 {56%} ~ Rear; #1700 lbs. {44%}
_____________________________________________________________
1967 Pontiac GTO 400/360 HP 'Ram Air' {Automatic and/or 4-Speed}
Curb Weight = #3598 lbs.
Front = #2051 lbs. {57%} ~ Rear = #1547 lbs. {43%}
95teetee
Well-Known Member
'flew' being a relative term lol.
fratzog lover
Well-Known Member
Wallace racing (Pontiac) cylinder head test. Conclusions:
I have no doubt that these figures are going to cause some conster*nation among a number of HPP's readers. The "I told you my head is better than yours" contingent should have a field day.
Before readers jump to conclu*sions based on airflow numbers alone, however, they must take into account all the other factors that compose a total engine combination. A well-set-up 400-cid engine with big-valve No.16 or No.48 D-port heads is going to run just as well as another engine with Ram Air IV heads, if the tuner doesn't have enough cam and gearing to utilize the higher-lift airflow
I'm sure our readers are quite capable of drawing their own con*clusions with respect to some of these heads. I cannot resist the temptation, however, to list a few of my own opinions (see “Pete's Picks"). Whether you agree with these assess*ments or not, I would imagine that most Pontiac die-hards will find the numbers researched to be of great interest.
We'll get into the complexities and complications of porting various Pontiac heads in the near future. I promise you that the surprises will be many.
Best performance head 1970 Ram Air IV
Best intake port 1969-70 Ram Air V
Best exhaust port 1 968 1/2 Ram Air II
Best D-port head No.16, No.48, No.12 (tie)
Best low-compression D-port head No.96(1971)
Best low-compression post-1972 head No. 6X
Best balanced head (exhaust to intake) 1963 421 SD
Best low-lift (under .400) head 1967 No.670
Worst exhaust-to-intake port ratio 1969-70 Ram Air V
Worst intake-to exhaust ratio 1968 1/2 Ram Air II
Biggest surprise Intake port, No.17 350 head
Biggest disappointment 1969-70 RA V, 1973-74 455 SD (tie)
Biggest "sleeper" 1975 No. 5C
Most undercammed 1963 SD, 1971 455 HO, 1973-74 455 SD (tie)
Most underexhausted 1964 GTO (No.9770716)
Most potential for porting 1973-74 455 SD, 1968 1/2 RA II (tie)
A good low lift head.
I have no doubt that these figures are going to cause some conster*nation among a number of HPP's readers. The "I told you my head is better than yours" contingent should have a field day.
Before readers jump to conclu*sions based on airflow numbers alone, however, they must take into account all the other factors that compose a total engine combination. A well-set-up 400-cid engine with big-valve No.16 or No.48 D-port heads is going to run just as well as another engine with Ram Air IV heads, if the tuner doesn't have enough cam and gearing to utilize the higher-lift airflow
I'm sure our readers are quite capable of drawing their own con*clusions with respect to some of these heads. I cannot resist the temptation, however, to list a few of my own opinions (see “Pete's Picks"). Whether you agree with these assess*ments or not, I would imagine that most Pontiac die-hards will find the numbers researched to be of great interest.
We'll get into the complexities and complications of porting various Pontiac heads in the near future. I promise you that the surprises will be many.
Best performance head 1970 Ram Air IV
Best intake port 1969-70 Ram Air V
Best exhaust port 1 968 1/2 Ram Air II
Best D-port head No.16, No.48, No.12 (tie)
Best low-compression D-port head No.96(1971)
Best low-compression post-1972 head No. 6X
Best balanced head (exhaust to intake) 1963 421 SD
Best low-lift (under .400) head 1967 No.670
Worst exhaust-to-intake port ratio 1969-70 Ram Air V
Worst intake-to exhaust ratio 1968 1/2 Ram Air II
Biggest surprise Intake port, No.17 350 head
Biggest disappointment 1969-70 RA V, 1973-74 455 SD (tie)
Biggest "sleeper" 1975 No. 5C
Most undercammed 1963 SD, 1971 455 HO, 1973-74 455 SD (tie)
Most underexhausted 1964 GTO (No.9770716)
Most potential for porting 1973-74 455 SD, 1968 1/2 RA II (tie)
A good low lift head.
1967 Plymouth GTX 440/375 HP 'Super Commando'
vs.
1967 Pontiac GTO 400/360 HP 'Ram Air'
Stock vs. Stock ........... 4-Speed vs. 4-Speed
Have to go with 'The Goat' here, by a solid win.
Remember, the GTX was equipped with 3.54 Gears in the Dana Rear. Though, thru a
'Special Order Only', you could finagle 4.10 Gears.
The Pontiac GTO came thru with 4.33 Gears {as standard equipment}.
The GTO also had the advantage of an M-21 {Close-Ratio} Transmission.
* M-21 ....... 2.20 ~ 1.64 ~ 1.28 ~ 1.00
* A-833 ...... 2.65 ~ 1.93 ~ 1.39 ~ 1.00
And, the GTO came equipped with a Hurst Shifter, while the GTX was equipped with
the 'junk-link' Inland Shifter.
The GTO also had an advantage in Tire Width, with F70 x 14"s {6.55" Width}. versus
the GTX with 7.75 x 14"s {5.50" Width}.
But the 'baggage' was the real culprit here. In 'Curb Weight', the GTX was heavier
by {+267 lbs.}. That is a lot of 'Meat'.
vs.
1967 Pontiac GTO 400/360 HP 'Ram Air'
Stock vs. Stock ........... 4-Speed vs. 4-Speed
Have to go with 'The Goat' here, by a solid win.
Remember, the GTX was equipped with 3.54 Gears in the Dana Rear. Though, thru a
'Special Order Only', you could finagle 4.10 Gears.
The Pontiac GTO came thru with 4.33 Gears {as standard equipment}.
The GTO also had the advantage of an M-21 {Close-Ratio} Transmission.
* M-21 ....... 2.20 ~ 1.64 ~ 1.28 ~ 1.00
* A-833 ...... 2.65 ~ 1.93 ~ 1.39 ~ 1.00
And, the GTO came equipped with a Hurst Shifter, while the GTX was equipped with
the 'junk-link' Inland Shifter.
The GTO also had an advantage in Tire Width, with F70 x 14"s {6.55" Width}. versus
the GTX with 7.75 x 14"s {5.50" Width}.
But the 'baggage' was the real culprit here. In 'Curb Weight', the GTX was heavier
by {+267 lbs.}. That is a lot of 'Meat'.
Yeah it's a whole nuther redneck sittin in the passenger seat with a beer in his hand.
'1967' Redneck
Minimum Weight ......... 250 lbs.
Foot Wear .................. Size 13 {S**t Kicker Boots}
Clothing ..................... Overall's
Beverage ................... Beer {A Case of Tall Boys}
8-Track Tapes ............ Merle Haggard ~ Johnny Cash ~ Waylon Jennings
Advantges
Factory Stock 4-Speed vs. 4-Speed
..................Plymouth GTX .......... Pontiac GTO
Body Style ......................................... ^
Aerodynamics .................................... ^
Horsepower ............. ^
Torque .................... ^
RPM's ................................................ ^
Weight .............................................. ^
Suspension .............. ^
Rear-End Strength .... ^
Traction ................... ^
Gears ................................................ ^
Transmission Gearing .......................... ^
Shifter ............................................... ^
Clutch ..................... ^
Exhaust ................... ^
Fresh-Air Intake .................................. ^
Tires .................................................. ^
Factory Stock 4-Speed vs. 4-Speed
..................Plymouth GTX .......... Pontiac GTO
Body Style ......................................... ^
Aerodynamics .................................... ^
Horsepower ............. ^
Torque .................... ^
RPM's ................................................ ^
Weight .............................................. ^
Suspension .............. ^
Rear-End Strength .... ^
Traction ................... ^
Gears ................................................ ^
Transmission Gearing .......................... ^
Shifter ............................................... ^
Clutch ..................... ^
Exhaust ................... ^
Fresh-Air Intake .................................. ^
Tires .................................................. ^
Get Those CFM's Flowing
1967 Pontiac GTO 400/360 HP 'Ram-Air'
4-Speed Carburetor
Rochester Quadrajet 4-MV
Part #7037263
Advertised CFM's ............ 750
Flow Rate ...................... 730
Primary ........................ 1 3/8"
Secondary .................... 2 1/4"
Venturi Sizes ................. 1.093" x AV
Main Jet Size ................ .070"
Main Rod Size ............... .038"
Spring ......................... #7037305
Secondary Jet Size ........ .136"
Secondary Rod Size ....... 'BF' #7034400 {Rich}
Tip Length .................... Short
Jet Area {Cruise} .......... 2.7143
Jet Area {W.O.T} .......... 3.3175
'Ram-Air' Effect
This Carburetor is 'specially calibrated' to work in conjunction with the 'Ram Air' {Hood Scoop} open.
1967 Pontiac GTO 400/360 HP 'Ram-Air'
4-Speed Carburetor
Rochester Quadrajet 4-MV
Part #7037263
Advertised CFM's ............ 750
Flow Rate ...................... 730
Primary ........................ 1 3/8"
Secondary .................... 2 1/4"
Venturi Sizes ................. 1.093" x AV
Main Jet Size ................ .070"
Main Rod Size ............... .038"
Spring ......................... #7037305
Secondary Jet Size ........ .136"
Secondary Rod Size ....... 'BF' #7034400 {Rich}
Tip Length .................... Short
Jet Area {Cruise} .......... 2.7143
Jet Area {W.O.T} .......... 3.3175
'Ram-Air' Effect
This Carburetor is 'specially calibrated' to work in conjunction with the 'Ram Air' {Hood Scoop} open.
Kerchang !
I'll post up all the 1967 Magazine Performance Test articles for you.
For Your Information >
Back in 1967, it was the Pontiac GTO 400/360 HP 'Ram Air' which dominated
NHRA Stock Class {B/Stock}.
They were pegging 12.60's without any problem.
The GTX 440 and R/T 440 were not dominant in B/Stock {4-Speed}.
"TOO HEAVY"
I'll post up all the 1967 Magazine Performance Test articles for you.
For Your Information >
Back in 1967, it was the Pontiac GTO 400/360 HP 'Ram Air' which dominated
NHRA Stock Class {B/Stock}.
They were pegging 12.60's without any problem.
The GTX 440 and R/T 440 were not dominant in B/Stock {4-Speed}.
"TOO HEAVY"
TheseQUOTE=fratzog lover;1971068712]Wallace racing (Pontiac) cylinder head test. Conclusions:
I have no doubt that these figures are going to cause some conster*nation among a number of HPP's readers. The "I told you my head is better than yours" contingent should have a field day.
Before readers jump to conclu*sions based on airflow numbers alone, however, they must take into account all the other factors that compose a total engine combination. A well-set-up 400-cid engine with big-valve No.16 or No.48 D-port heads is going to run just as well as another engine with Ram Air IV heads, if the tuner doesn't have enough cam and gearing to utilize the higher-lift airflow
I'm sure our readers are quite capable of drawing their own con*clusions with respect to some of these heads. I cannot resist the temptation, however, to list a few of my own opinions (see Pete's Picks"). Whether you agree with these assess*ments or not, I would imagine that most Pontiac die-hards will find the numbers researched to be of great interest.
We'll get into the complexities and complications of porting various Pontiac heads in the near future. I promise you that the surprises will be many.
Interesting on the
Best performance head 1970 Ram Air IV
Best intake port 1969-70 Ram Air V
Best exhaust port 1 968 1/2 Ram Air II
Best D-port head No.16, No.48, No.12 (tie)
Best low-compression D-port head No.96(1971)
Best low-compression post-1972 head No. 6X
Best balanced head (exhaust to intake) 1963 421 SD
Best low-lift (under .400) head 1967 No.670
Worst exhaust-to-intake port ratio 1969-70 Ram Air V
Worst intake-to exhaust ratio 1968 1/2 Ram Air II
Biggest surprise Intake port, No.17 350 head
Biggest disappointment 1969-70 RA V, 1973-74 455 SD (tie)
Biggest "sleeper" 1975 No. 5C
Most undercammed 1963 SD, 1971 455 HO, 1973-74 455 SD (tie)
Most underexhausted 1964 GTO (No.9770716)
Most potential for porting 1973-74 455 SD, 1968 1/2 RA II (tie)
A good low lift head.[/QUOTE]
Interesting ,on the 16 castings..I new they were good,not that good.. ( traded a set of 7K3 ported castings,for 16 castings. They lapped fair, loose guides...) The compression went 2 + points up, you already know what happens here...That 17 casting,is interesting.. Picked up a set for free, seemed to have a different intake port...
I have no doubt that these figures are going to cause some conster*nation among a number of HPP's readers. The "I told you my head is better than yours" contingent should have a field day.
Before readers jump to conclu*sions based on airflow numbers alone, however, they must take into account all the other factors that compose a total engine combination. A well-set-up 400-cid engine with big-valve No.16 or No.48 D-port heads is going to run just as well as another engine with Ram Air IV heads, if the tuner doesn't have enough cam and gearing to utilize the higher-lift airflow
I'm sure our readers are quite capable of drawing their own con*clusions with respect to some of these heads. I cannot resist the temptation, however, to list a few of my own opinions (see Pete's Picks"). Whether you agree with these assess*ments or not, I would imagine that most Pontiac die-hards will find the numbers researched to be of great interest.
We'll get into the complexities and complications of porting various Pontiac heads in the near future. I promise you that the surprises will be many.
Interesting on the
Best performance head 1970 Ram Air IV
Best intake port 1969-70 Ram Air V
Best exhaust port 1 968 1/2 Ram Air II
Best D-port head No.16, No.48, No.12 (tie)
Best low-compression D-port head No.96(1971)
Best low-compression post-1972 head No. 6X
Best balanced head (exhaust to intake) 1963 421 SD
Best low-lift (under .400) head 1967 No.670
Worst exhaust-to-intake port ratio 1969-70 Ram Air V
Worst intake-to exhaust ratio 1968 1/2 Ram Air II
Biggest surprise Intake port, No.17 350 head
Biggest disappointment 1969-70 RA V, 1973-74 455 SD (tie)
Biggest "sleeper" 1975 No. 5C
Most undercammed 1963 SD, 1971 455 HO, 1973-74 455 SD (tie)
Most underexhausted 1964 GTO (No.9770716)
Most potential for porting 1973-74 455 SD, 1968 1/2 RA II (tie)
A good low lift head.[/QUOTE]
Interesting ,on the 16 castings..I new they were good,not that good.. ( traded a set of 7K3 ported castings,for 16 castings. They lapped fair, loose guides...) The compression went 2 + points up, you already know what happens here...That 17 casting,is interesting.. Picked up a set for free, seemed to have a different intake port...
famous bob
mopar misfit
Interesting ,on the 16 castings..I new they were good,not that good.. ( traded a set of 7K3 ported castings,for 16 castings. They lapped fair, loose guides...) The compression went 2 + points up, you already know what happens here...That 17 casting,is interesting.. Picked up a set for free, seemed to have a different intake port...[/QUOTE]
not disputing anyone here, but I`ve never owned a Chrysler product that was as lite as the shipping weight. my belvedere w/ a hemi and 727 weighed in at over 3900 ! was bit-- to get down to nhra race weight.
Magazine Articles and Performance Tests
1967 Pontiac GTO
Super Stock and Drag illustrated ............. December 1966
Super Stock and Drag Illustrated ............. February 1967
Super Stock and Drag Illustrated ............. November 1967
Super Stock and Funny Car ..................... June 1967
Super Stock and Funny Car ..................... March 1968
Speed and Supercar ............................... June 1967
Drag Strip ............................................. November 1966
Car Craft ............................................... January 1967
Rodder and Super Stock .......................... December 1966
Rodder and Super Stock .......................... May 1967
Motor Trend ........................................... January 1967
Motor Trend ........................................... February 1967
Car Life ................................................. October 1967
1967 Pontiac GTO
Super Stock and Drag illustrated ............. December 1966
Super Stock and Drag Illustrated ............. February 1967
Super Stock and Drag Illustrated ............. November 1967
Super Stock and Funny Car ..................... June 1967
Super Stock and Funny Car ..................... March 1968
Speed and Supercar ............................... June 1967
Drag Strip ............................................. November 1966
Car Craft ............................................... January 1967
Rodder and Super Stock .......................... December 1966
Rodder and Super Stock .......................... May 1967
Motor Trend ........................................... January 1967
Motor Trend ........................................... February 1967
Car Life ................................................. October 1967
1967 Plymouth GTX
Super Stock and Drag Illustrated ............. February 1967
Super Stock and Funny Car ..................... June 1967
Super Stockers in Action ......................... April 1967
Hi Performance Cars ............................... February 1967
Rodder and Super Stock .......................... December 1966
Rodder and Super Stock .......................... July 1967
Popular Hot Rodding ............................... March 1967
Car and Driver ....................................... November 1966
Car and Driver ....................................... April 1967
Car Life ................................................. March 1967
Motor Trend ........................................... February 1967
Bingo-Bango
According to the Motor Trend Performance Test from January 1967
'2' 1967 Pontiac GTO 400/360 HP 'Ram Air' cars were tested.
Both were equipped with 3.90 Gears with 'Safe-T-Track' Limited-Slip differential.
And, both were equipped with 'Hurst' {yes 'Hurst'} Headers.
In stock trim, and with 'closed' Hurst Headers thru the stock exhaust system.
4-Speed ........... 14.21 @ 102.97 MPH
Automatic ......... 14.09 @ 101.10 MPH
According to the Motor Trend Performance Test from January 1967
'2' 1967 Pontiac GTO 400/360 HP 'Ram Air' cars were tested.
Both were equipped with 3.90 Gears with 'Safe-T-Track' Limited-Slip differential.
And, both were equipped with 'Hurst' {yes 'Hurst'} Headers.
In stock trim, and with 'closed' Hurst Headers thru the stock exhaust system.
4-Speed ........... 14.21 @ 102.97 MPH
Automatic ......... 14.09 @ 101.10 MPH
Saint Nick
Hamilton Plymouth out of Michigan did go with a 'Performance Test' on the
GTX in 1967.
Equipped Car
* Automatic
* 3.55 Gears
* Tires .... Goodyear 7.75 x 14"
Stock Performance Tests @ Motor City Dragway
Test results ranged from {14.71 to 14.93} in 'Stock Trim'.
Best Run ......... 14.71 @ 96.8 MPH
Reported problems with Traction {obviously}, and inconsistent shifting
with the 727 Torque-Flite {Governor hang up}.
Back to the Dealership for adjustments >
#1 ........ Replace Torque-Flite Governor unit with a high-speed assembly.
#2 ........ Performance Tune-Up
#3 ........ Intake Manifold Heat-Riser Block-Off Gasket
#4 ........ Heat-Riser between Carburetor and Intake Base
> Back To The Track
Test Results ranged from 14.29 to 14.47
Best Run ...... 14.29 @ 99.10 MPH
Hamilton Plymouth out of Michigan did go with a 'Performance Test' on the
GTX in 1967.
Equipped Car
* Automatic
* 3.55 Gears
* Tires .... Goodyear 7.75 x 14"
Stock Performance Tests @ Motor City Dragway
Test results ranged from {14.71 to 14.93} in 'Stock Trim'.
Best Run ......... 14.71 @ 96.8 MPH
Reported problems with Traction {obviously}, and inconsistent shifting
with the 727 Torque-Flite {Governor hang up}.
Back to the Dealership for adjustments >
#1 ........ Replace Torque-Flite Governor unit with a high-speed assembly.
#2 ........ Performance Tune-Up
#3 ........ Intake Manifold Heat-Riser Block-Off Gasket
#4 ........ Heat-Riser between Carburetor and Intake Base
> Back To The Track
Test Results ranged from 14.29 to 14.47
Best Run ...... 14.29 @ 99.10 MPH
UGGH !!!
Motor Trend Magazine ..... February 1967
1967 Plymouth GTX 440/375 HP ~ Automatic ~ 3.23 Gears
Performance ........... 15.40 @ 94.0 MPH
Motor Trend Magazine ..... February 1967
1967 Plymouth GTX 440/375 HP ~ Automatic ~ 3.23 Gears
Performance ........... 15.40 @ 94.0 MPH
Johnny Rocco
Strictly Stock
Road Test Magazine.... June 1967
1967 Plymouth GTX 440/375 HP ~ Automatic ~ 3.23 Gears .............. 14.96 @ 96.98 MPH
1967 Pontiac GTO 400/335 HP ~ Automatic ~ 3.36 Gears ................. 15.13 @ 96.80 MPH
1967 Pontiac GTO 400/360 HP 'Ram Air' ~ Automatic ~ 3.90 Gears .... 14.30 @ 101.20 MPH
Strictly Stock
Road Test Magazine.... June 1967
1967 Plymouth GTX 440/375 HP ~ Automatic ~ 3.23 Gears .............. 14.96 @ 96.98 MPH
1967 Pontiac GTO 400/335 HP ~ Automatic ~ 3.36 Gears ................. 15.13 @ 96.80 MPH
1967 Pontiac GTO 400/360 HP 'Ram Air' ~ Automatic ~ 3.90 Gears .... 14.30 @ 101.20 MPH
-
