Pontiacs

Pontiac 421 V8 Engine
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THE FIRST MUSCLE CAR - Pontiac GTO - History 1964 - 1974
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Introduction: The Pontiac GTO is considered by many the first true muscle car. Whereas other manufacturers were concentrating on their full size lines, Pontiac saw the potential for dropping a big block engine into an intermediate frame and marketing it at a budget price. Pontiac sneaked past the GM restriction on this combination by making the GTO an option on the Tempest model, creating the hottest performance machine yet. The GTO sold in great numbers and would fuel the competition between GM, Ford, and Chrysler that would keep the muscle car industry thriving for years to come. The GTO would later evolve into the Judge, an extroverted option package of the blotted GTO, and would continue the tradition until the GTO died an embarrassing death in 1974.

1964 Pontiac Tempest GTO

Comments: The year was 1964 and the early stages of the muscle car era were dominated by full size cars. At GM, corporate policy prohibited any intermediate size car from having engines greater than 330 cid. The engineers at Pontiac had a different idea. They boldly made their 389 cid engine an option on the midsize Tempest and called the option package GTO, which copied Ferrari's GTO (Gran Turismo Omologato) model. The GTO package included the 389 V8, quick steering, dual exhaust, and premium tires, a bargain at just $300. The 389 cid engine came with 325bhp with a single 4bbl carb or 348bhp with the optional Tri-Power setup, 3 2bbl carbs. Pontiac hoped to sell 5,000 copies, they ended up selling 32,450. The car that was marketed under a Tiger motif but soon became known as the "Goat" would stand the automobile industry on end and lead to a host of imitators. But no one in the mid-sixties would get it together quite like Pontiac.

Production: Sports Coupe: 7,384 Hardtop Coupe: 18,422 Convertible: 6,644
Engines: 389 V8 325 bhp @ 4800 rpm, 428 lb-ft @ 3200 rpm. 389 V8 (3x2) 348 bhp @ 4900 rpm, 428 lb-ft @ 3200 rpm.
Performance: 389/325: 0-60 in 7.5 sec, 1/4 mile in 15.7 sec @ 92 mph. 389/348: 0-60 in 6.6 sec, 1/4 mile in 14.8 sec @ 95 mph

1965 Pontiac Tempest GTO

Comments: The success of the 1964 model prompted Pontiac to improve the GTO for 1965. Front and rear styling were changed with the GTO getting stacked headlights like Pontiac's full size models. Both versions of the 389 were improved and Pontiac released an over the counter kit that would turn the decorative hood scopes into the first functional ram air setup. These improvements obviously worked as Pontiac sold 75,342 copies, of which 20,547 had the tri-power option.

Production: Sports Coupe: 8,319 Hardtop Coupe: 55,722 Convertible: 11,311
Engines: 389 V8 335 bhp @ 5000 rpm, 431 lb-ft @ 3200 rpm. 389 V8 (3x2) 360 bhp @ 5200 rpm, 431 lb-ft @ 3600 rpm. 389 V8 Ram Air 360bhp @ 5200 rpm, 431 lb-ft @ 3600 rpm
Performance: 389/360 (3x2): 0-60 in 6.1 sec, 1/4 mile in 14.7 sec @ 99mph.

1966 Pontiac GTO

Comments: Pontiac made the GTO its own model for 1966 and was rewarded with sales of 96,946 units, the highest ever for a true muscle car. The GTO was restyled again for 1966 with gorgeous coke-bottle contours with the roof and taillights receiving the most attention. Engine choices remained the same until mid year when GM banned multi-carb setups for all cars except the Chevrolet Corvette, probably in the face increasing emissions standards.

Production: Sports Coupe: 10,363 Hardtop Coupe: 73,785 Convertible: 12,798
Engines: 389 V8 335 bhp @ 5000 rpm, 431 lb-ft @ 3200 rpm. 389 V8 360 bhp @ 5200 rpm, 424 lb-ft @ 3600rpm. 389 V8 Ram Air 360 bhp @ 5200 rpm, 424 lb-ft @ 3600 rpm
Performance: 389/360: 0-60 in 6.5 sec, 1/4 mile in 14.65 sec @ 98mph.

1967 Pontiac GTO

Comments: Undaunted by the death of their tri-power setup, Pontiac unveiled an all new 400 cid enlargement of the 389 cid engine. The rear and grill were restyled again and the new 400 cid engine was available in economy (255bhp), standard (335bhp), High Output (HO) (360bhp) and Ram Air (360bhp) versions. The tiger could still roar.

Production: Sports Coupe: 7,029 Hardtop Coupe: 65,176 Convertible: 9,517
Engines: 400 V8 255 bhp @ 4400rpm, 397 lb-ft @ 4400 bhp. 400 V8 335 bhp @ 5000 rpm, 441 lb-ft @ 3400 rpm. 400 V8 HO 360 bhp @ 5100 rpm, 438 lb-ft @ 3600 rpm. 400 V8 Ram Air 360 bhp @ 5100 rpm, 438 lb-ft @ 3600 rpm.
Performance: 400/255: NA. 400/335: NA. 400/360 HO: 0-60 in 6.6 sec, 1/4 mile in 14.66 sec @ 99mph. 400/360 Ram Air: NA.

1968 Pontiac GTO

Comments: The GTO was drastically restyled for 1968 and gained GM's new split wheelbase A-body. The GTO now sat on a 112 inch wheelbase but was still heavier than the 1967 models. The main news was the new Endura bumper, which was a rubber bumper that gave the car a bumper-less appearance. Furthermore, it was virtually indestructible, as demonstrated in a famous commercial with John DeLorean bashing a GTO's bumper with a sledgehammer, to no effect. A new option was hidden headlights, which were so common that many people thought they were standard. The engine choices remained the same, with the economy and standard 400 cid receiving more horsepower, and all engines were tuned for more torque at lower rpms.

Production: Hardtop Coupe: 77,704 Convertible: 9,980
Engines: 400 V8 265 bhp @ 4600 rpm, 397 lb-ft @ 2400bhp. 400 V8 350 bhp @ 5000 rpm, 445 lb-ft @ 3000 rpm. 400 V8 HO 360 bhp @ 5100 rpm, 445 lb-ft @ 3500 rpm. 400 V8 Ram Air 360 bhp @ 5400 rpm, 445 lb-ft @ 3800 rpm.
Performance: 400/360 HO: 1/4 mile in 14.25 seconds @ 99.0 mph. 400/360 Ram Air: 0-60 in 6.4 sec, 1/4 mile in 14.5 sec @ 98mph.

1969 Pontiac GTO

Comments: The big news for 1969 was the introduction of a new option for the GTO. Rumored to be a sleeper budget model to combat the Plymouth Road Runner, it actually was the opposite. Named after a phrase on the TV show "Laugh In", the Judge was actually a $332 option package that included a new 366bhp Ram Air III 400 cid V8, outrageous body paints, a large rear spoiler, and decals throughout. New to both versions of the GTO was a Ram IV 400 cid V8 seriously underrated at 370bhp, as well as restyled taillights, deletion of the vent windows, and the discontinuation of the HO engine.

Production: Hardtop Coupe: 58,126 Convertible: 7,328 Judge Hardtop Coupe: 6,725 Judge Convertible: 108
Engines: 400 V8 265 bhp @ 4600 rpm, 397 lb-ft @ 2400 bhp. 400 V8 350 bhp @ 5000 rpm, 445 lb-ft @ 3000 rpm. 400 V8 Ram Air III 360 bhp @ 5100 rpm, 445 lb-ft @ 3600 rpm. 400 V8 Ram Air 366 bhp @ 5100 rpm, 445 lb-ft @ 3600 rpm. 400 V8 Ram Air IV 370 bhp @ 5500 rpm, 445 lb-ft @ 3900 rpm.
Performance: 400 RA III/360: 1/4 mile in 13.89 sec. @ 101.4 mph. 400/366 Ram Air: 1/4 mile in 13.70 sec. @ 103.6 mph. 400/370 Ram Air IV: 0-60 in 6.2 sec, 1/4 mile in 14.4 sec @ 98mph.

1970 Pontiac GTO

Comments: The GTO was radically restyled for 1970 and received a new front end with four exposed headlamps wrapped in a Endura bumper, new body creases, and a redesigned rear end. The economy engine was dropped, but a new 455cid engine was added (though it was not available until the end of the 1970 season on the Judge), signaling the end of GM's ban on intermediates with engines greater than 400cid. The GTO had evolved into more of a luxo-cruiser than all-out muscle car, as was the market trend at the time.

A rare option on the 1970 GTO was the Vacuum Operated Exhaust (VOE - Option Code W-73) option. The VOE option was an attempt to simplify the old hot rod trick of opening up the exhaust system for more power. With the VOE option, the driver could pull on a knob under the dash and engine vacuum was routed to a diaphragm on each muffler. The diaphragm opened an internal baffle and gave the exhaust an express route through the muffler. The device reduced backpressure (and thus increased power), but it also significantly increased the noise level caused by the exhaust. This option was available only from early November 1969 through January 1970. That was when Pontiac aired a controversial commercial during the Super Bowl that showed off its VOE option. Top GM executives saw the commercial, and immediately cancelled the option, due to the Federal government's increasing restrictions on emissions and noise levels. Only 233 GTO's were built with the VOE option in that short time, which was priced at just $63.19.

Production: Hardtop Coupe: 32,737 Convertible: 3,615 Judge Hardtop Coupe: 3,629 Judge Convertible: 168
Engines: 400 V8 350 bhp @ 5000 rpm, 445 lb-ft @ 3000 rpm. 400 V8 Ram Air III 366 bhp @ 5100 rpm, 445 lb-ft @ 3600 rpm. 400 V8 Ram Air IV 370 bhp @ 5500 rpm, 445 lb-ft @ 3900 rpm. 455 V8 360 bhp @ 4300 rpm, 500 lb-ft @ 2700 rpm.
Performance: 400/366 Ram Air III: 0-60 in 6.0 sec, 1/4 mile in 14.7 sec @ 98mph.

1971 Pontiac GTO

Comments: In 1971, Pontiac GTO sales which had been declining since the late sixties crashed. Only 374 Judges were produced (including just 17 convertibles), despite having the 455 engine as standard, and this would be its last year. The GTO was also in its last year as its own separate model. Furthermore, GM announced that all engines would have to run on unleaded gas to meet new government regulations and compression ratios and power ratings plummeted. The front end was restyled and Pontiac tried to compensate for the drop in engine power by adjusting the axle ratio and carburetor but to no avail. Performance and sales were on the decline and nothing could hide that.

Production: Hardtop Coupe: 9,497 Convertible: 661 Judge Hardtop Coupe: 357 Judge Convertible: 17
Engines: 400 V8 300 bhp @ 4800 rpm, 400 lb-ft @ 3600 rpm. 455 V8 325 bhp @ 4400 rpm, 455 lb-ft @ 3200 rpm. 455 V8 HO 335 bhp @ 4800 rpm, 480 lb-ft @ 3600 rpm.
Performance: 400/300: 1/4 mile in 14.4 seconds @ 98 mph.

1972 Pontiac GTO

Comments: 1972 saw the GTO revert back to an option on the LeMans and Lemans Sport, costing just $353.88. The Judge was discontinued along with the convertible models (although one GTO convertible is rumored to have been built, along with three (gasp) GTO station wagons). The most noticeable change was in the engine power ratings, which dropped dramaticly. This difference reflected the industry switch from an engine's gross output (power with no accessories) to its SAE Net output (power with accessories attached). This was supposed to be more representative of the actually power delivered to the wheels -- although that didn't really ease the pain for performance seekers. The 400 V8 was now rated at 250 bhp (net) while the 455 was available in either 250 or 300 bhp versions.

Production: Hardtop Coupe: 5,807
Engines: 400 V8 250 bhp @ 4400 rpm, 325 lb-ft @ 3200 rpm. 455 V8 250 bhp @ 3700 rpm, 325 lb-ft @ 2400 rpm. 455 V8 HO 300 bhp @ 4000 rpm, 415 lb-ft @ 3200rpm.
Performance: 455/300: 1/4 mile in 14.6 seconds @ 95.2 mph.

1973 Pontiac GTO

Comments: 1973 saw the end of the once great GTO. New government regulations eliminated the Endura bumper and added a heavy, odd-looking steel one. The hood and tail took on displeasing triangular shapes and this would be the last year the GTO would be based on the LeMans. The 400 V8 was rated at just 230 bhp while the 455 was rated at 250 bhp and was only available with an automatic transmission.

Production: 4,806
Engines: 400 V8 230 bhp @ 4400 rpm, 325 lb-ft @ 3200 rpm. 455 V8 250 bhp @ 3700 rpm, 370 lb-ft @ 2800 rpm.
Performance:

1974 Pontiac GTO

Comments: For 1974, its last year, the once proud GTO was reduced to an option on the compact Ventura, either as a hatchback or a coupe. Only one engine was offered, a 350 V8 rated at a mere 200 bhp. This marked the first (and only) time the GTO came with any engine smaller than 389 cid, but at least it came standard with the classic "shaker hood" air scoop. Although it died a painful death, the GTO will always be remembered as the Great One that started it all.

Production: 7,058 (2D Coupe: 5,335 2D Hatchback: 1,723)
Engines: 350 V8 200 bhp.
Performance: 0-60 in 7.7 seconds, 1/4 mile in 15.72 seconds @ 88 mph.

http://ronspontiacpage.com/reference-pages/stockflowcharts.htm

http://www.wallaceracing.com/ultimatehead.htm

http://www.wallaceracing.com/ultimateflow.htm

http://www.jbp-pontiac.com/Articles/HPPP-130100-RO.pdf

http://www.cartechbooks.com/techtips/cylinder-heads-performance-guide-for-pontiac-v-8-engines/

http://www.krepower.com/Pontiac Aluminum High Port Cylinder Heads.htm

http://www.krepower.com/Pontiac Intakes.htm

http://www.wenzlerengineering.com/gutsram.htm

http://users.erols.com/srweiss/tablehdc.htm#Pontiac

http://www.frankspontiacparts.com/engineparts/pontiacengines.htm

http://www.frankspontiacparts.com/engineparts/transmissionparts.htm

http://www.frankspontiacparts.com/engineparts/suspensionparts.htm

http://www.wallaceracing.com/axledata2.htm

http://www.teufert.net/identify/identify.htm

http://www.pontiacpower.net/castnum01.html

http://www.wallaceracing.com/engine.htm

http://wallaceracing.com/head1.htm

http://www.antiquecarparts.net/tech04.htm

http://ronspontiacpage.com/reference-pages/stockheadspecs.htm

http://www.pontiacpower.net/numbers/head-codes/

http://www.classicpontiac.org/FAQ.asp?myPage=V8HeadInfo

http://www.pontiacracing.net/head.htm

http://www.hotrod.com/how-to/engine/0312pon-4x-6x-racing-heads/

http://www.antiquecarparts.net/tech03.htm

http://www.antiquecarparts.net/tech01.htm

http://www.antiquecarparts.net/tech02.htm


for the guys that want to convert flow rates between rated vacuum or listed test depressions,
EXAMPLE
if it was meassured a 12" and you want to convert it to 28" which is more or less the standard

http://users.erols.com/srweiss/calcdchg.htm

http://www.teufert.net/pontiac/intake.htm

http://www.2gta.com/72_455ho.html

http://ronspontiacpage.com/reference-pages/intakemanifoldpartnumbers.htm
Pontiac Intake Manifold Part Numbers
Year Part Number Engine Displacement Description
1962
541690 389 348hp Auto
1964 9770274 389 GTO 4bbl
1964 9775088 389/421 GTO Tripower
1965 9778816 389 GTO 4bbl
1965 9778818 389/421 GTO Tripower
1966 9782808 421 Manual
1966 9782896 389 GTO 4bbl
1966 9782898 389/421 GTO 389 Auto and Manual, 412 Auto, Tripower
1966 9784440 421 Auto with A.I.R.
1967 9784438 400 GTO 2bbl, 225hp
1967 9786286 400 GTO 4bbl
1968 9790140 350/400 Firebird (350HO, 400, 400HO, 400 Ram Air I), GTO
1968 9790418 350/400 Firebird, Fullsize (2bbl 350), GTO (2bbl 400)
1968 9790418 350 Firebird 2bbl
1968 9794231 250 Firebird 1bbl
1968 9794232 250 Firebird 4bbl Sprint
1968 9794233 400 2bbl early and late (not Firebird)
1968 9794234 400 Firebird RA II, 4bbl late (including 350HO)
1968 9794234 400 RA IV Firebird RA IV, 2-piece Aluminum
1969 9794231 250 Firebird 1bbl
1969 9794232 250 Firebird Sprint 4bbl
1969 9794233 350/400 Firebird (2bbl 350), GTO (2bbl 400)
1969 9794234 350/400 Firebird All (4bbl 350HO, 4bbl 400, 4bbl 400HO, RA III), GTO 4bbl
1969 9796395 400 RA IV GTO RA IV w/ Exhaust Crossover
1969 9796614 400 RA IV Firebird (RA IV, 2-piece Aluminum), GTO (RA IV, 2-piece Aluminum)
1970 9796395 400 RA IV GTO RA IV w/ Exhaust Crossover
1970 9799067 350/400 Firebird 2bbl
1970 9799068 400 Firebird (4bbl, RA III), GTO (4bbl)
1970 9799084 400 RA IV Firebird (RA IV, 2-piece Aluminum), GTO (RA IV, 2-piece Aluminum)
1971 481732 350/400 Firebird 2bbl
1971 481733 400/455 Firebird 4bbl
1971 483674 455HO 2-piece Aluminum
1972 485640 455HO 2-piece Aluminum
1972 485911 350/400 Firebird 2bbl
1972 485912 350/400/455 Firebird 4bbl
1972 488945 455HO 2-piece Aluminum
1973 491244 400/455 Firebird 4bbl
1973 492292 350/400 Firebird 2bbl
1973 492744 400/455 Firebird 4bbl
1973 494282 400/455 Firebird 4bbl
1973 494405-19 455SD Firebird 4bbl (LS2 or LS2X cast into front of the manifold)
1974 495104 350/400 Firebird 2bbl
1974 495106 350/400 Firebird 4bbl
1974 495107 455SD Firebird 4bbl Super Duty
1975 496140 400/455 Firebird 4bbl
1975 496142 350 Firebird 2bbl
1976 525355 400/455 Firebird 4bbl
1976 5255353 350 Firebird 2bbl
1977 525355 350/400 Firebird 4bbl
1977 526213 301 Firebird 2bbl
1978 10003395 400 Firebird 4bbl
1979 10000516 301 Firebird 2bbl
1979 10000518 301 Firebird 4bbl
1979 10003395 400 Firebird 4bbl

https://www.npdlink.com/store/catalog/Intake_Manifold-10248-1.html

http://www.hotrod.com/how-to/engine/hppp-0904-factory-cast-aluminum-intake-manifold-comparison/
actory Cast-Aluminum
Intake Manifold Casting Numbers
Number
Application
9796614 '69 A-body R/A-IV
9799084 '69 F-body R/A-IV
9799084 '70 R/A-IV
483674 '71 455 H.O.
485640 '72 455 H.O. (early)
488945 '72 455 H.O. (midyear)
Pontiac Intake Manifolds
YEAR PART NUMBER SIZE DESCRIPTION
1958-60 536193 ??? TRIPOWER MANIFOLD
1958-60 536516 ??? 4 BARREL
1962 541690 389 348 HP WITH AUTOMATIC (425A TROPHY ENGINE)
1962 542991 421 SUPER DUTY 2 X 4
1963 9770319 421 SUPER DUTY 2 X 4
1964 9770274 389 GTO 4BBL
1964 9775088 389/421 TRIPOWER
1964 9775088 389 GTO TRIPOWER
1965 9778816 389 GTO 4BBL
1965 9778818 389/421 GTO TRIPOWER
1965 9778818 389 GTO TRIPOWER
1966 9782808 421 MANUAL
1966 9782896 389 GTO 4BBL
1966 9782898 389/421 389 AUTO & MANUAL AND 421 AUTO tripower
1966 9782898 389 GTO TRIPOWER
1966 9784440 421 AUTO WITH A.I.R.
1967 9784438 400 225 HP 2BBL GTO
1967 9786286 400/428 Quadrajet type intake, used on all 400 Lemans/GTO/Firebird & fullsize with 428
1967 9782896 326/400 Carter type intake, used on 326 (Tempest & Firebird) and 400 in fullsize and GP
1968 9790140 350/400 350 HO,400,400HO,400RAM AIR I FB & GTO
1968 9790140 400 FB 4 BARRELL (STD, HO, & RAM AIR I)
1968 9790418 350 2 BBL FIREBIRD & BIG CAR
1968 9790418 400 2BBL GTO EARLY & LATE
1968 9790418 350 FB 2 BARELL
1968 9794231 250 1 BBL FIREBIRD
1968 9794231 250 FB 1 BARRELL
1968 9794232 250 4 BBL SPRINT FIREBIRD
1968 9794232 250 FB SPRINT 4 BARRELL
1968 9794233 400 2BBL EARLY & LATE (NOT FB)
1968 9794234 400 FB RAM AIR II
1968 9794234 400 4BBL LATE (NOT FB OR GP)
1968 9794234 400 FB ALUMINUM 2PC RAM AIR IV
1969 9794231 250 1 BBL FB
1969 9794231 250 FB 1 BARRELL
1969 9794232 250 4BBL SPRINT FB
1969 9794232 250 FB SPRINT 4 BARRELL
1969 9794233 400 2BBL GTO
1969 9794233 350 2BBL FB
1969 9794233 350 FB 2 BARELL
1969 9794234 400 4BBL GTO
1969 9794234 350/400 350 4BBL HO,400 4BBL, 400 HO 4BBL,RAM AIR III (ALL FB)
1969 9794234 350/400 FB 4 BARRELL (STD, HO, & RAM AIR III)
1969 9796395 400 RAM AIR IV GTO EXHAUST CROSSOVER
1969 9796614 400 RAM AIR IV GTO ALUMINUM 2 PC
1969 9796614 400 RAM AIR IV ALUMINUM 2 PC MANIFOLD FB
1969 9796614 400 RA IV FB ALUMINUM 2PC RAM AIR IV
1970 9796395 400 RAM AIR IV EXHAUST CROSSOVER GTO
1970 9799067 350 2BBL FB
1970 9799067 400 2BBL FB
1970 9799068 400 STANDARD 4BBL GTO
1970 9799068 400 400 4BBL AND RAM AIR III 4BBL FB
1970 9799068 400 FB 4 BARRELL (STD & RAM AIR III)
1970 9799084 400 RAM AIR IV ALUMINUM INTAKE GTO
1970 9799084 400 RAM AIR IV ALUMINUM 2 PC MANIFOLD FB
1970 9799084 400 RA IV FB ALUMINUM 2PC RAM AIR IV
1971 481732 350/400 FB 2 BARELL
1971 481733 400/455 STANDARD 4BBL
1971 481733 400/455 FB 4 BARRELL
1971 483674 455 HO ALUMINUM INTAKE
1971 483674 455 HO ALUMINUM 2 PC MANIFOLD
1971 483674 455 HO ALUMINUM 2 PC
1972 485640 455 HO ALUMINUM 2 PC MANIFOLD
1972 485911 350/400 FB 2 BARELL
1972 485912 400/455 STANDARD 4BBL
1972 485912 350/400 FB 4 BARRELL
1972 488945 455 HO ALUMINUM 2 PC
1973 491244 400/455 FB 4 BARRELL
1973 492292 350/400 FB 2 BARELL
1973 492744 400/455 FB 4 BARRELL
1973 494282 400/455 FB 4 BARRELL
1973 494405-19 455 SD FB 4 BARRELL(HAS LS2 OR LS2X CAST IN FRONT OF MANIFOLD
1974 495104 350/400 FB 2 BARELL
1974 495106 350/400 FB 4 BARRELL
1974 495107 455 SD FB 4 BARRELL SUPERDUTY
1975 496140 400/455 FB 4 BARRELL
1975 496142 350 FB 2 BARELL
1976 525355 400/455 FB 4 BARRELL
1976 5255353 350 FB 2 BARELL
1977 525355 350/400 FB 4 BARRELL
1977 526213 301 FB 2 BARELL
1978 10003395 400 FB 4 BARRELL
1979 10000516 301 FB 2 BARRELL
1979 10000518 301 FB 4 BARRELL
1979 10003395 400 FB 4 BARRELL
1978 9799067 350/400 FB 2 BARELL
??? 9786285 ??? 4 BARREL
 
Last edited:
You have to be careful about online published Factory Pontiac Heads airflow
charts Grumpy.
They are all from High Performance Pontiac 1991.
Pete Mcarthy tested with another on a homemade flow bench.
And tested at 12" inches instead of Smokey Yunick Baseline 28".
Can convert of course.
I pay attention to the E/I FLOW RATIOS.
Remains the same no matter if flow tested at 12, 28, 50 , 100 & 200 ".
 
On lunch.
Gives me something to read.
Thanks.
KRE or Kaufman be nice.
Have to wait.
 
I like High Velocity heads Grumpy.
Airflow will be there.
Scavange 5th cycle used.
330 cfm get the Job done Yes.
 
A Nostalgia Pontiac SuperStock Racer I knew in the past swears by Wenzler.
He also raced with 5.13-5.38 gears.
Turned 9,000 rpm through the traps.

After High Velocity Heads.
How Street Races are Won.
You know also Grumpy.
None ever publish head velocity numbers.
Must study flow charts and low to mid airflows. Take a mean average.
What the engine actually sees and takes in.
 
I read the JBP Article on 1972-79 Pontiac heads with an early 1967-71 Q-jet iron intake used.
I made Copper blockoff plates about .025" thick for my 1970 Ram Air 4 heads Grumpy.
Seperate cast iron crossover used with the Factory aluminium intake.
Works too.
 
I converted-calculated using Weisse site Grumpy.
Almost 310 cfm 614's RAIV.
Not bad.
Will work again for now for me.
 
Change the Flow depression from 28 to 50 & 100 & 200 Grumpy.
What a running engine actually sees.
Peak Flow numbers are a Joke.
 
Found something else interesting Grumpy.....
KRE Bad news too.
Post link on my own thread too.
If I had the $$$$ To buy aftermarket Aluminium ...It would be Fupler E Heads.
Never realized he is like Me....
 
great catch there!
and useful info!
E heads probably best.
I think Fupler does know more about them than everyone else.
He likes Engine Rocket science like us.
His small site and postings says it.
 
Fupler also Ran RA4 iron heads in the past.
Knows a lot.
 
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