The Ram Air Inlet option (Code 611) eliminated the die-cast "400"
emblems, replaced with "Ram Air" stickers. This required the
Firebird 400 hoods to NOT have holes punched for the emblems.
The standard Firebird 400, and the Firebird Ram Air (later called 400 H.O.) had closed hood scoops, and a pair of die-cast "400" emblems.
The engine was equipped with a single snorkel enclosed air cleaner, with a chrome lid. The Firebird 400 model was very similar to the GTO
option, where the Firebird 400 option contained special emblems, dual exhaust, Turbo 400 transmission (on automatic equipped cars),
chrome rocker arm covers, chrome air cleaner lid, and beefier suspension.
|1969 Pontiac Firebird Ram Air Setups
Pontiac's Ram Air system debuted in 1965 as an over-the-counter package on the GTO. As the term "Ram Air" became part of the
vocabulary for every high performance enthusiast, Pontiac brought the Ram Air setup out of the Parts Department and into the
production line. The 1965-1967 GTO Ram Air setup (not including engine changes) consisted of a lower "bathtub" steel pan, a foam
seal, and an open hood scoop. When the hood closed, the lower pan sealed against the underside of the hood, and only cool, fresh
air was ingested into the carb(s). The Ram Air pan was only available for the tri-power equipped GTO's from 1965-1966. When
Pontiac discontinued their multiple carburetor setup for 1967, the new 1967 Ram Air pan would sit over a 4-barrel Quadrajet
carburetor, and the 1967 setup housed a large 14" x 3" air filter that sat in the bottom tub.
Because the 1965-1967 GTO's had a centrally located hood scoop, there was no need for any type of upper pan on the underside of
the hood to channel incoming air to the carb. It was as simple as getting the lower tub to seal against the underside of the hood.
1) Standard 330 hp engine, closed hood scoops, single-snorkel enclosed air cleaner with a chrome lid.
2) Optional 335 hp Ram Air engine (later known as the 400 H.O.). This option did NOT include the Ram Air setup or open
hood scoops, even though it was called the "Ram Air" engine. During the course of the 1969 model year, Pontiac changed
the name from "Ram Air" to "400 H.O.". Throughout the entire model year, a buyer had to order Option 611 (Ram Air Inlet)
to get the Ram Air setup and open hood scoops. This engine would also be called the Ram Air III.
3) Optional 345 hp Ram Air IV engine. This option included the Ram Air setup. The Firebird RAIV and Firebird Ram Air
setups were different, as we shall see later.
1) Standard 335 hp Ram Air engine. The Ram Air setup was included, but differed from the Firebird 400 Ram Air system.
This engine would also be called the Ram Air III later in the model year.
2) Optional 345 hp Ram Air IV engine. The Ram Air setup was included, but differed from the Firebird 400 Ram Air system.
|Differences in the 1969 GTO and 1969 Firebird 400 hoods
The factory Pontiac photograph above is the best example I've seen comparing the 1969 GTO to the 1969 Firebird 400. As you can
see, the Firebird's hood scoops are placed much farther apart than the GTO's. Also, the trademark "ironing board" hood seen on so
many Pontiacs is much wider on the Firebird, and the hood scoop openings themselves are wider on the Bird. Also interesting to
note is that the Firebird sat 1" lower than the GTO, yet was nearly the same width.
The hood scoops do NOT interchange between these two models. They are of a different shape and contour. And the steel Ram Air
"flapper" plate that opens/closes the hood scoops (driver controlled) also does not interchange, because the Firebird scoops are
farther apart than the GTO's. In fact, there are hardly any parts that interchange between these two setups.
The base Firebird 400 (330 hp) used an enclosed, single snorkel air cleaner, and a chrome lid. All Firebird 400's came with the
dual-scooped hood, closed hood scoops, and a die-cast "400" emblem on each hood scoop nacelle. Each emblem had two studs, and
were attached with speed nuts from the backside. All the Firebird 400 hoods had holes punched for the "400" emblems, including
the Firebird 400 Ram Air (later named Firebird 400 H.O.) if the customer did not order Option 611 (Ram Air Inlet).
All Firebird OHC-6, Firebird 350, and Firebird 350 H.O. cars used a flat hood, without any hood scoops.
|1969 Firebird 400 - Option 611 (Ram Air Inlet)
As discussed above, if you ordered a Ram Air Firebird, you received the Ram Air engine (a.k.a. 400 H.O.), but you didn't get the
Ram Air setup. In order to get the Ram Air System, you had to order Option 611 (Ram Air Inlet) priced at $84.26. The Ram Air Inlet
was not available on the standard Firebird 400, only the Ram Air (400 H.O.). The Ram Air setup was included in the price of the
Ram Air IV package and on the Trans Am. NOTE : I have an example where Option 611 was on a Trans Am invoice, but I believe
this was an anomaly, and not standard practice.
On invoices, Pontiac used the term "F/B 400 R/A" to signify the Ram Air engine. But the customer still had to order Option 611
(Ram Air Inlet) to get Ram Air. Understandably confusing, I'm sure more than one customer back in 1969 assumed that ordering a
Ram Air engine meant you would get Ram Air. And I'm sure more than one customer was a little upset when they took delivery of
their new Firebird and discovered closed hood scoops, and an enclosed single snorkel air cleaner under the hood. And some
customers were probably very suspicious of a Pontiac salesman insisting they had to buy an $84.26 option (which would be a few
hundred dollars in today's money) to order a Ram Air Inlet on top of an expensive Ram Air engine option. Perhaps because of the
confusion, later in the year Pontiac changed their invoices to show "F/B 400 HO", but still the customer had to order Option 611
(Ram Air Inlet) to get Ram Air.
Now for that $84.26 charged for the Ram Air Inlet, the customer received quite a few unique parts. First off, a different hood was
used. The Ram Air Inlet option (and Ram Air IV option) did not use die-cast "400" emblems, but rather a set of Ram Air (or Ram Air
IV) stickers on the hood scoops, the same stickers that graced the hoods of Ram Air GTO's and Judges. That meant the holes would
not be punched for the "400" emblems. Secondly, in order for the upper Ram Air pan foam to seal, a piece of underhood bracing
needed to be cut away. This was apparently done in the assembly plant's shop area, as original Ram Air hood show a rough cut where
the bracing was removed, probably done with a reciprocating saw.
Pontiac decided to use a different approach to the 1969 Firebird Ram Air setup than on the 1969 GTO. The Firebird Ram Air would
use the same type of setup used on the L-88 Corvette, another car with limited hood clearance. Pontiac housed the air filter in the
upper pan, held in place by a round plate with 4 screws. And to prevent debris from entering the carb while the hood was up, Pontiac
developed a stiff screen basket that sat over the carb throat (see photo). The paper filter mounted up in the hood was rather small,
measuring 9" x 2". By comparison, the GTO Ram Air setup, and in fact the 1967-1968 Firebird Ram Air setup, used a much larger
14" x 3" filter. It's no wonder that over the years, hot rodders discarded the cumbersome and restrictive 1969 Firebird Ram Air setup
in favor of an open element air cleaner. Original Firebird Ram Air pans are now reproduced, but originals are very scarce indeed.
The Ram Air hoods had a
section of bracing cut away for
the upper pan foam to seal
When viewed from above, it's easy to
see why this section of bracing on
the 400 hood had to be cut away
(arrow) to allow the foam to make a
The Ram Air system on the 1969 Firebird and Trans Am had a nearly flat
pan for a baseplate, as opposed to the tub style used for the 1967-1968
Firebirds. A screen basket, looking like an upside-down kitchen strainer,
sat over the carb. This was an elaborate, one-year only setup on the 1969
Firebird Ram Air cars. Pontiac changed the entire system for their
all-new 1970 Firebirds. Also note the black vacuum hose running from
the lower pan to the upper pan, and a second silver line. The silver line is
the pull cable for the hood scoops. Only 1969 Firebird 400's with Option
611 (Ram Air Inlet) had this cable, Trans Am's did not.
The upper pan was enormous, necessary to cover the girth of the
widely spaced Firebird hood scoops. Within the upper pan sat a
vacuum controlled diaphragm (driver's side) which opened upon
startup, allowing heat from the drivers side exhaust manifold to
enter the system, allowing quicker warm ups. In the middle of the
upper pan sits a 9" x 2" air filter, far too small to feed a 400 cube
engine. The filter was held in place with 4 small screws. The wire
strainer basket over the carb prevented the possibility of a screw
(from the air filter retaining plate) from falling down the carb
throat while changing the air filter.
The standard Ram Air pan looked strange, as it was not
symmetrical. The pan was essentially flat, with some
depressions stamped for the breather (lower left) and the
vacuum control for the vacuum diaphragm (two small
holes, upper left). It was held down to the Q-Jet carb via
special bolts in the 10 o'clock and 5 o'clock positions.
These are the totals for 1969 Firebirds ordered
with the 400 H.O. option. This would include
invoices listing "F/B 400 R/A" or "400 H.O.",
but does NOT breakout which cars were
ordered with Option 611 Ram Air Inlet.
The driver controlled Ram Air
cable was mounted under the
dashboard. Trans Am's did NOT
have driver controlled scoops, only
the Firebird 400 models, with
Option 611 Ram Air Inlet did.
The parts diagram for the 1969 Firebird Ram Air III system showing the dozens of parts involved in the Ram Air package. Note the subtle
differences in the 1969 Trans Am upper pan foam, and other minor variations over the Firebird 400 setup. Many of these subtleties are lost with
the current reproductions of the various parts today, which make original pieces even more valuable. Also of note is that Pontiac listed the 400
H.O. and Ram Air III on this diagram. An invoice may show "F/B 400 R/A" early in the year, and "F/B 400 HO" later in the year. In either
case, the buyer had to order Option 611 (Ram Air Inlet) to get Ram Air.
|1969 Firebird 400 - Ram Air IV
In 1969, the Ram Air IV engine was available on the Firebird 400 and Trans Am, as
well as GTO and Judge models. The Ram Air IV shared very few parts with the Ram
Air III engine, and the Ram Air IV is regarded as one of the most powerful engines of
the Musclecar Era.
1969 Ram Air IV Firebirds are extremely rare, and few survive today. The Ram Air
IV option was very pricey, coming in at a whopping $905.75. But for that price, you
received the Firebird 400 option ($292.79), the Ram Air IV engine, and the Ram Air
setup. Still, a $905.75 option was expensive for a car that typically stickered at
around $3,100 to $3,400.
The Ram Air IV was not for the faint of heart. A radical camshaft, round port
cylinder heads, aluminum intake, high lift 1.65 rocker arms, and various specialized
parts made up the Ram Air IV package. Because of the aggressive camshaft, 3.90
rear end gears were mandatory, 4.33 gears optional. Air conditioning was NOT
available with the Ram Air IV engine in the Firebird, Trans Am, GTO, or Judge.
The Ram Air setup on the Ram Air IV equipped Firebirds differed from the Ram Air III setup. Since air conditioning was not
available on the Ram Air IV engine, the lower pan could now be symmetrical. Also, dual vacuum diaphragms were placed in the
upper pan to receive heat from the exhaust manifold (driver's side) and the intake manifold (passenger side). Other than the change to
a symmetrical lower pan, with a matching foam seal in the shape of the new pan, and the necessary parts for the passenger side heat
riser, the other components of the Ram Air IV setup were the same as the Ram Air III.
Pontiac still used the small 9" x 2" air filter mounted in the upper pan, the same carb screen, etc. The same procedure was used for
hood preparation on the Ram Air IV as on the Ram Air III. A section of inner hood bracing was cut out (see photo above), holes
were not punched for the "400" emblems, and a pair of "Ram Air IV" stickers would grace the hood scoops.
The 1969 Firebird Ram Air IV lower pan appeared far more balanced,
from an aesthetic standpoint, than the Ram Air III version. Note the
dimples at the front and rear of the carb opening area in the 12 o'clock
and 6 o'clock positions. Pontiac originally intended this pan to be used on
the Ram Air IV and the Ram Air V Firebirds. However, Pontiac killed the
Ram Air V program before a single Firebird or GTO had been produced.
The Ram Air V would have used a Holley 780 cfm carb instead of a
Quadrajet, and the dimples in this RAV pan are for clearance of the
Holley float bowl adjustment screws.
This 1969 Firebird Ram Air IV is an extremely rare sight. Only
102 examples were ever built, and this one is a convertible 4-speed,
of which only 12 were built. As on the RAIII Ram Air setup, notice
the vacuum hose running from the baseplate to the upper pan, and
the silver pull cable for the driver controlled hood scoops. This
particular example is missing the wire mesh carb screen, which
would lay freely (no hold downs) on the carb air horn.
This 1969 Trans Am Ram Air IV is a rare sight indeed. Only 55 Trans Am's were equipped with the Ram Air IV engine in 1969.
This is the Pontiac parts diagram for the 1969 Firebird 400 RAIV lower pan setup. On the driver's side, Pontiac used a shield over the exhaust
manifold, along with a corrugated tube, to route hot air into the upper pan. On the passenger side, Pontiac used a hard plastic elbow to grab
heat off the intake manifold heat crossover, which on the Ram Air IV, was a separate piece from the intake manifold. Pontiac used two vacuum
diaphragms mounted in the upper pan that metered the heat coming up from the heat riser sources. When the car was warmed up, a
thermostatically controlled switch would divert vacuum away from the diaphragms, and the valves would close, thereby allowing only cool air
from the scoops to be ingested to the carb. A somewhat complex setup, but it worked. The downside was that there were dozens and dozens of
parts, and over the years, many of those parts were discarded by garage mechanics because of the complexity of the system.
As complex as the bottom part of the Ram Air setup was, it paled in comparison to the upper pan. This factory diagram is for the 1969 Firebird
Ram Air and Ram Air IV cars only, not the Trans Am. The detail drawings around the center drawing show the various parts of the hood scoop
operation and cable mechanism. There was actually another diagram showing how the cable was routed into through the firewall, and then the
pull cable bracket that was mounted under the dash. The more you look at these diagrams, that $84.26 charge for Code 611 (Ram Air Inlet), or
the entire Ram Air IV engine, began to look like a bargain.
The 1969 Trans Am was the pinnacle of the 1967-1969 Firebird development. With functional front and rear spoilers, special hood
with scoops mounted at the leading edge of the hood to get the most air, side air extractors to remove pressure and underhood heat,
a thicker front sway car, and a special paint scheme, the Trans Am was a very serious machine.
The 1969 Trans Am used an entirely new hood, with larger hood scoops positioned at the leading edge of the hood. This position was vastly
superior to the 1967-1969 dual scoops found on the Firebird 400's or the 1968-1970 GTO's. The dual hood scoops on those cars were
positioned about halfway back on the hood, and were out of the air stream, where the Trans Am's were positioned at the leading edge, directly
in the air stream. The 1969 Trans Am hood was made of steel (the prototype 1969 Trans Am hood was fiberglass, as the steel hood had not been
stamped up for production yet). Since all Trans Am's were equipped with either the Ram Air III or Ram Air IV, all the of the Trans Am hoods
had the inner structure bracing cut to seal the Ram Air foam (see photo earlier in this article).
The steel Trans Am hood had a pair of plastic
tubes that funneled the cold air from the leading
edge of the hood to the upper Ram Air pan.
Because these tubes were wider than the regular
Firebird 400 scoops, a different piece of foam was
used for the upper pan. The 1969 Trans Am hood
design, with the scoops at the leading edge of the
hood, would also be used on the 1971-1972 GTO,
1970 Olds 442 W-30, and the 1970-1975 Firebird
|In this factory Pontiac Parts Illustration diagram, the detail of the upper pans has been
enlarged to show the differences between the Firebird 400 and Trans Am Ram Air setups.
At the top of this diagram, you can see the shape of the foam is quite different between
the Firebird and Trans Am. Also of note is that the Ram Air III and Ram Air IV upper
pans had two vacuum diaphragms, but on the Ram Air III model (and this goes for the
GTO as well), the passenger side vacuum diaphragm was redundant. On RAIII models,
there wasn't a passenger side heat riser tube, so Pontiac installed a block off plate
between the diaphragm and the pan to prevent underhood air from entering the upper
pan. The diagram above shows the Firebird Ram Air pan without a passenger side hole
at all, but I believe this illustration was done this way to prevent the Parts Departments
(and customers) from ordering a passenger side diaphragm that served no purpose on a
Ram Air III car (thanks to Dave Armstrong for this information).
When placed side-by-side, it's very easy to tell the RAIII setup (left) verses the Ram Air IV setup (right), simply by the shape of the lower pan.
Also note that there is only one vacuum line from the baseplate to the upper pan, as there is no hood scoop cable to operate hood scoop flaps on
a 1969 Trans Am. On the Ram Air IV setup (right), there's an aluminum 2-piece intake manifold lurking underneath that baseplate. As a side
note, the silver tube mounted in front of the radiator is the power steering cooling line, a feature also used on the Grand Prix. All 1969 Trans
Am's should have this cooling line, as power steering was required on the Trans Am.
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With the introduction of the new 1967 Firebird 400, Pontiac designed a beautiful hood
with widely spaced individual hood scoop nacelles. The new Firebird Ram Air setup
consisted of a set of ; 1) open hood scoops, 2) a steel upper pan attached to the
underhood bracing, 3) a thick foam gasket between the pan and the hood, 4) a lower tub,
and 5) a circular foam seal attached to the lower tub. This allowed the widely spaced
Firebird twin hood scoops to pull in cool air into a common plenum, and in the center of
the plenum was a large circular hole. When the hood closed, the lower tub, with the large
foam seal, would seal against the upper pan. The lower tub sat directly on the carburetor
air horn, and was held down the same way as an air cleaner was, with a wingnut. In the
center of the lower tub sat a 14" x 3" air filter, allowing plenty of air for the Quadrajet
4-barrel carb. While very effective, there were a few disadvantages. The hood scoops
were always open, so in cold weather, driving (and starting) a Ram Air equipped car could
be difficult. Icing of the carb was not uncommon in cold climates, and of course rain and
snow would enter the hood scoops and accumulate in the lower tub, saturating the paper
air filter. A stop gap solution was to drill a series of holes around the bottom of the tub to
allow any rainwater to drain out. Unfortunately, this water would drip right on to select
areas of the engine, namely the hot intake manifold.
These minor drawbacks didn't matter to high-performance enthusiasts, who seldom drove
their cars in foul weather. But GM and Pontiac were in the business of selling dependable,
reliable cars. The handful of Ram Air setups and cars they sold from 1965-1968 needed a
better, more foolproof way to deal with all sorts of weather, and provide faster warm ups.
So in 1969, both the GTO and Firebird systems would be totally revamped. The 1969
setups had two main improvements over the 1968 Ram Air setup ; 1) the ability to allow
the driver to open and close the hood scoops from inside the car, and 2) a clever if not
complex series of vacuum diaphragms and flaps to get hot air to the carburetor during
cold weather starts, allowing faster warm-ups.
While the 1969 GTO Ram Air setup would be used on the 1970 GTO, the 1969 Firebird
system was a one-year only design. Overly complex, not as effective as the GTO setup,
the 1969 Trans Am and Firebird 400 Ram Air setups have become somewhat of a
mystery in Pontiac circles. It is the mysterious and complex 1969 Firebird Ram Air setups
that we will focus on in this article.
1966 GTO Ram Air
1967 GTO Ram Air
1965-1967 GTO hood scoop
- By Mike Noun
1967-1969 Firebird 400 hood scoops
1967-1968 Firebird Ram Air setup. An upper
pan gathered air from the widely spaced
The factory line drawing for the 1969 upper Ram Air pan shows how the upper pan was attached to the inner hood bracing using bolts and star
washers. The air filter itself used a lip on the inner portion of the filter. On the bottom of the filter, that lip located the filter in the center of the
retaining plate. On top of the filter was a separate foam ring, which had a sticky backing, that was attached to the top of the air filter. The
purpose of the foam on top was because the air filter would be in direct contact with the underside of the hood, and the 1969 Firebird hood,
with either the 400 hood or the Trans Am hood, had a crest down the middle, leaving a V-shaped channel that would prohibit the filter from
lying flat (air filter photos courtesy of David Armstrong).
To begin with, we must understand the terminology Pontiac used on the 1969 Firebird engines, which differed from the GTO.
The Trans Am
The Firebird 400
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|Bottom of filter,
showing the lip for
the retaining plate
|Top of filter, which would
reside against the
underside of the hood