[1969 Ram Air]

Yes, SD Formulas got the shaker hood.

[necdb3]

All formula's got the dual snorkel hood unless SD option. 350,400,455. Ram Air was a separate option.

[Held for Ransom]

Originally Posted by whiskeyd

From everything I have read thou the ram air hood is standard on the 400 and 455 455 SD got the shaker

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The Formula hood was standard on Formulas, Ram Air (opened up snorkels w/ducting to a different air cleaner assy., code WU3) was available on the 400 and 455 at an additional cost. SD455 Formulas received Ram Air in the form of the Trans Am shaker setup.

[Brewster]

Correct HFR, however the shaker was sealed (all SD-455's)thus technically it wasnt Ram Air due to noise restrictions set by feds

[bird72]

73 was weird...... Highest HiPo motor, SD was non RA. Lesser 455 in TA was no open shaker also. But get the standard 455 in a Formula, viola, RA available option. Even another step down to 400 could get RA.

[dadsformula]

This is a rare car no question, and one of 227 L75/4 speed formulas in any year
In 73 Ram Air Hood was an option, and the only difference from the standard formula
Hood is the cutouts and Screens. It was not standard on any Formula in 73.

I think the numbers in 73 are 730 total Formula 455's with 503 being Auto's and 227
Manuals. I think the total of Ram Air Formula's was around 600, and this would be
400's and 455's. To my knowledge no breakdown on this number.

You have the same PHS disappointment I had. My Car had on open hood when I got
it, but the PHS confirmed no Ram AIR. In my case finding the Original Single inlet
Air Cleaner and a non cut hood was quite the adventure. The Air Cleaner I found
on Ebay advertised as a 77 firebird (was a date coded 73) and is the only one Ive
seen for sale in a while. The Hood, I bought a rusty old formy 400 to get it along
with a lot of other missing parts.

Good luck with the Car, They are fantastic to drive with or without RAM AIR, and
I can pretty much insure you'll be the only one at any show attended.

[formula kid]

RamAir was not an option in 1973 on a base formula.
Since the base engine was a 350 cid with 2bbl. and duel exhaust
It was an option on the 400 and 455 4bbl cars. Remember a 400
2bbl engine was also an option on the formula then again no ram air option on a 2bbl engine. The reason that you
Could not get the formula hood on the SD was because it had 800
cfm carb and at wide open throttle it did not pass noise standards
In California

[Brewster]

Yeap, California was ruining it for us all even back then.

[unruhjonny]

Originally Posted by whiskeyd

From everything I have read thou the ram air hood is standard on the 400 and 455 455 SD got the shaker

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I see your point of confusion;
Please allow me to elaborate.
The Formula model started out as essentially abase model with the 'base' GTO drivetrain, and a rear swaybar - in addition to some small upgrades seen on the Esprit model.

I believe that for insurance purposes, after 1970 the base Formula drivetrain was changed from a 400/4bbl to a 350/2bbl...

The key visual cue of a Formula was the distinctive fibreglass dual scooped hood.
The Formula hood could always be made functional, but from the Factory only came open/functional in one of the following ways:
1) for 1970 the Ram Air (III) engine was opted.
2) for 1971 the 'ram air hood' option needed to be selected with the 455HO engine.
3) for 1972 the 455HO engine was opted.
4) for 1973-74 the 'ram air hood' option needed to be ordered with either the 400/4bbl or 455/4bbl

The SD455 is a matter of epa(?) certification - Pontiac had the engine certified for the shaker hood - but would have needed to go through another round of (already late for the year) certification for the Formula hood.

Originally Posted by formula kid

... Remember a 400
2bbl engine was also an option on the formula then again no ram air option on a 2bbl engine. The reason that you
Could not get the formula hood on the SD was because it had 800
cfm carb and at wide open throttle it did not pass noise standards
In California

the 400-2bbl was an Esprit-only option.

regaurding your second supposition, I have read that Pontiac already had to get their engines re-certified with the EGR cheat, and never proceeded in testing the SD455 with the Formula hood.

[unruhjonny]

I would also add that, it's rarer to find these hoods unopened these days.