[johnta1]

Yes.


WV 350 Manual 4bbl 068 cam 111966 dist. Tempest

WN 350 Manual 4bbl 068 cam 111966 dist. Firebird

[Cammer-6]

Im having a problem with the statement that Firebird 400HOs used standard exhaust manifolds.
Many years ago I saw a beautiful one owner 68 400HO 4 speed at a local show.
I spoke to the owner for hours,asking all I could without being a pest.
Owner told me he ordered the car as 400HO 4 speed and factory AC.
They later rejected the AC due to the 4 speed.
This car came from factory with the RA/HO manifolds.
It was also the first time I had seen wood shift knob in person,which he also ordered

Another thing that stood out was the milky sheen of the under hood black paint.
I jokingly said it looked like Armour all,to which he got a little testy."none of that crap here".

[Baron Von Zeppelin]

68 and 69 400 HO Birds got big exhaust manifolds
350 HO did not.

AC was available with 400 HO , unless they wanted steep axle ratio.
Believe 3.23 or 3.36 was steepest axle allowed with AC.

[unruhjonny]

hmm...

interesting.

I have read back and forth, and really had been unclear on this one, but recently thought I had it cleared up when I was reading an article of a one owner (unrestored) 1968 Firebird 400HO - and it showed regular manifolds.

I had thought that a one owner unrestored car was hard to refute;


/\ /\ I had thought I was seeing the standard manifolds here?

I guess I am seeing the long branch manifolds and mistaking them for standard manifolds?

If this is so, then the only difference between a (mid)1969 RAIII & 1968 400HO would be the induction(!?)

[Baron Von Zeppelin]

Adding optional Induction to 69 400 HO Bird got the functional Ram Air.

Not sure what carb and distributor packages came on 69 400 HO Birds.
RA option might have changed the carb and distributor to RA apps too - if they didn't already have those. Just don't remember

The long branch manifolds are tougher to detect from above.
But would say pretty sure those are them.

[Cammer-6]

Originally Posted by Baron Von Zeppelin

68 and 69 400 HO Birds got big exhaust manifolds
350 HO did not.

AC was available with 400 HO , unless they wanted steep axle ratio.
Believe 3.23 or 3.36 was steepest axle allowed with AC.

Take a look at the axle useage chart and sales brochure
No AC for any with 4 speed except the 1bbl OHC-6.
68 was an oddball year on restricting AC

[Kenth]

Originally Posted by Cammer-6

Take a look at the axle useage chart and sales brochure
No AC for any with 4 speed except the 1bbl OHC-6.
68 was an oddball year on restricting AC

No AC is correct for Firebird 400 H.O. 4 Speed.

GTO 400 H.O. 4 Speed w/3.23:1 gears could have AC though.

[Baron Von Zeppelin]

That is weird about the Birds. Thanks Cammer

Local friend had a loaded 68 GTO Red 4spd HO with factory AC.
It was even a Chrome Nose car too.

[muscle_collector]

i have owned a few 68 and 69 HO birds (still own one sold new here in town) and surprisingly everyone of them i bought from original owners and everyone of them had long branch manifolds.

[Tellyshavilli]

Same here all the 68 & 69 Firebird 400 HO cars we’ve owned had the long exhaust manifolds and the 69 400 HOs 4 Spd always had the 7029263 carburetor Carter built

[Mcronk]

Interesting note on the 7028273 and 7028270 carbs. They first appeared on the 68 RA I (late) and RA II engines. They are also listed for the 69 RAIII engines according to the GTO Association Illustrated Indentification Guide (Eric Whites book). The 69 RAIV engine was 7029270 and 7029273. Normally the 4th digit is the last digit of the year in this era. Is the book wrong?

[unruhjonny]

As I mentioned earlier in this discussion (and Baron seemed to confirm) the 1968 D-port ‘Ram Air’ engine never came with the 7028270/7028273 carbs;
These application numbers were introduced with the “Late” ‘Ram Air’ engine, which we now refer to as the RAII.

To try to clearly say this another way, those application number Quadrajets were only used in 1968 with the round-port ‘Ram Air’ engines.

Some literature refers to the RAII as “1968.5 Ram Air” or “1968 Ram Air (late)”.

Yes, the fourth digit on “70” Quadrajet application numbers does normally indicate model year, but these two application numbers were two of a few exceptions;
These application number carbs were carried forward and used on some early 1969 RA cars.

I cannot speak as to if they were only used on RAIII vs RAIV engines, because I do not know this.

[Baron Von Zeppelin]

The 8270 & 8273 were used on all the Ram3 engines up through at least Feb 69 production.
The 69 units had the date codes stamped into the baseplates.

Something went goofy about Ram3 and Ram4 production releases.
The Ram3 didn't start going out until around late November-December
The Ram4 didn't start going out until around late Jan-Feb
And that just applies to GTO's

The Judges were another month or so behind those dates in both respects.
I think the first Ram4 Judge known is around late Feb or early March

Its all weird.
Best guesses are maybe the Induction set ups weren't finished yet.
We know the Ram3 Judges were timed/planned releases.
But why the Ram4 Judges were prolonged is odd , maybe they wanted all the Ram3 Pattern Judges gone first.

[Kenth]

I have found the 69 units had the date codes stamped onto the baseplates only until mid-Dec 1968.

[Mcronk]

This is why I like this site. Lots of information that is from folks who are very familiar with these cars. Regarding the 270 and 273 carb usage in 1968, I have found the GTO Association Identification Guide to be one of the most accurate resources. Attached are pictures of the section on 1968 carbs. It very distinctly lists the 270 and 273 as late RA (L67) usage and seperately lists the carbs for RAII (L67) engine. The explanation of late meaning RAII engine and early meaning RA engine could explain the confusion. It is possible while collecting and compiling this data it could have been interpreted differently and those carbs were listed for both the RA and RAII engines. We also know even the factory made mistakes in their documentation. I am not challenging anyone only trying to understand which is correct? Has anyone with a RA car that had/has original carb verified a 270 or 273 carb? The information in the Guide had to be compiled from other sources so I expect there is factory documentation that lists carb and engine applications. Other information I have lists the 274 and 275 as the RA carbs. If the Guide is wrong I want to make a note to correct it. Thanks.

[unruhjonny]

that book is wrong.

the "late" 1968 Ram Air IS the round port RAII;
L67 is the regular production order code for the Ram Air engines - and when the D-port Ram Air engine was replaced, the round-port Ram Air engine WAS the only Ram Air engine.

It is well known that for 1967 that the Firebird Ram Air Quadrajets had tabs on the throttle body which limited the ability to go wide open;
If the throttle bodies were different, then it makes sense to do different application numbers between Firebird 400 and GTO - except in 1968 the tabs were no longer there - my guess is that PMD intended to have the tabs present on the 1968 Quadrajets, but didn't.
For the RAI there are four application numbers of Quadrajets, and interestingly, they all had one service replacement application number (this serves to suggest that PMD knew that the Firebird 400 & GTO Quadrajets were the same thing). That service replacement was a number previously for a Firebird 400 - 7028276. (I am surprised that the guide makes no mention of this.)
The different Firebird 400 vs GTO carburetor application numbers simply went away with the "late" Ram Air engine - both body styles used the same application numbers.

I believe (don't have literature handy) that the 1968 applications of the 7028270/7028273 also used the 7028276 SR carb;
I believe that the 1969 applications of the 7028270/7028273 used the 7029270 as the SR carb.

I had understood that 1967 & some 1968 Quadrajets had issues with the quality of the casting on the fuel bowl, which was the reason so few of those original carburetors exist today.

Additionally, that book doesn't list the two casting numbers of intake manifolds used in 1968;
I believe (going off memory here) the change over was somewhere just before the introduction of the RAII.
All RAII engines should have the later casting intake manifold.
'early' intake manifold: 9790140
'late' intake manifold: 9794234

The late intake manifold had the same size runners as the prior D-port engines, and was NOT the taller runners that the RAIV & 455HO/SD455 used.

For a brief time, my cousin had what may have been the very latest built RAI Firebird; it had the later intake manifold casting number.

[OG68]

Originally Posted by unruhjonny

Additionally, that book doesn't list the two casting numbers of intake manifolds used in 1968;
I believe (going off memory here) the change over was somewhere just before the introduction of the RAII.
All RAII engines should have the later casting intake manifold.
'early' intake manifold: 9790140
'late' intake manifold: 9794234

The late intake manifold had the same size runners as the prior D-port engines, and was NOT the taller runners that the RAIV & 455HO/SD455 used.

For a brief time, my cousin had what may have been the very latest built RAI Firebird; it had the later intake manifold casting number.

From what I've seen while looking for a date correct manifold, was the changeover date was around March 16-18.

[unruhjonny]

Originally Posted by OG68

From what I've seen while looking for a date correct manifold, was the changeover date was around March 16-18.

Incase you hadn't noticed, that GTOA guide didn't even list the first casting number, so for the anal retentive judges who might use that as their "bible" (because we all know some show judges are that way), all cars assembled before that date with their original intake would be deemed to have the "wrong" intake - LOL

[OG68]

It's noted in Updated Information (dated Oct 2009) at the first page of the book.

[Mcronk]

Regarding the change over date for RAII production pieces Jim Mino told me the earliest dates he had found for specific RAII parts was March 11, 1968. He said the parts were done in batches not a continuous run through end of production. I have a WY RAII block cast on April 28, 1968. Intake 9794234 dated May 1, 1968. My RA II GTO was invoiced May 31, 1968.