Firebird and the Trans-Am series

[tjs44]

inside X ram

[crazyamc]

Big applause! I LOVE to see the obscure parts posted! THANK YOU!  I have two questions; the offset on the carbs looks like they go the wrong way, (meaning it seems to me that they're sitting at the ends of the plenums..?   2.  The roof of the opening; was the distribution fixes and the cut away roof cast that way, or was it a 'dyno' mod?  Ken

[tjs44]

You have to realize the intake port arrangement is more like a BBC than a SBC,meaning no paired ports.To balance the flo they must have had  proof that it was better to have the carbs positioned where they are.I like a tunnel ram myself over a X ram.Pontiac had a factory tunnel ram avail over the counter for their 421 SD program way back in 1962.Tom

[mike343sharpstick]

I remembered seeing this attached info elsewhere on THIS forum. There is so much information here on misc. TA cars and related engine technology it's incredible.
Note the picture on the upper-left, you can see where they are testing different carb configurations.

[69Z28-RS]

I didn't know much about Pontiac's '303' engine, so I had to do some digging.  I was curious about the bore/stroke relationship.. and for us 'over square' engine lovers (who love revs), all I can say is WOW...   Does anyone have an audio clip of this engine at 8-9 grand??
Has any factory engine ever had a higher bore/stroke ratio than 4.125/2.84= 1.45 ?
"303 specs...


The 303's bore was identical to the 400 at 4.125 inches, but it featured a shorter stroke at 2.84 inches. The 303's short deck took off about 40 lbs. from the 400 V-8 version.  The racing 303 was equipped with four-bolt mains, a forged steel crankshaft, aluminum intake and a high-rpm crankshaft that allowed the engine to rev up to a whopping 8,000 revolutions per minute. Pontiac beefed up the main-bearing webbing to handle the high revs and reinforced the ribbing. The engine was a Ram Air forced induction model with Ram Air V heads and R/A-V cast-iron exhaust manifolds. The compression ratio was set at 10.75-to-1, and with an 800 cfm four-barrel Holley carburetor, it generated up to 525 horsepower. The intended production version, which would satisfy the SCCA homologation rules, would generate 355 horsepower."

[ko-lek-tor]

Dag Gawn, that's impressive!! I'm with you Gary, I want to hear one of those Indians 8K wail! Like you, I am going to read up on the 303 thanks to this post. Thanks guys and CRG.

[Jon Mello]

I feel like I should be wearing a helmet and cape while posting these. Here are a couple of photos from Mike Scott, aka group/7. They are of a spectator's car in the parking lot at the 1970 Mosport Can-Am. I thought those trunk lid rear wings only came around as a result of the Fast & Furious films but here is the grand daddy of them all. Firebird GT47 rules! 

[satman]

I worked for a Canadian GM dealership back in the sixties and trust me there never was a factory built Firebird with a Chev engine but I guess the overworked tech staff decided to let it slide. In my opinion the Firebirds were not that well prepared and needed all the help they could get.

Al Richards

[Jon Mello]

Al, there was a Firebird made within Pontiac somewhere that did have a Chevy engine installed in it and it was taken up to Terry Godsall's dealership in Canada as a ploy to convince the SCCA people that some Firebirds were equipped with Chevy engines north of the border. I do not think the Chevy engine was installed on the assembly line but I do think some paperwork was created to make the car appear legit. I don't think any of it was truly necessary as SCCA was willing to look the other way just to get Pontiac's involvement.

[Jon Mello]

Here's another picture of a '67 Firebird at the Mosport circuit, courtesy of Mike Scott (group/7). This shot was taken at the
1000K enduro in August 1984. No other known details about it. I don't recall another car trying to take aerodynamics to
that extreme on that style of body back in that era.

[1109RWHP]

I am glad that trend never caught on, at least over here. Japan has cars like that running around.

[Jon Mello]

I agree. That's not a look that does anything for me.

[firstgenaddict]

Here is an early configuration of Titus's 69 car, it has a duct taped 68 front bumper on a 69 styled body

https://revslib.stanford.edu/catalog/nc991hs6427

Better pic of the front end

https://revslib.stanford.edu/catalog/hx133kv3882

[Swede70]

Greetings,

Now for something completely different!  See link to pdf file of a Japanese motor racing magazine examination of the '69 T-G Racing Firebird Trans Am/SCCA Trans-Am effort.  I'd never seen the photo image depicting a Superbird/Charger Daytona high wing (plus discreet vents/bubbles on the top of each fender consistent with reproducing the concept entire) on the 1969 prototype before, hence something surely to mull.  Wait! - when was the Charger Daytona developed, and who was Paul Lamar befriending and chumming around with in period?  Fun regardless, and an alternative conception of Stardust memories...

http://www.rotaryeng.net/Japanese-TransAm.pdf

Mike K.

[JoeC]

I don't know if this has been posted but there is some interesting Firebird TA stuff here

http://musclecarfilms.com/1969_Firebird_Engineering_Cars_2.html