Thread: 80 Trans Am engine question

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I recently purchased my 1980 Trans Am and am looking for some opinions. I am planning to build a strip/street car and am looking for (obviously) a decent amount of power. My first question is how much work would be involved in swapping the PSB 301 for a PBB 455? I keep hearing people tell me it would be the best engine, but I wasn't sure what all is involved with swapping from small to big blocks. Also was wondering if it would be more effective to maybe just stick with a 400 and just keep in the small block "family"? Thanks for any help

Originally Posted by B/A T/A

I recently purchased my 1980 Trans Am and am looking for some opinions. I am planning to build a strip/street car and am looking for (obviously) a decent amount of power. My first question is how much work would be involved in swapping the PSB 301 for a PBB 455? I keep hearing people tell me it would be the best engine, but I wasn't sure what all is involved with swapping from small to big blocks. Also was wondering if it would be more effective to maybe just stick with a 400 and just keep in the small block "family"? Thanks for any help

if you want a big block, then the most power for the least amount of work would be the 454. JMO

Look at the parts on the 79 silverbird for big block hardware and it will fit right in.The 80 is still the smokey and the bandit style?

Originally Posted by lt1s10

if you want a big block, then the most power for the least amount of work would be the 454. JMO

the 454 and 455 are practically the same motor, just one is chebby and one is pontiac

Naw, the "Bandit" was a 77. The 79-81 was a different body. And as my undestanding goes, the silver bird is a very rare car. I'm obviously going to change the motor mounts (as they are older than me, haha) But i read somewhere you'de have to put differentmotor mount plates to keep the additional torque of the BB. Does that sound correct? I'm swapping out the transmission at the same time, so I'm not worried about that. Thanks everyone!

i dont know about the mount brackets about tourque handling.... if the big block mounts mount to them you should be high.... if the bolting seems a little weak, then you could either drill out and put larger bolts in or do a little welding..... if the torque is a big issue it'd be more likely that it'd be that the torque is too much for the factory rearend or also the unibody itself.... which in the case you gotta add shock tower braces, weld the shock towers, use a larger diameter sway bar and that such

Just some stuff to think about...
The "F" body cars, Firebird & Camaro are basically the same cars from 1970 to 1981 with a few minor styling and suspension changes.
The 1970 to '81 "F" bodies do not have "shock towers" to weld up or add braces to. The upper shock mounts are on the sub-frame not the body.
A set of sub-frame connectors will help with the extra torque and the stock rear will probably need some work if you want to put down the torque of the 455. A good set of gears and an Auburn posi unit would work well as would a set of CalTrac traction bars.
A Pontiac 455 and a Chevy 454 are NOT the same motors, not even close. Your 301 is a Pontiac based engine and is the same basic block as the PONTIAC 455. A 455 will bolt in on those mounts. All Pontiac motors are the same basic block configuration from the 301, 326, 350, 389, 400, 421, 428 & 455. Internals are different from size to size and year to year but a little judicious research will give you some insight.
Here is some info... There is a ton of this stuff on the internet. Do some searches...
http://www.carcraft.com/techarticles...ine/index.html
http://www.yearone.com/updatedsingle...ontengid1.html
http://www.krepower.com/

I'm with Astro, go with the 455, some frame ties and maybe even a 4 or 6 point cage. Might as well, the back seat is pretty much unusable in the F-bodies anyhow..... Depending on how much $$$$ you want to spend and how much power you want, Edelbrock makes a very nice set of aluminum heads for the poncho's. These heads along with the matching intake and cam with a good free flowing exhaust would make for a strong running torque monster.

Originally Posted by thesals

the 454 and 455 are practically the same motor, just one is chebby and one is pontiac

I know very little about a 455's, but that I don't believe.

Like I said cross reference the 79 silver bird for part numbers,because it came with the 455!!!I know all you will need will be listed on that model!!!Just because the motor mounts came on a silver bird does not mean they are 3 times the price They may be ,but crossreference the part numbers for similar parts on normal models and or cross over part numbers.I have rode in and driven the silverbird and it needs nothing more than the factory set up to scream!!!455 ,4 speed,4.11 posi,what more needs to be said!!Other than roll cage,frame ties and safety safety safety!!!!!

Swapping in a Pontiac 350/389/400/455 in place of a 301 is easy to do. It is a very popular swap since there is virtually no aftermarket for the 301.

Pontiac made "Bandit" versions of the Trans Am from 1977 all the way into 1984. The original "Bandit" movie car was actually a 1976 Trans Am with a pre-production 1977 front clip. The movie was filmed before the 1977 models were being built. There were 3 "Bandit" movies. The first used the 1976 T/A with the pre-prod front end, The second movie used a 1980 Turbo T/A, and the last one (without Burt) used a 1983 T/A. (The last movie was really bad with Jerry Reed "faking" he was the Bandit.)
The Body style of the Firebirds from 1970 thru 1981 was the same with only changes to the nose and tail thru the years. The body style change over was the 1982 Firebird.

The 326 Pontiac was not of the same block design as the other Pontiac V-8's.
It was actually designed by Buick.

Originally Posted by Oreif

The 326 Pontiac was not of the same block design as the other Pontiac V-8's.
It was actually designed by Buick.

Good info on the Bandit cars but I have to raise an issue with your 326 statement. I would like to see where you got this info... I have been building Pontiacs for years and have NEVER heard or seen this stated before. In all of my experince the 326 has been the same basic block as the bigger cubed Poncho's every time I have torn one apart.
I believe you mis-read the tech info on the Wikipedia site I listed earlier...
Read it again and realize that the "Buick" engine was dropped in favor of the iron "326"...
326
For 1963 Pontiac dropped the aluminum V8 it had offered on the Pontiac Tempest (which was built by Buick) and replaced it with a de-bored version of the standard Pontiac V8. It shared the 389's 3.75 in (95.3 mm) stroke, but its bore was reduced to 3.72 in (94.5 mm), giving it a displacement of 326 in³ (5.4 L). It was rated at 260 hp (193 kW) with a single, two-barrel carburetor. The 326 subsequently became the standard V8 engine for Tempests, and later the Pontiac Firebird, through 1967.

For 1967, its final year, a higher-output version, called the L76, had a four-barrel carb, dual exhausts, and higher compression, and was good for 285 hp (213 kW).

Originally Posted by Oreif

Swapping in a Pontiac 350/389/400/455 in place of a 301 is easy to do. It is a very popular swap since there is virtually no aftermarket for the 301.

Pontiac made "Bandit" versions of the Trans Am from 1977 all the way into 1984. The original "Bandit" movie car was actually a 1976 Trans Am with a pre-production 1977 front clip. The movie was filmed before the 1977 models were being built. There were 3 "Bandit" movies. The first used the 1976 T/A with the pre-prod front end, The second movie used a 1980 Turbo T/A, and the last one (without Burt) used a 1983 T/A. (The last movie was really bad with Jerry Reed "faking" he was the Bandit.)
The Body style of the Firebirds from 1970 thru 1981 was the same with only changes to the nose and tail thru the years. The body style change over was the 1982 Firebird.

The 326 Pontiac was not of the same block design as the other Pontiac V-8's.
It was actually designed by Buick.

Sorry but no. The original smokey and the Bandit car was a 1977 SE T/A. It was filmed in late '76. Pontiac leant the crew some cars to use before they were released to the public.

Might want to check the post date, this one is from 2006

Originally Posted by Pontiac_Man_81

Sorry but no. The original smokey and the Bandit car was a 1977 SE T/A. It was filmed in late '76. Pontiac leant the crew some cars to use before they were released to the public.

close. As I recall, the cars were actually 76 with the 77 trim. As for the car being an SE.. if you look close you can see there were a nice variety of cars used.. some autos, some standards, some large displacement, some not.