403 or 400 big block in my trans am?

Question

i got a 1979 trans am and this might be a retarded question but how can i tell what size the engine is?

Answer 1

The 403 has an oil fill neck sticking up in the front of the engine,you cant miss it.On the Pontiac engine,the oil flil is a hole in the valve cover,thats an easy way to tell.

Answer 2

if its the original engine automatic = 403 4 speed= 400

read the 6th line people I rest my case.. thumbs down really what a shadetree mechanic.. taken straight from pontiac

Beginning in 1978, Pontiac engineers reversed years of declining power by raising the compression ratio in the Pontiac 400 through the installation of different cylinder heads with smaller combustion chambers (1977 Pontiac 400 engines also had the 350 heads bolted to the 400 blocks, these heads were known as the 6x-4 heads) (taken from the Pontiac 350). This increased power by 10% for a total of 220 during the 1978–79 model years. The 400/403 options remained available until 1979, when the 400 CID engines were only available in the 4-speed transmission Trans Ams and Formulas (the engines had actually been stockpiled from 1978, when PMD had cut production of the engine). 1979 marked the 10th Anniversary of the Trans Am, and a special anniversary package was made available: silver paint with a silver leather interior. The 10th Anniversary cars also featured a special Firebird hood decal, which extended off of the hood and onto the front fenders. In 1979 Pontiac sold 116,535 Trans Ams which still holds the record to this day.

Answer 3

Pontiac did not have a Big Block or Small Block. The Pontiac 350 was available from 1968-1976 (Firebirds only). The Trans Am only came with the Pontiac 400 and 455 or Oldsmobile 403 until the Pontiac 301 was made available in 1979 and it was also available with a Turbo in 80 and 81. In 1977-1979 both the Chevy 305 and 350(California cars) were available in the Firebirds including the Formula. The 305 was also available in 80 and 81. The Oldsmobile 350 was available in 77 and 78. I hope this helps.

Answer 4

Wow, some of the answers...LOL, that's funny Mike, My 79' 10th Anniversary Trans Am has a 400 Pontiac motor in it from the factory, how does that happen if 77' was the last year they were available???

Sorry guys, had to be a smarta** on that one.

Basic Rule of thumb in 79' Automatic car= 403 Olds motor

4 speed car = 400 Pontiac motor

If it says T/A 6.6 on the shaker it's a 400 4 speed

if it says 6.6 Liter on the shaker it's a 403 automatic

The Olds motor has a oil filler neck that sticks up at the front of the motor that is very hard to miss.

Note: If you have one of the 400 4speed cars, you have a small gold mine that's worth restoring and keeping it all original.

for more info on your car, go to allgentransams.com, it's a good website with alot of knowledgable people on these cars.

for parts, go to fbodywarehouse.com, tell Pete and Heather that Jeff sent you. They are a heck of a lot better than Classic Industries and Year One.

Answer 5

You can call any GM dealers parts department and give them your vin# and they can tell you every option that your car came out of the factory with. This will include block codes that tell the exact engine that your car came out of the factory with. I believe that the eighth digit tells the block size. You can check the numbers(block code) on the engine itself. This should tell you everything about the engine even if it's not the factory engine. Being able to document that it is the original engine will help increase the cars value. Even a 1979 is starting to get rare because they were used as "stock" cars and parts are becoming rare. A company called Z&Z auto out of California was buying up all the TA and Camero parts that they could just because of this and that was ALOT of years ago. Unless your car has a 'swapped" engine, I would try to keep your car as factory as possible because of value, but if it has been modified to the point that it's not worth restoring to factory, There are a multitude of modifications and "Swaps" that you can do to that car to incredibly enhance the power train. Any Cadillac engine will bolt to that transmission. 500+ cubes at your disposal. Some modification is required, but it can be done. This will light a 79 up! It's a reasonably heavy car, but you are still talking high end of the horsepower to weight ratio.

Answer 6

79 trans ams came with a 403 oldsmobile engine.1977 i think was the last year for the pontiac 400 engine

Answer 7

The 6.6/403 Olds has an oil filler neck in front of the motor.



Here are other ways to tell the differences.



http://www.78ta.com/enginecodes.php

Answer 8

Wuick and Fast rule of thumb. Assuming everthing is original, If your shaker hood scoop says T/A 6.6, its a Pontiac 400. If it just says T/A, it's the 403.