Pontiac Trans Am Shakers and Drop Bases

The Pontiac shaker was iconic on the 70's Trans Am's. When you pressed the pedal and would rev the engine it literally "shook" giving it the nickname shaker. As models years changed so did the shaker designs. Although they are very subtle, they did change. One of the most common questions we get is how to make the shaker work when upgrading or swapping the engine in the Pontiac Trans Am that has a shaker. Height and location can change and make the shaker not operable. We will outline the shakers by model year and engines so you can distinguish the differences. Unless you want to remove the shaker base system and screw it to your hood the old fashion way, we will give you the best options when it comes to swapping or upgrading your engine and keeping the functional shaker.

Pontiac Engine Shakers

1970-72 Pontiac Trans Am Shaker

1970-76 are basically the same shaker shape and size. Difference was mainly the way it attached. The 70-72 had 2 tabs with studs that went into the air cleaner and used wing nuts to attach.

1973-76 Pontiac Trans Am Shaker

1970-76 are basically the same shaker shape and size. Difference was mainly the way it attached. The 73-76 changed from 2 tabs with studs to a retainer ring.

1977-79 Pontiac Trans Am Shaker

In 1977 the shaker shape changed with a lower profile design and hard ridge line. They kept the ring and base design the same.

Note: There was an early 1977 shaker that was only 2" tall instead of the more popular 2.5" version.

Pontiac 403 Olds Engine Shakers

The 403 Olds engine shaker is the same shaker except it has a totally different base plate. The base plate is taller and has a slight offset. When swapping a Pontiac engine for your 403 the base plates must be changed or it will sit too high. More on this later.

Pontiac 301 Non-Turbo Engine Shakers

Also has the same scoop as the 1977-81. The 301 shake ring is only 14" diameter where the Pontiac is 16.5"

Pontiac 305 SBC Engine Shakers

The 305 shaker has a notch in the shaker on the side

Pontiac Engine Intake Upgrade

Pontiac intakes have different heights. When upgrading your intake you must take the height of the shaker into account or it will no longer fit under the hood. For example, the 7156 Edelbrock intake that is used in our top end kits has a height increase of 7/8". This will cause an issue unless a drop base is used. The drop base will drop the overall height of the shaker by about 1" bringing it down to the stock location. There are special circumstances when choosing to upgrade your intake. Dropping the base can interfere with some electric carb chokes and linkages. These are noted in the drop base product details. Custom linkage can be purchased or fabricated to clear the drop base. Click here to view our selection of drop bases.

Pontiac Engine Swap from 403 Olds

This is one of the most common Pontiac swaps out there, putting a traditional Pontiac back in the Trans Am. We don't cover the motor mounts in this article because that will depend on the block but we can tell you how to swap your shaker. You have two options; one is to buy a new shaker system with the Pontiac engine base plate. Year will depend on what air cleaner or drop base you will be using. If using a 70-72 air cleaner and stock height intake you would get the 70-72 Pontiac base plate. If you will use a drop base for an aftermarket intake then you would need the 73-79 Pontiac engine base plate. The second option is to remove the base plate from your existing shaker and drill and rivet it to the proper Pontiac base plate you will be using.

Both base plates and shaker systems are available from Firebird Central and Ames Performance. Links are below.

1970-72 Shaker Assembly from Firebird Central

1977-81 Shaker Assembly from Firebird Central (will also work on 73-76 but different style shaker since the 73-76 is not reproduced)