The inception of GM Performance Parts started in the late 1960’s when a then-27-year-old Ernie Callard was invited to a high-level GM Directors meeting to discuss the factory support needed for various Trans Am racing teams. The directors themselves had two concerns: Where do they store the parts, and how do they ship the parts? Above all, Callard was instructed to never run out of parts for the GM teams. With those directions, Callard was put in charge of a new line of high performance GM Parts. Initially, the parts were planned to be “no code” parts so that no one could track what they were, where they were going, or who finally received them. Ahead of his time, Callard had a slightly different idea: “I told them, ‘Let’s put a number on the parts. Let’s sell them! Let’s make these parts available to anyone who wants them for their own cars!’” The GM executives agreed, and Callard found himself in the high performance parts business. Although it’s doubtful that he knew it at the time, Callard’s early concepts of high performance part numbering, configuration, packaging, and distribution initiated the concept of a “crate engine,” while simultaneously laying the groundwork for what are known today as GM Performance Parts.

Soon, high performance fans were buying up speed parts to enhance the performance of their Corvettes, Camaros, Novas, Impalas, or Hot Rods. “GM built many more engines than vehicles that were sold,” explains Callard. “So we grabbed up the remainder, put them into crates, and sold them as the first ‘crate engines.’” By 1970, the crate engine line was in full swing, much to the delight of hungry consumers, eager to take advantage of the new resources. In 1989, the first GM Performance Parts catalog hit the GM dealer’s counters. Now, dedicated performance engines could be ordered “in the crate” and the floodgates were open. The decade of the ‘90s began an era of extreme growth in the performance parts business, which still continues today.

The turn-key peace of mind that comes with installing a crate engine is well worth the hassle of installing one, which can still be a very frustrating task. Today, we look at installing an LS3 into a 1970 Chevrolet Caprice. One of the advantages to this engine swap is that we can shave off as much as 850 pounds of combined drive train weight while installing modern technology that will give the Caprice the efficiency, power, and reliability of a new car.

As these engines have become available through local dealerships and directly from GM Performance, the word has spread about their advantages to auto enthusiasts, making the LS transplants increasingly popular. Thanks to these engines’ reliability, popularity, and aftermarket support, automotive enthusiasts have been installing them into everything from Mazda RX-7s to Nissan 240s, and in our case today, a 1970 Caprice. On this build, we have been able to get advice from some of our friends and insiders within the industry, helping us to avoid the usual pitfalls that can come with these installs. Now follow along, as we prep this LS3 for a transplant.

1. This LS3 was ready to be assembled.

2. The first item on the agenda was to put
our engine on our Harbor Freight heavy duty
engine stand. When putting your engine on
the stand, make sure that you are using metric
bolts as these LS motors are completely metric.

3. Energy suspension offers chrome motor
mounts that will place your mounting point to
a stock location.

4. We test fitted our energy suspension motor
mounts, which put the motor mounts back in
the 350 motor mount position.

5. Once we bolted on the motor mounts, we
realized that these mounts needed to be
replaced, as they would be blocking the factory
pulley set up, and would not work without being modified. Some manufacturers offer different
spacings for different applications ranging
from stock 350 to 3 inches forward, depending
on your vehicle.

6. This stud bolt was installed and will help to hold the weight of the AC compressor when it is time to install it.

7. The AC compressors cradle was bolted up.

8. GM Performance makes the install easy as
they number everything individually, in order
to help make the install as easy as possible.

9. These four bolts kept the AC in place.

10. Since the compressor ran separately, it
received its own tensioner.

11. The pulley slipped on with ease.

12. With the factory water pump bolted on,
we were ready to add the alternator and power
steering unit.

13. The pulley bracket went on with ease.

14. With a couple of turns of the ratchet, the
bracket was bolted up.

15. We laid out the power steering in order to
make sense of how it bolts on. This would make
sure that the rubber hose wouldn’t bind up,
starving the pump.

16. We clipped the reservoir in place and bolted
down the power steering pump as one unit.

17. Two bolts held the alternator in place and
only needed to be tightened by hand before
they were tightened down with a torque

18. The drive was ready to receive a belt once
the belt tensioner was bolted up.

19. The factory belt tensioner was installed,
and the purpose of it is to keep the belt from
slipping when running high RPMs.

20. The main belt was put on and went on with

21. To make sure of our clearances, we
mounted the starter.

22. The motor was ready to be installed and
mocked into our car. Make sure to follow this
step a few times to assure that the motor is
installed properly.