Third Gen Camaro Ignition Wiring Diagrams

Years ago, installing an LS engine between the front fenders of first- or second-generation F-Body car was a challenging endeavor. That is no longer the case because aftermarket engine mounts, transmission crossmembers, and peripheral equipment are now readily available for about any combination. When swapping an LS engine into a 30- to 45-year old F-Body, you're integrating some of the latest GM engine technology into a vintage car, so it's not just bolting the engine to the subframe. An LS engine swap into an F-Body goes far beyond that. It's installing a complete performance package that's compatible with F-Body chassis. As a result, the LS engine, transmission, suspension, brakes, wheels, and tires all have to be compatible at the minimum; and complementary for maximum performance.

This Tech Tip is From the Full Book, SWAP LS ENGINES INTO CAMAROS & FIREBIRDS: 1967-1981. For a comprehensive guide on this entire subject you can visit this link:

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Before you mount the engine on a hoist and prepare to install it, also select the engine mounts, adapter plates, transmission crossmember, headers, and oil pan because these are part of a package. Although experienced swappers can use parts from multiple brands and essentially piece together their own engine mount kit, I recommend you purchase a complete swap kit from a single manufacturer. By doing it this way, you have compatible parts and make the install much easier because you won't have fitment issues from mixing and matching parts. Holley, Street & Performance, Energy Suspension, Autokraft, and Turn Key Engine Supply offer kits for LS engine swaps into early F-Bodies.

Mary's LS3 drops right in as if it were meant to be there all along. (Photo Courtesy Mary Pozzi)

The installation of an LS engine can be done in the typical garage with jack stands, a solid and reliable engine hoist, and a host of typical hand tools. I recommend that you use a load balancer because it's easier to position the engine while installing it on the frame rails. A load balancer is particularly helpful when keeping the front sheet metal, which includes fenders, front fascia, and grille. It's needed especially if you are installing the transmission and engine together as one unit, as I chose to do. It's cheap and safe insurance for your well-being and to keep your investment.

This LS engine was installed in Mary Pozzi's second-generation Camaro. (Photo Courtesy Mary Pozzi)

Mary prefers to install her engines without the transmission. It makes for a lot more wiggle room up front and reduces dings and other costly errors. (Photo Courtesy Mary Pozzi)

At this stage, you've carefully considered and determined your application, so you've selected your engine and determined the setup. Now you need to figure out which transmission you're going to use. Virtually any one on the market is compatible with an LS, so you have to narrow it down. The good news is that you won't have to modify the transmission tunnel in most cases. I say "most cases" because many first and second-generation F-Body cars are close in specification, but the operative word is "close." The tolerances can vary widely from one body to the next. The only exception that I am aware of is the 4L80E transmission; it is typically quite large and in most cases needs a transmission tunnel adjustment.

Front Clip Sheet Metal

When swapping an LS engine into your first- or second-generation F-body, remove the front clip sheet metal so you have easier access to the front subframe for mounting the engine. In addition, won't risk damaging the valuable sheet metal when installing your new LS power plant. While removing the sheet metal isn't a requirement to install the LS, it has many advantages as discussed, and I had my own reasons. For one, I did this for demonstration purposes as detailed later. Also, I removed the front sheet metal because I'm going to change the subframe in the near future, and it makes the install much easier in the long run if I do this step first. Keep in mind that if you remove the front end, you need to realign all the panels for gap and proper fit when the parts are reinstalled.

Every project has to start with a first step. As with any engine-swapping project, you need to remove the hood before the real work begins.

All you do is remove four bolts and have an extra pair of hands to help take off the hood.

Several bolts secure the front sheet metal to the frame, and you need to remove the bolts and carefully support the front fenders when removing them. To remove the front sheet-metal bodywork, use a simple socket set with a fair amount of WD-40 and a couple of buddies who can help you lift the front clip off.

When it comes time to separate the bodywork from the frame, get some friends to help lift off the sheet metal. You need to carefully and methodically remove the sheet metal because you don't want to damage it. When you're performing a swap project, you don't want the expense or hassle of performing bodywork because the sheet metal was tweaked or damaged during removal. Although the liftoff procedure can be done with three people, a fourth person makes the job easier to complete because that person can help resolve any unforeseen snags and hang-ups, such as removing missed bolts or disconnecting wiring and hoses. Oftentimes, the "spotter" is the vehicle owner, as was the case here.

Two 1/2-inch bolts hold the core support to the front subframe. As you can see here, mine suffered under years of rust so it had to be cut out with a reciprocating saw. This is just one aspect of working on rusty old cars. Unfortunately, the massive body bolt was in a hard-to-reach location. The fastener lubricant didn't help budge the bolt and eventually I rounded off the head, leaving only one option: cut the bolt out.

You and a couple of buddies can quickly and easily pull the entire front sheet metal off the car. I used simple sockets to remove the bolts. Most of them are 1/2- or 9/16-inch so keep a couple of those sockets handy. Carefully remove the bolts. While you don't have to support the bodywork as it's being removed, you need to have help when doing this work. Make sure all the electrical harness connections, such as the headlamp, marker, horn, relay, etc., have been removed before lift off. The front fenders and front valance can be removed (and then re-installed) in one piece, making access very easy. This is the best way to make your Mustang friends jealous.

The A/C pump location can present a major problem clearance problem with frame and/or body. I can either remove the A/C bracket and pump or notch the frame. I chose to relocate the A/C unit. You can jump to the chapter on front-drive accessories and see how I fixed the problem. When presented with this issue, Mark Stielow chose to notch his frame to make room for his LS9.

Spend the time to make sure all the bolts and fasteners that connect the sheet metal to the chassis have been removed, so you save on the frustration and hassle. Remove a few bolts so the front end can be separated from the rest of the chassis. Several bolts hold the front clip to the subframe and firewall. In fact, several bolts connect to the firewall and the inner fender well bolts. Use a 9/16- and 1/2-inch socket and ratchet to remove these bolts.

Be sure to disconnect important components, such as the front wiring, ground wires, hoses, and anything else that might get in your way. I found it easier to disconnect the front wiring harness at the firewall, which is just under the brake booster and held in by a solitary bolt.

After removing the battery tray, you see one of the six main body mount bolts that hold on the sheet metal. Removing the battery tray and body mount bolts is a simple procedure using the appropriate sockets and wrenches. In this case I had to cut one of them off with a reciprocating saw due to rust. I had the misfortune of running into a seized bolt that rounded off when I took an impact gun to it. I took this opportunity to buy new tools and cut the bolt off. Another body mount bolt is located on the driver's side. While performing this procedure, it's wise to replace the stock body mounts with either stock replacements or, in this case, solid aluminum mounts that work together with the Speed Tech subframe. These mounts keep the body securely supported and work just as well on the aftermarket subframe as they do on a stock subframe. They are the same size and shape as the stock versions but are completely solid.

Two bolts fasten the two fenders to the firewall. These are easier to access if you remove the hood hinges.

In addition, you need to remove the bolts that hold the inner fender wells in place. The mounting bolts on the passenger's side were accessed through the engine compartment while the driver's side was less complicated if I removed the bolts from the inside of the fender. In addition, there are two lower bolts holding the front fenders to the body. These are located just in front of the rocker panels and are underneath the car held on with J-clips.

At this stage, the front-end sheet metal should be removed from your F-Body. When you're disassembling the body, bag and label all the bolts and spacers you have removed. It saves time and reduces hassle during reassembly and when aligning the body panels. The front tires should be removed before lifting off the front clip because it allows plenty of legroom and enough room to guide the fenders off. One key tip: Make sure the lower part of the fender has enough clearance to release itself; this is a good job for the spotter as it's his paint job.

Stock Subframe

You can certainly retain the stock subframe for an LS swap in your first or second-gen F-Body. If you choose to use the stock subframe, you need a few special parts to make it work properly, so don't let that deter you from making a clean install. These parts include special engine mount adapters, a new location for the transmission crossmember, and a set of headers designed for the LS series of engines in either the first- or second-generation F-Body.

Before installing the LS engine in an F-Body subframe, carefully and methodically remove the wiring harness from the chassis because you don't want to leave it connected to the chassis and damage it when installing the engine. While it is entirely possible to install the engine with the wiring harness in position, it's best just to remove it to avoid any possible damage.

A slight issue I had was the clearance of the sway bar. It didn't touch but this is certainly too close for comfort. You may have to purchase an aftermarket sway bar or carefully bend yours to make it fit better. An alternative method is to add spacer blocks between the inboard sway bar bushings and the subframe. This drops the front of the sway bar for clearance. If you use the stock subframe, you have to purchase a suitable aftermarket sway bar with more clearance. Some installers notch the sway bar but that's usually not a good idea unless you are very confident in your welding and fabrication skills. Instead, using a dropped pitman setup is often a much better choice.

Without a distributor the engine has a lot more breathing room. You may find that you have more room between the firewall and the engine than you anticipated. This is a common problem that can be solved with relocating the mounts and moving the engine forward enough from the firewall. Adjustable mounts can be helpful but aren't always necessary.

My new slim brake booster and master cylinder from Matt's Classic Bowties provides ample line pressure and does not contact the new engine. I finished off the brake system with a pre-bent stainless kit from Speed Tech that is a simple bolt-on and screwin type of setup. These pre-bent lines need some finesse as are maneuvered around parts such as the frame and steering components. The lines are sensitive so do not force them while routing; if you do, they can kink. Brake lines aren't paramount to an LS swap as stock ones work just fine.

When the transmission is connected to the LS engine, its bellhousing sits much closer to the cylinder heads than in the Gen I small-block engines so your LS engine sits nearly flush with the firewall. As a result you have a few clearance issues to resolve. The valve cover clearance is very tight and often a valve cover interferes with the heater hose outlets on the firewall. Not only does this cause an issue with typical engine movement during normal operations, but it also makes it almost impossible to route heater hoses. To resolve this problem, you can install a 1969 Camaro big-block heater box and heater core because this repositions outlet fittings so the hoses clear the valve covers. Make sure to get the correct model for your application. The first generation versions are all the same but the second-generation cars use a different design.

I noticed some pretty tight clearances with the heater outlets. If you are having issues with this, a quick fix is to get a heater core for a big-block. This is the simple and easy solution to this common problem. I recommend replacing the heater core because you have easy access to it at this stage.

As you can see, with the front sheet metal off, removing the old engine is a whole lot easier.

The stock brake booster is often too big and crowds the factory LS ignition coils on the valve covers. Replacing the brake booster with a smaller housing is another effective solution, especially if you are going to keep the stock or similar brake package.

A series of bolts fastens the front fenders. These are the two that hold the inner and outer fender onto the firewall and cowl positions. The front upper and lower valance support the front fenders. The rear part of the assembly may be a bit wobbly, so make sure you have friends to help keep the front clip from twisting.

The driver-side and passenger-side fenders are a bit different and are asymmetrical in how they attach to the car. On the driver's side, three bolts and three large washers connect to an outstretched arm to the inside of the fender. These are relatively easy to access.

The arrow in the center of this image points to the body mount bolthole.

Installing a coil-relocation kit and moving the coils is one option. Many companies offer relocation kits. In fact, ATS sells a kit that allows the coils to be moved to the underside of the engine, making them virtually invisible. It features a set of custom-made brackets that allow you to put the coils in any number of locations, including the back of the heads so you have many options for mounting the coils. This kit works with LS3 coils and gives the engine a clean, uncluttered look. Keep in mind what type of brakes you'll be using as a small booster generally means less brake assist. I was able to find a much smaller, 8-inch dual-diaphragm version that I sourced from Matt's Classic Bowties. I also used a 7/8-inch master cylinder that provides enough line pressure to provide the clamping force needed for the six-piston Baer calipers.

The inner passenger-side fender is a mirror image of the inner driver-side fender. On the passenger's side, it's easier to remove these two bolts than the three on the driver's side.

By now, you should have all the bolts for the front sheet metal removed. Doublecheck to see if any remaining parts are still attached and formulate a removal plan. Don't forget the little bolt on each side that holds the lower part of the outer fender onto the car, so it doesn't flap around in the wind.

The stock brake booster is way too big and doesn't clear the valve covers and coils so it needs to be replaced with a more compact aftermarket brake booster. I replaced mine with an 8-inch booster from mattsclassicbowties.com. I also have to run a smaller-bore master cylinder for the upgraded brakes. A popular Pro- Touring mod is to run a nonpower-brake master cylinder. They have a lot better pedal feel when under hard braking.

For my particular engine swap, the stock steering linkage was retained so maneuvering the engine into position under the hood and aligning it with the frame rails was a real challenge. I had to inch my way forward with the LS3/T56 transmission. If the T56 had not been mated to the engine, this procedure might have been a lot easier. A lot of finessing went into using the stock frame mounts and the ATS engine mounts. I often had to lower the engine a fraction of an inch then push it forward to make any progress.

LSB

The engine hoist securely supported the engine and transmission combination, but that can't be said for the chain-to-hoist link, which gave out at the last possible second. I had a friend help me with the procedure moving the engine down and back over and over again. You could in theory do this alone in your shop, as I had to do many times before. It helps to make the install go that much more smoothly with an extra pair of hands and eyes to guide things into place safely. This method had to be repeated many times to get it just right. While I didn't get a photo of the process, I did use a jack to support and guide the transmission into place. It seemed to help balance the load and provide a fair amount of stability when guiding the engine into place.

Aftermarket Subframe Installation

Step 1:

sa245_fullbook_lsswaps_page_033_image_0001 When you install an LS engine in a stock chassis, all the lines are out of the way and the transmission crossmember is in place for easier install. The crossmember needs to be relocated in most applications depending on your transmission choice. Therefore, you need to use aftermarket engine mounts.

Step 2:

sa245_fullbook_lsswaps_page_033_image_0002 My engine is about to be slotted into position. Removing the front sheet metal makes it a lot easier to install and get at things. It doesn't take up that much time when all things are considered. I was able to get it in place by alternately lowering it and then pushing it back inch by inch. I used an engine hoist and a buddy to help guide it into place. Repeated movements in small increments are required to get the engine into its final position.

Step 3:

sa245_fullbook_lsswaps_page_033_image_0003 My LS3 is safely and securely in place. I had to do this very carefully because of the transmission being in place; you may have to remove the transmission. The Mast oil pan fi ts quite well with the stock steering linkages. There are a number of other oil pans that may fit your needs.

Step 4:

sa245_fullbook_lsswaps_page_033_image_0004 Here's the passengerside frame bolt, fuel line, and ground strap. Make sure to clear these two objects when removing the bolt. This frame mount looks as if it has seen better days, so it should be replaced.

Step 5:

sa245_fullbook_lsswaps_page_033_image_0005 The steering rod's rag joint is often forgotten when separating the subframe from the body. The rag joint is held together by two bolts and should just come right apart. Mine is worn out and really needs a new one. (I will replace it with a solid joint later.)

Step 6:

sa245_fullbook_lsswaps_page_034_image_0002 When using stock parts, it's best to just replace them. I cut out certain pieces, such as this brake line, because I planned ahead and knew I was going to replace them.

Step 7:

sa245_fullbook_lsswaps_page_034_image_0004 These body mounts are severely worn and must be replaced. If you haven't done this yet, it's a good idea not only for performance but for ride quality too. The new bushings install just like the old ones; put them in place before setting the body over the frame.

Step 8:

sa245_fullbook_lsswaps_page_034_image_0001 Support the body with jack stands and make sure the jack stands are securely positioned. Remove the four body bolts from the frame and separate the body. Do this slowly and carefully. I used a jack and a block of wood to move one side of the body at a time. I then used a series of strategically placed jack stands to keep the body level and give me room to slide the new subframe into place. Although it may seem that the body is stable, you don't want the jack stands to slip and compromise safety.

Step 9:

sa245_fullbook_lsswaps_page_034_image_0003 After you drag out the old subframe, you are left with really good access to the car. This is the best time to repair any holes and add a fresh coat of paint.

Step 10:

I followed Speed Tech's recommendation and installed their solid body mount kit. The body mounts install just like the stock ones: Place them in their location and drop the body onto the frame making sure to use the corresponding mount from the bottom of the frame. The little rings on the mounts ensure each one goes in the correct place. Speed Tech supplies all the Grade-8 hardware to complete the job. You could go with the stock rubber mounts, but considering the amount of work it takes to replace them, I felt it best to just use solid ones and be done with this project for life.

Step 11:

sa245_fullbook_lsswaps_page_035_image_0001 With the wheels mounted to the subframe, I was able to roll the frame under the car with the engine and transmission already attached. It allowed me to maneuver the subframe into place and square up the car. I then used a jack to tip the front of the car down enough to match the angle of the subframe. My brother-in-law Erik helped me align the frame and subframe. Using the alignment holes on the middle body mount, I made sure it was as square as possible before heading out to the alignment rack. A long screwdriver or a dowel helps align the frame fore and aft and you shouldn't need any special tools to get it square; these holes are sufficient. Later at the alignment rack I found out that I was .1 degree within complete square of the car, so using this procedure is extremely accurate. Four massive frame bolts installed and the job was complete in less than half an hour with the aid of a good buddy

Step 12:

sa245_fullbook_lsswaps_page_035_image_0002 You can see the lines on the frame mounts to indicate which is which. The lower half (far right) mates perfectly with the upper half (left and middle) to form a solid place to mount the car. The frame mounts have rings around them. In this case they match up to make the correct mate. For example, some have two rings, some have three, and the others have one ring.

Engine Mounts:

An LS engine swap, in reality, starts from the bottom up and engine mounts are quite possibly the most important piece of the entire swap process. The correct positioning of the engine and fitment of the radiator, headers, exhaust, hoses, wiring, and other components is critical for performance and reliability. You need to select the engine mounts and adapter plates while taking the rest of the engine package into consideration. In other words, when you select the engine mounts and adapter plates, contact the manufacturer to make sure that the oil pan, headers, accessories, and other parts you plan to use are compatible with the engine mount package.

Be sure to follow the manufacturer's instructions for mounting the engine in the chassis because different manufacturers have different mounting locations for the engine. If the engine isn't correctly mounted on the frame, some of the parts, such as the exhaust, hoses, and steering rod may not fit. It may be difficult to correctly align the driveshaft for the rear axle assembly. The transmission crossmember location, the header fit, the amount of room for a radiator and fan combination, the clearance of your oil pan and the front-drive kit all rely on the correct mounting and placement of the engine. This highlights a major point that I make throughout this book, which is the importance of coordination and careful planning. A matching engine mount and header combination is your best ally when doing this swap.

Make Your Own Engine Mounts

Making your own engine mounts is a bit daunting. That used to be the only option when installing the LS engine into first and second generation F-Bodies. Thankfully, the aftermarket has come to the rescue to solve this simple, yet important part of the swap.

As mentioned previously, externally all LS engines are virtually identical, and this holds true for the engine mount location. The four bolts holding on the mount are all in the same spot and have the same spacing, so the same mounts you would use for an LS1 fit every other iteration in the LS family. The four mounting bolt locations are slightly forward of the engine centerline when viewing it from either driver's or passenger's side.

When swapping an LS engine into an F-Body car, often the transmission does not line up with the mounts while the stock engine aligns perfectly with the mounts when installed. One reason may be the engine mounts you just swapped in are not compatible. The Gen I small-block has a 13 ⁄8-inch area that extends beyond the rear part of the passenger-side cylinder head where the transmission bellhousing bolts to the engine block. The Gen III/IV LS series has a scant .060-inch area that comes out of the same area where the bellhousing meets the block.

There are many types of engine mounts, but as a starting point, you need to determine the type of engine mounts you have on the engine and frame. Just because your F-Body came with a small-block, it doesn't mean the engine mounts and frame mounts are the same. Tall and short smallblock frame mounts have been used. General Motors installed two different heights of mounts on F-Body cars. One type was designed for high-performance cars while the other was designed for common road cars. The high-performance versions, designed for the Z/28 and other cars, were lefthand 35 ⁄8 inches and right-hand 33 ⁄4 inches. An engine-mount thickness of 21 ⁄8 inch helps achieve the correct engine mount height. The common F-Body 4- and 6-cylinder mounts are 311⁄16 inches for left-hand mounts and 315⁄16 inches for right-hand mounts. The mounts are 15 ⁄8 inches thick. The difference between these two numbers is the height. To order the correct parts, be sure to select the correct size and shape of engine mounts for your chassis.

Many companies make engine mounts for an LS swap into 1967– 1981 Camaros as well as a host of other vehicles. Motor mounts are relatively inexpensive and can be ordered in just about any combination and shape. Typically, a good quality set of engine mounts sells for about $150 and slightly more for higher quality sets so you shouldn't have to fabricate a set of your own but that is always an option.

You can fabricate your own out of 1/4-inch plate steel, but it's not worth the time and effort. Engine mounts are inexpensive and readily available. Most complete kits come with Energy Suspension polyurethane Chevy engine mounts. These mounts are the small-block standard of the three bolts. The major difference between manufacturers seems to be materials and finish of the engine mounts. Some are made of aluminum while others are plate steel.

For most LS engine swaps into F-Body cars, you can use the stock mounting locations. You should trial fit the engine in the frame. If the sheet metal has been removed, it makes the process much easier. With the engine on a cherry picker, align the engine mounts with the chassis mounts. If it properly aligns and clears the firewall, your job is much easier. However, it doesn't always work out that way. Sometimes the engine needs to be set back, forward mounted, or to have adjustable mounts. Because of inconsistent and inadequate quality control at the factory in the late 1960s and early 1970s, some cars can be as much as 1/2-inch off from another F-Body car. It means that not all parts are going to fit exactly as designed.

As I've been told, you "have to think like a hot-rodder," and that means you need to think and work through a problem. Sometimes that means having to tweak things to make them fit. So, with that said, there is no single engine mount I can recommend for all engines and F-Body chassis. As a result, you need to test fit, measure, and work out the correct engine mounts for your engine, car, and setup. However, if you know that you want to set the engine back an inch or more, you have already guaranteed yourself the need for a custom set of engine mounts and extra work.

Aftermarket LS Engine Mounts

Because engine mounts are only one piece of the engine swap system, you need to select engine mounts that correctly position your engine in the chassis with the oil pan and transmission crossmember, and allow adequate room between the valve covers and the firewall. Fortunately, all LS engines have the mounting bosses in the same location. The following are some of the sources that make high-quality engine mounts.

Dirty Dingo: Dirty Dingo Slider engine mounts provide a wide range of adjustability. According to the company, the mounts move the engine vertically up to 1/4 inch and allow mounting it 2 inches aft while being able to use the factor rubber mounts (in some cases). Double check that these measurements work with your application, so you don't run into problems. You might want to give them a call just in case.

Holley: Holley made a push in 2010 to become one of the major LS aftermarket suppliers for swappers. I had to sit up and take notice at the advances Holley has made in its LS swap lineup. Holley offers a complete line of LS swapping accessories and products. Specifi cally, its catalog of engine mounts can cover nearly every possible swap known to exist. The company offers a mount plate for 1/2 inch forward, 11 ⁄4 inches and 1/2 inch up, stock, and 3 inches forward.

Holley makes a wide range of engine mounts for just about any LS engine project. The company has four sizes ranging from 3 inches forward of the stock location (top) all the way to the stock location (bottom) and everything in between. The zerooffset piece is often used for many F-Body swaps. There are lots of options that allow you to move the engine backward. Rarely does anyone want to move it forward because the front crossmember interferes with the oil pan. For anything greater than a 3-inch movement rearward, you will likely have to fabricate mounts.

Holley also makes mounts for the clamshell-style mount in the stock location. While many swappers do not opt for these mounts, some installers facing unique installation challenges may select them.

ATS: As mentioned previously, I chose a lot of the parts for my vehicle based on a performance aspect. ATS's engine mounts are made from aluminum rather than steel, and thus reduce weight. This weight saving might not seem like much, but when added to many other weight-saving procedures, it can add up to quite a bit. In the racing world, every little ounce is fodder for being chucked overboard.

LSB

Engine Mount Installation