VR6 Fiero - The First Year of the VR6

To say we love the VR6 at Schwa MotorSports would be an understatement. I have an adapter plate to install one in a subaru, the W8 in my Lotus, and the 12v turbo in my rabbit. To say we are picky would be another understatement. As talked about, in my Lotus W8 build, one of the things that makes the VR motors so known and loved is the intake growl when you get some rpms on the motor. Sadly lowering compression hurts that sound, changing the exhaust set up hurts the sound, and of course shortening the runners hurts the sound. So when most people turbo a VR6 they often drop compression, shorten up the intake runners and go to a turbo manifold, even with all of that the motors still sound awesome. We are picky though  and want it all. When it comes to engine swaps people will often tell you cross brand swapping engines is wrong, what more reason do we need? Now we have a love for an engine, people telling us its wrong, a high horsepower potential on a stock engine, a stronger transmission that bolts to the new motor, and best of all the motor and transmission were already on the shelf. Mock up started quickly to see where cutting was needed on the cradle:

At the time the Ttop Fiero was still on the road and being driven, while the 3900 swap 88 Coupe was in the shop for a clutch job so it got used to mock up the install:

Without the intake manifold it fit great, but adding the large long runner manifold on and things changed:

The 24v VR6 used what they called a power port to promote higher rpm horsepower and was controller by a roller in the front of the manifold all of which was taking up too much room. The manifold was taken to the band saw and trimmed a fair amount:

Plenty of clearance was gained and the reality of the project actually working could be seen:

So much room you can even see the alternator from the top:

With the drivetrain fitting in a car attention was turned to making mounts so the motor wouldn't move again. To eliminate the need for an upper dogbone mount, like the original Fiero ran, a four mount system was implemented. A front passenger mount was bolted to the block under the accessory bracket:

The front driver sound mount was attempted to be kept in line with the other front mount but was bolted tot he transmission:

On the rear a mount was built on the block and transmission:

For the belt drive we are doing something a little different for a custom VR6 set up than most. We needed air conditioning but no power steering. Also unlike most VR6 installs that have a subframe in the rear the Fiero's subframe goes around the whole engine. This really isn't a problem, except for the fact of how we are running the belt. To run a factory AC compressor from a GTI, which actually runs on the backside of the belt, an idler pulley would be needed down where the power steering pump used to be, our subframe would interfere with that belt. As an alternative a Touareg accessory mount was found and fitted which adds an idler pulley above the AC compressor and moved the alternator out slightly, this almost solved all the problems. The last issue to overcome was the Touareg AC compressor, sadly it was a fully variable displacement compressor that didn't use a clutch, the AC would work all the time. Our track record with ac on a car that hasn't had it for years is the system will leak down a few times before all the leaks are fixed, if that was to happen with the Touareg compressor it would potentially seize and possibly throw the belt. Add that to the fact that the compressor would need some form of logic to control the displacement which we also didn't have. In proper Schwa MotorSports fashion a GM AC compressor was fitted to the accessories bracket with a few custom mounts and the belt routing was ready for a proper fitting belt:

One of the big issues with adapting non-native drivetrains, and even more of a problem when the placement of the drivetrain changes (front engine to mid engine) is making sure you can shift gear. The Fiero used a cable shift set up just like the GTI, but the GTI required the opposite motion for the select cable and when you couple that with the fact that the Fiero's shifter is far from spectacular and the VW floating ball shifter is amazing the choice to adapt the VW shifter was obvious. The first step was to adapt the cables at the transmission end. Wanting the best shifting Fiero a billet short shift kit was purchased to clean up slop and enhance the feel:

The shifter assembly was modified fairly easily with just holes put in the back to allows the cables to exit the rear instead of the front and small brackets were made to mount the larger VW shifter to the factory Fiero studs in the tunnel:

The VW cables weren't quite long enough though, with the given space and a welder in hand extension rods were added to the shifter side of the cables and the rods were bent to clear the tunnel and angle into the box. A small bracket was made utilizing existing bolts to hold the cables in place under the arm rest:

After plenty of tweaking and adjusting the bracket on the transmission was trimmed and supported:

A quick run through the gears and it was the first glimpse into how much improvement this shifter was going to provide:

A more and more common theme on modern drivetrains is to use the same end of a transverse motor for both coolant fitting going to the radiator. Since the Fiero relays on a metal tube on each side of the car to get the coolant to and from the front mounted radiator this forces the use of fairly long coolant lines with a number of bends to clear everything:

Since you can't take out a turbocharged 3.4l engine and replace it with a 220hp 2.8l engine a turbocharger was needed to make up the power difference. A billet 64mm Turbonetics turbo that was put on the shelf year ago was brought back into action. This turbo was on the VR6 Turbo rabbit for a short period of time before being removed for a smaller unit due to the fact that it was too quiet on a small displacement low boost engine. To help with that and to stretch ourselves a little some research was done on a modification to the compressor housing to add an anti-surge duct to the housing that helps the turbo make a little more noise. This is a bit of a scary process, you have to machine a large portion out of the compressor housing and then machine an inset to be installed in place of the missing material. You basically take a hard to find compressor housing and mill it down:

The insert was then machined itself, through a mix of our CNC mill and the lathe:

This piece is then inserted into the compressor housing to create the anti-surge duct that makes all the noise:

Take all of that and bolt it to a cast turbo manifold and it fits nice and to the block and eleven allows for the factory heat shield to stay fitted:

Unfortunately our ECU of choice, Microsquirt, can't handle controlling some smart ignition coils directly, mostly just VW/Audi coils. Instead a GM ignition coil that we had been used on a few swaps already had been working amazingly and was quickly fitted and plug wires were built and routed:

Lucky for us the plug wires tucked under the stock manifold and went right into the spark plug wells without issue:

At this point all the mock up was done, the valve cover was trimmed for the truck to be able to shut fully and it was down to the back stretch. The turbo GM v6 setup that was in the car was sold to a local member installed into their Formula, space was cleared out the Ttop was drove into the shop along with their Formula and out came the old heart:

For the first time the Turbo VR6 was going into its home:

Not without problems though, since we can't seam to leave things alone and fully expect some changes to be made to this car, so as mentioned earlier a cast turbo manifold was used, this was a quality product and it kept the install simple, but it didn't quite fit and the grinder came out and was taken to the trunk for a very small notch:

With that done the motor was in for the first time:

An extension pipe was made to adapt to a cadillac northstar throttle body as well as get the larger cable driven throttle body away from the trunk wall. Final welding was done to the intake tube and the valve cover and installed back onto the motor:

The motor was pulled back out to beginning wiring and we got the intake back from the painter who bonded the runners back together after we cut the large holes in them: 

Looking good:

But looking good was all it did. This began a downward spiral that was longer than we would have hoped for. The first start up was sad, at this point we have built so many cars with computers we have wired we are very familiar with not starting the first time, or the second time, or so many times later that we kill a starter before finding the last little issue. But this was different, it would start and run, but never run good, this was a mid engine VR6 Fiero with little to no exhaust, it should sound amazing! It should rev quick and aggressively, it didn't, it would sputter up to almost and idle and struggle to stay there. Lucky for us we know a lot of people, and one of them happened to be a pro with the VR6 and he quickly pointed out a firing order issue. A quick check to confirm the VR6 firing order: 1-5-3-6-2-4 with the 3 paired ignition coils being 1-3, 2-5, 3-4. A quick check to see the firing order of the donor motor for the ignition coil: 1-2-3-4-5-6 with the 3 paired ignition coils being 1-4, 2-5, 3-6. Pretty close but 3 and 4 are flipped and in our haste of the install we built the wires to the numbers on the coil and not the firing order of the motor. Quick flip of the wires and it was running.

Sadly we weren't quite quick enough on fixing the problem though. The intake is ABS plastic, and the holes in the manifold were filled with steel plates and panel bond before being painted, before test running the intake was tested to 10psi with shop air and held beautifully. But a misfiring engine with flipped plug wires does two things, it fires one cylinder early and one cylinder late. That early firing cylinder happened to fire with the intake valve open and caused a nice intake backfire, while most cars can handle this, the panel bond couldn't, the 10psi pressure test isn't quite the same as a backfire, and the intake blew up, throwing a piece of the intake off into the abyss of the engine bay.

With the firing order fixed and the car getting tuned in we were almost out of the water. The motor wasn't very smooth and while driving you could feel random drops of power, not quite enough to see in the wideband but you could feel it. To top it off during cranking the motor would give a nice intake backfire, and as you might have guessed blew up the intake a few more time. Not sure what to do a set of injectors was found locally for testing. The injectors that were installed in the car were Deka 80lbs injector and supposed to be legitimate injectors but sadly we were dooped. The Deutschwerks 60lbs injectors installed and the fueling tables actually needed reduced even though the injectors were smaller. The car was finally driving, and driving right:

Just like the 3400 swap, a few months after install with less than preferred test miles on the car the Ttop again lead the pack of Fiero's down to Eureka Springs for the annual club trip:

But unlike years past we were the only car to have problems. Since the wide body had been on the road we had never finished up the wheel wells, and until the trip to Eureka this wasn't a problem. Towards the end of the drive the rain finally got bad enough that the air filter in the wheel well started to plug up with water and choke out the motor. With a few more days of driving ahead of us and more rain in the forcast a solution was needed. Being in small town with limited options a plastic yard "For Sale" sign was found at a hardware store and quickly trimmed down to guard the filter from the water off the tire. The weather didn't let us down either, the next morning our drive to lunch was a mix of heavy fog and rain, and the Ttop performed flawlessly.

The Ttop Lead the pack through the Arkansas mountains and on Arkansas's own Tail of the Dragon and completed the trip back home without any more problems.

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