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Unread 04-12-2014, 02:35 PM
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Fair! Fair! is offline
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Default Re: Vorshlag Scion FR-S LSx Alpha Project

continued from above

Alpha FR-S LSx Swap Outline

What we have planned is simple and meshes with the customer's needs and the shop that brought him to us. I will give the basics here, and show the step-by-step fabrication and development pictures as the V8 swap kit is developed. We won't give away EVERY detail, as we've had copycats try to duplicate our work over the years. So I won't give away part numbers, finite measurements and the like, but we will show more than enough to let you readers see how we do a new Alpha build.

The owner of this car is named Rick and he found his was to Texas Track Works in late 2013, a shop in Ft Worth the specializes in track prep, race alignments and more - and is a Vorshlag camber plate dealer. Even though in some ways we are competitors we are we are friends with the staff at Texas Track Works and will partner with them to complete this Alpha build. They are the reason why we have the opportunity to work on this particular FR-S, and for that we are thankful. Rick rode in one of TTW's customer's track/street cars: a Nissan 240SX (above left) with a LS1 swap installed by TTW. We've raced against this car in NASA TT3 in our TT3 Mustang (above right) and that Nissan really scoots. This Nissan is a clean install - unlike some of the hack V8 swaps we've seen built elsewhere, the TTW crew gets the details right and has the race experience to know what matters. After that test ride in that lightweight RWD coupe with proper LSx V8 power, Rick knew what he wanted in his FR-S... LSx V8 power! After that decision it didn't take Texas Track Works long to make the call to us here at Vorshlag, and we came to an agreement: where Vorshlag would cover the development costs of this swap if we could see a way to make it as a kit. So they brought us the car in early January 2014 and we took a look...

Once the OEM drivetrain and turbo kit were removed we got a closer look at the naked the engine bay. Wow, the underhood area is HUGE! The frame rails are a staggering 31" to 33" wide (they taper in at the back), to house the immense Subaru flat-4 cylinder engine, and I felt immediately that the LSx swap would fit well. We first took a LS1/T56 mock-up drivetrain we keep on hand for swap development and tried to stuff it into the car...

Our first LSx V8 + Tremec T56 mock-up had the shifter portion was way too far forward, but we knew what to do.

Hmm, the traditional 1998-2002 Camaro/Firebird Tremec T56 6-spd was too short, as was the next drivetrain we tried: an LS1 with a Tremec TKO600 5-spd. That transmission length was even worse, and no matter how far back we moved the engine the shifter location was still way forward of the factory shift boot and opening in the center console. The TKO600's shifter was way inside where the dash would be. Neither would work.

These two secondary braces had to be removed, and after using our spot weld cutter on 6 spot welds each one fell right out

After removing one spot-welded transmission tunnel brace (see above) and unbolting a few items mounted to the firewall, we did some more drivetrain mock-ups and got the engine back as far as we could without serious tunnel surgery, something we always try to avoid in any swap we want a customer to be able to replicate in their home garage. We measured the shifter location on a ZF S6-40 6-spd transmission we also had on hand, and it wasn't anywhere close either. We finally called our transmission expert, Joe D, and he mentioned the Tremec Magnum XL 6-spd that featured a direct mounted shifter about 5.5" further back than the normal direct-shift T56.

The second drivetrain we swapped in was another LSx V8 and a Tremec TKO600 5-spd

This transmission was developed for the S197 5.0 Mustang chassis as well as the 5th gen Camaro LS3, but never came from the factory installed in either car. Both of these cars come with factory transmissions that have remote mounted shifters, and in both cases the shift feel is terrible. We've installed T56 Magnum XL 6-speeds into late model Mustangs and the difference in shift feel is remarkable, not to mention the extra torque capacity these have (rated at 700 ft-lbs of torque!) compared to the stock Gretrag MT-82 in the 5.0 Mustang.

The long-awaited and custom ordered Tremec T56 Magnum XL arrived!

The problem was, Tremec hadn't yet made the production model of the transmission to work with the GM LS-series engines. Joe said he could custom build us one with an input shaft made to fit the flywheel depth and pilot hole diameter of the LSx, like he has done for Grand Am and World Challenge racers with 5th gen Camaros. So after many measurements and inspections on the FR-S engine bay and tunnel we took a gamble, ordered this custom Magnum XL transmission and waited for it to arrive. We also picked up an LS2 GTO 6.0L oil pan, which has a "front sump", hoping it would clear the FR-S crossmember. Based on previous swaps and where this FR-S crossmember was located, I felt this "front sump" oil pan would fit.

The final LSx + T56 Magnum XL drivetrain placement was about as perfect as you can get

After many weeks of waiting the Magnum XL arrived and we got to work on the final series of drivetrain mock-ups. We also bought a new LS3 intake manifold kit, complete with fuel rail and drive-by-wire LS3 throttle body. We want to use the later model Corvette LS3 PCM (power control module), as it has a faster processor and advanced CAN-BUS options, to better match the FR-S systems. That means we would use the LS3 intake manifold, which has an electronically controlled throttle and not a direct cable controlled throttle. The cylinder heads for the LS3 are different than what we have on our mock-up block, but at this step it didn't matter.

After about 6 or 7 iterations and tweaks with the "LS3" + Magnum XL drivetrain in and out of the car we finally have the engine where we want it, as far back as the heater core and intake allow. We then tweaked the driveline angle (downward tilt of the engine) to match the factory diff angle. Then we started building the prototype set of motor mounts.

That's where we are now, and today our crew removed the interior to help develop the transmission crossmember. After those bits are done we will develop a full length 1-3/4" primary stainless steel header with 3" collectors. Unlike what some other V8 swap kit makers like to do, we make real exhaust headers the hard way, because it makes SO much more power everywhere. The shortcut normally taken by others it so buy a cheap set of 1-1/2" "block hugger" shorty universal fit headers, heat them with a torch and smash any tube with a hammer that gets in the way.

The BMW E46 LSx prototype headers were developed and built in house, with final production by a major US header manufacturer

That short cut header is a huge restriction and can cost upwards of 50 hp, but making custom full length headers is so much work that most shops won't bother. We wouldn't have it any other way, and our production full length headers tend to add 40 hp over stock. Once the prototype headers are made here at Vorshlag we will ship them to our production header supplier, where they will make fixtures based on our prototype set. Then they will make a production run of stainless steel headers using a CNC bender, making our kit headers both more cost effective and improving fit repeatability.

And yes, for you California folks we have tested many sets of OEM exhaust manifolds and found one that fits, so this swap could feasibly meet 50 state emissions and pass the CARB referees, but we won't likely do one of those for a while. Our installs will all have our headers, and if its a street car we will add proper catalysts as well.

Vorshlag production 1-3/4" x 3" full length stainless steel headers fit the E36 BMW chassis like a glove

Everything else will be built in-house, like our production E36 and E46 motor mounts are now. We use CNC laser cut flanges, bolt them into our production fixtures, then TIG-weld everything together. Each welded part is testing on another fixture, then they are powder coated for long term durability and good looks.

After the drivetrain mounts and headers are built there are still a dozen of other parts and sub-systems to tackle, but its nothing we haven't done many times before: Cooling system hoses, reservoirs, radiator and fans; intake air tubing, filters, and MAF sensor; electrical wiring to the engine, gauges, OBD-II port and CAN-BUS integration; driveshaft, shifter and transmission crossmember fabrication; fuel pump, lines, hoses and regulator, from the tank to the engine; and last would be the relocation of various components that were in the way of the V8. There could be more than that, but so far that is a valid list.

What About the Weight???

The number one question we get on every build is "how much weight will the V8 add?" Don't worry... we know Newton's Second Law of Motion: F = ma. We're going to really up the "a" with the LS engine and keep the "m" as low as possible.

We here at Vorshlag are fanatics about weight, even when we are racing in our 3800 pound TT3 Mustang, heh. We weigh everything during a build like this, and we have already weighed lots of FT86 bits in the BRZ project build thread. You will see lots of pictures with various bits on one of our digital scales in this thread also. Why? Because the internet is full of poor data, numbers that turn out to be bogus, and people that are full of crap. We bring the tech, and when it comes to weights we show pictures of anything we reference on a proper scale.

Here's an example of a race-prepped BMW 3 series with LS1 V8 power at 2508 pounds. That's with a full road race legal roll cage, too!

Often times, as with our BMW LS1 swaps, the additional weight of the all-aluminum and compact LSx series of V8s is nil, and we only gain weight in the transmission (the T56 6-speed is a brute and weighs over 125 pounds). Our full street duty/full interior BMW swaps are usually within 20-40 pounds of the stock set-up. The iron block inline-6 engines used in E36 3 series BMWs is HEAVY and long, and the LS1 engine is a hair lighter and about 12 inches shorter, which moves the drivetrain mass rearward for better front:rear weight bias. We feel that the FR-S LSx is going to be much along the same lines, with more rearward weight bias and a gain of 40-50 pounds, at most. This isn't some wild guess, but based on dozens of previous swaps, and weights we've taken of these engines before.

Remember the 480 pound measurement of the factory FA20 and 5-spd, shown above? Well a Tremec T56 Magnum XL is 128 pounds and a factory LS6 weighs 457 pounds, with a lighter than stock flywheel (which we always do - it doesn't need a 48 pound 2-piece factory flywheel, even for street use) plus the heavy OEM exhaust manifolds and a power steering pump. This 86 chassis has electric assist power steering built in the steering column, so we will remove the hydraulic power steering pump from the LSx engine we end up with, and our exhaust headers always save weight over OEM cast iron manifolds. After we do the math it looks like it is going to be pretty close to the stock weight, which is good. The weight of a turbocharger and intercooler from our before weight here is not insignificant, either. If we're wrong on that guess, we'll show it here, too. Look for the final weight of the FR-S once this V8 swap is done, which we will compare with the "before" weight.

What's Next?

That's enough for now. Tune in next time when we have the motor mounts completed and start to tackle the next bits like the driveshaft, headers, fuel system changes, and wiring. And yes, we have an OBD2 expert already on the case to make the GM computer talk to the factory FT86 computer, and our build here will have functional gauges and electric power steering.

Please note: ANY NEWS about the swap kit, swap parts availability and pricing will be posted here AS SOON AS WE HAVE IT. Please don't call our over-taxed employees at Vorshlag or the folks at Texas Track Works to ask "when will the kits be released??" - we will post any news here first.


Last edited by Fair!; 04-12-2014 at 02:40 PM.
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