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Unread 06-09-2014, 05:24 PM
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Fair! Fair! is offline
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Default Re: Vorshlag Scion FR-S LSx Alpha Project

Project Updates for June 9, 2014: It has been a hectic couple of months at Vorshlag since my last update. We were buried in early 2014 season preparations and parts sales for many of our customers as well as prepping and racing one of our cars (2011 Mustang in NASA TT3). We also have to pace our V8 swap kit development projects like this one (where Vorshlag writes off about 75% of the hours towards kit development) with paying customer service and race prep work - that pays the bills. I got a little busy myself as well, but after a nasty 150 mph crash I had at Road Atlanta a month ago, that side-lined me from racing for a bit, I'm getting caught up on a lot of project build posts like this one (and this, and that, and even this). During these past two months our shop has made some good headway on this FR-S V8 swap and the NB Miata LS1 Alpha project, which I'm writing an update for next. Let's go ahead and dive into where we are now on the FT86 V8 swap...

Drivetrain Mounting in Kit Form is Tricky

As I've said before, making a one-off V8 swap is relatively easy. Bring us a car, choose the drivetrain, and we can get it in there in a couple of months for a race car (we did just that for a customer in January-February, as well as full race prep, custom brakes, custom cage, all safety gear, and a full re-wire and re-plumb from front to back). One-off V8 swaps go much faster because you can cut things out of the way and just fabricate the best solution in the tie allotted. Making the custom motor and transmission mounts even for a one-off V8 swap is still relatively easy - its takes about a day and a half on something like this FR-S, once you have the drivetrain in the right spot.

Left: Big ugly hole in firewall patched with aluminum, held in place temporarily by Clecos. Right: A big hole was filled with shiny new steel

We could just stuff the drivetrain in there wherever we wanted; cut away the firewall or tunnel or whatever is in the way; measure everything to get the driveline angles perfected, leveled and centered; then cut a hole for the shifter. After that was done we would go back and plate over the holes with aluminum or even patch in sheet steel to make it look OEM, like we did on the firewall for this one-off Ford Coyote 5.0L V8 swap above last week. This was a one-off V8 swap that was brought to us to complete. To fill some holes in the firewall we used two methods: aluminum panels in the left picture and seamlessly integrated welded steel panels on the right, as shown above.

Making these custom panels to cover up holes or other sins is common on a race car, and they can be done on a street car and look seamless and factory, but not easily in kit form. The pictures below were on a car that never had this particular transmission installed by the factory, and it didn't fit the trans tunnel. So part of the tunnel was cut away then a new cover was custom fabricated out of aluminum and bolted in place.

With the finished transmission cover panel bolted in place (with captured "rivnuts" so you don't have to hold a nut on the back side) and later covered in thermal insulating material, it was no longer an unsafe gaping hole in the floorpan. This particular aluminum panel structure can be unbolted to access the tailshaft, add fluid to the shifter opening or replace/re-grease shifter mechanism. It also makes drivetrain removal even easier when removed, yet it is still heat and fireproof. On a street car this could all be under carpet and fully functional.

But for an engine swap that we want others to be able to replicate in their garage using our parts, this type of significant tunnel or firewall surgery and custom fitted panels is not an option. You don't want to have to try to copy where we cut out this piece of sheet metal then make patches to fit, no no no. Yet there are some popular LS1 swaps out there that do expect you to strip your street car down to the bare tub, cut out the transmission tunnel or firewall and just "make it clear the engine where our mounts put it". Significant welding and custom fabrication work is not what we'd call a "do it yourself swap kit"

Our BMW swap kits are made to bolt-in without any welding or fabrication needed, and that's how we're designing or FT86 LSx swap kit - as much as possible. To make a swap kit that is easily repeatable takes a LOT more work involved in the initial design. Our choices of drivetrain parts and locations are narrowed considerably when you cannot cut the tunnel or firewall out and replace pieces or entire sections with new bits. You have seen how many transmissions we've tested on this swap (4). We could have made any of them fit with enough custom fabrication work on the tunnel and firewall, but that's not a "production swap kit", that's a "one-off swap". And we are making a production kit here...

The remote coolant reservoir above, which we make for our BMW E36 chassis LS1 swap, bolts into 3 factory threaded holes in the chassis. It has an integrated mount for the factory heater control valve, relocated from across the engine bay. It houses the factory BMW level sensor on the bottom side, which fits in a channel that happened to be there. The heater hoses clear the routing for our A/C lines. Making new parts fit with all of these constraints takes lots of extra time to plan for and build around. We have to make all of our swap kit components key off of and/or bolt into factory holes. This ensures everyone can locate the drivetrain or other bits we are changing in the same exact spots as we designed. We also go to great lengths to prevent the need for a welder, or cutting off of huge chunks of the chassis, firewall and transmission tunnel.

This extra work required to make everything function as factory looking swap, with proper engineering principles, takes tons of extra time. Time we get to pay for, not the Alpha customers that work with us. They just have to be patient while we go to these extra lengths, on our dime, but our Alpha swap customers have all been great.

The way we make the mounts also has to take into account production manufacturing techniques, like computer CNC Laser Cut portions of sheet or plate steel or aluminum. We even add things like holes, slots and tabs to key or bolt together during fabrication, using our custom production fixtures, to have make each motor mount or transmission crossmember to be as accurate to the original. And fit the chassis as well as as possible. Making a one-off set of mounts would be SO much easier.

FR-S LSx Drivetrain Mounts Version 2.0

The more we looked at the hood clearance, the less we liked the old LS3 intake and throttle body location. It was time for Ver 2.0

We have already made one set of motor mounts for this swap, but after closer examination, I had the guys chunk them in the recycle bin and start over. We had left an extra 1/2 inch that we could move the engine rearward after removing one additional, bolted-on factory part off the firewall. That meant 20+ hours of measuring, mock-up, re-measuring, tweaking and fabrication were thrown away. Moving the engine back as far as possible without cutting the firewall is THAT important, especially when we could make a lot of these FR-S swap kits (we've officially surpassed 100 kits for the LS1 BMW E36 chassis now).

Our crew here was cool with it, just more development hours. Once the engine was moved back to the final, optimum location Olof and Brad noticed one or two factory bits that were really in the way of a better mounting solution. Our new head fabricator Ryan H expressed his concerns over a couple of stamped sheet metal bits that he thought should be removed, so we had a meeting and after a few spot welds were cut, the remaining tunnel structure was much more favorable to the mounts we wanted to build.

As you can see in two pictures I originally posted in my first update, shown again above, the Tremec Magnum XL was getting awfully close to one of the transmission tunnel support brackets. This is a U-shaped stamped sheet metal structure spot welded into the sheet metal tunnel that the OEM transmission mounting bracket supports were then spot welded to (see my original post describing the removal of those). After we moved the drivetrain back that crucial 1/2 inch this U-shaped piece interfered with the Magnum XL. Instead of having our customers just "clearance here" on this structure we decided to simply remove them. And in any case, after we had removed the two little brackets (post #1) this big U-shaped support was no longer needed (it was simply a place to mount other brackets to).

With the U-shaped structure finally removed (about two dozen spot welds) the transmission tunnel had lots of room

continued below

Last edited by Fair!; 06-11-2014 at 05:56 PM.
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