Vorshlag BRZ Project Build Thread (aka: the Miata Coupe?!)

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Mark said the rear studs were easy to install once he figured out how to remove the rear hub assembly (see above left). Off comes the half shaft retaining nut, then you unbolt the hub assembly from the emergency brake bits and you can remove the rear hub. Once removed from the car, you can use a press to push out the rear studs; the new studs go in the same way. With the Vorshlag 65mm studs installed out back, now there is full engagement of the threads on the longer/larger Vorshlag lug nuts even with that 10mm spacer installed (see above, right).



Our 65mm Subaru style Vorshlag wheel studs install into either the front or rear hubs relatively easily. As you can see the installed length is 48mm past the hub face up front, compared to only 25mm of stud protruding with the stock wheel studs. This upgrade gives you a solid 23 mm increase in stud length over stock, but they don't look silly or stick out excessively with the Vorshlag lug nuts. A solid upgrade for any track or autocross car - more lug nut engagement and the ability to run up to a 20mm thick spacer, if needed.



We installed these on the front hubs of Matt's BRZ when he upgraded to 255/40/17 Hankook R-S3 tires. The front wheels needed a 5mm spacer to allow this fat tire to clear the struts. Any spacer use requires longer wheel studs, as the stock studs are very short. This also necessitates new lug nuts since the stock nuts are very short, close ended lug nuts.



For those extra picky folks worried about long wheel studs making their FT86 look like Roman chariot wheel spikes, or the modern equivalent, fear not. As you can see above on the BRZ with our "65mm wheels studs" and a 5mm spacer there isn't a hideous amount of stud protruding past the lug nuts. This is just how a race tech inspector wants to see - full lug nut engagement, plus a little more. Perfect.

GRM Photoshoot

We got a call from someone that writes for Grassroots Motorsports asking for a pictures of an FT86. They were looking for some action shots with typical autocross classing/sponsor stickers shown mid-corner or in a slalom. They had a tight deadline and nobody had any pictures of an STX prepped FR-S or BRZ they could find. We love working with magazines and especially the folks at GRM, so we made it happen.



Olof washed and detailed Matt's car, Jason cut some class/number/sponsor decals, and Olof and I slapped on the numbers and some GRM decals. I asked Jason to make the numbers big, but dang - you can see these from space! :P Then we went in search for a parking lot that would work for the photo shoot. Once there, we set up a slalom and Brandon got his camera gear ready. I got in, strapped on a helmet, and hooned around the cones - while keeping an eye out for the law. This was an unsanctioned operation...

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The parking lot we picked was a local movie theater across the highway from Vorshlag, and by a large helping of dumb luck we just happened to see my 2013 Mustang GT parked in the same portion of the giant parking lot. Apparently my wife had snuck off to watch some sparkly vampire movie - on a vacation day she took from work that she "needed" in order to get ready for a Thanksgiving party we were throwing the next day. Sneaky. What she didn't know was that I had an extra key to this car... so we moved it to another lot about a half mile away and I waited for her panicked call. :)



It didn't take long - half an hour later I got the call, "The Mustang is stolen! Either that... or.... YOU took it!" She knows me too well. I told her where the car was parked and she hung up on me. Later that day she admitted it was a good practical joke, heh. We laughed about it for days!

The photos came out well and you should see one of the above shots in an upcoming GRM issue.

Two FT86 Track Tests @ ECR

At the end of my October post we had three track days in the works for October and November. Matt was out of town for the NASA event, where we ran two of the other Vorshlag shop cars and set some new personal best lap times (in our 2011 and and 2013 Mustang GTs). Then the SCCA Club Race/PDX event was cancelled (they had all of 37 people sign up...and we were 3 of those. Club racing in our region is virtually dead), but the Five Star Ford track day event was the first one where we had some FT86 content.

Vorshlag Picture Gallery - 5 Star Ford ECR Track Day - http://vorshlag.smugmug.com/Racing-E...ar-ECR-111712/

This November 17th event was an HPDE hosted by Five Star Ford of Plano at Eagles Canyon Raceway. We had fun at their event back in June so we signed up three more cars for their November 17th event. Amy drove the red Vorshlag 2011 Mustang GT to her new personal best at this track (1:57.70!) and Matt drove his 2013 Subaru BRZ (2:11.0). I was there for track-side help and in-car instruction, Ed was there to help with the three cars, and Vorshlag's photographer Brandon was on hand and took some great track pictures of many of the cars in attendance. Perfect weather, well run event, and we had about 63 cars in attendance, so we got a LOT of track time. Big thanks to Corey White for setting this event up!


Left: Matt's BRZ on course. Right: Britney and her FR-S.

Being a Ford dealership sponsored event there were a crap ton of Mustangs in attendance, and I will go into more of that in our next Mustang project thread post. Having two FT86s there was a treat - and in fact there was a third one, but it was still on the stock tires and had no lap timer (we ended up doing track preparation work to that car at Vorshlag in December).



Britney and Stephen also brought her FR-S to this event, and you can see me riding along with Stephen in the Asphalt Gray FR-S, below right. NASA Time Trial racer KenO took some hot laps in her FR-S during a later session, and I took some hot laps in Matt's BRZ at the same time (below left). We both had lap timers/data loggers on board, but unfortunately we didn't get any in-car video in either car that day. Still, we did get some good pictures and data.



The data showed what we felt in the BRZ - the new brake pads were working VERY WELL and I saw some braking data that I couldn't quite believe (1.5g peak braking?!). The harder I pushed the brakes, the deeper it would brake. This was just with Motul fluid, our SS brake lines and the Carbotech XP12 front / XP8 rear pads! No brake ducting, but we never saw any fade - and I pushed the brakes hard for about 4-5 laps. Lateral grip was also extremely impressive, showing sections of corners with sustained 1.3-1.4g lateral?!



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Again, I have to see more data to believe this, but the fat R-S3's were making mountains of grip. Like I said before, the track width on these 17x9" wheels is 71", which is WIDE. By comparison our Mustang, which is a giant 3600 pound car, on the mega-wide 18x12" wheels is 73.5" wide - a mere 2.5" wider than the 2750 pound BRZ. So you can see where some of the massive grip is coming from on the FT86. This chassis has a "wide stance" and as we know, track width adds lateral grip. The OEM shocks were a bit floaty in bumpy sections of the track, and it bottomed the fronts a few times a lap, so it will be much better with real monotube dampers. In a handful of laps with Matt riding along, I managed a 2:10.5 lap in heavy traffic, after seeing a 2:09.5 indicated on this same lap. So given a few more laps and no passenger it is a 2:08-2:09 car at ECR as it sits, which ain't half bad. I was making Matt nervous sliding the car around, but he hopped in for the second half of this session and dropped two seconds following the same lines, and pushing the braking points deeper like I had, to manage his 2:11.0 lap.


Left: We set-up a table showing off some Vorshlag and Whiteline parts. Right: Vorshlag/AST tester KenO in his E46 M3.

KenO took the 215mm R-S3 equipped FR-S to a best lap of 2:11.5, which was quite good considering it had Hawk HPS pads and only 7" wide wheels. We both had passengers on our laps, and in a 2750 pound car an extra 150-200 pounds matters. I hope we can get these FT86 twins back out to ECR soon and really open them up. I haven't had this much fun tracking a sub-200 whp car... EVER. :)

Yes, I will admit that driving the BRZ on track with these minor mods was a lot of fun. And I'm a bit of a snob when it comes to track cars, normally driving something with nearly three times this power level, which says a lot about the "fun factor" of the FT86. The car did everything so well - turning, stopping, shifting, corner exit. The pedals are placed perfectly for heel-toe down shifting, the brake and steering feel is superb, the shift throw is short, and the stock seats mostly keep you in place on sticky street tires. Sure, a proper harness and race seat would help driver confidence considerably, but it was a great overall package with just the added negative camber, fat and sticky street tires, and good brake pads/fluid/lines. The prototype Swift springs were a bit on the soft side, and we're about to swap in the production units next, along with shortened bump stops. That should keep the front suspension from bottoming on the bumpy bits at ECR and should help drop lap times too. We'll be back!

Vorshlag picture gallery for ECR Toy Run - http://vorshlag.smugmug.com/Racing-E...un-ECR-120812/

We were back at ECR once again a few weeks later, on December 8th, and Matt again brought his BRZ with zero changes from the November event. It was a much colder day and lap times were a solid 1-1.5 seconds off our times at the Ford event, when the weather was a bit more favorable. This time Matt took a lot more laps and got more acquainted with his car. I was busy driving my 2013 GT with new AST double adjustable shocks and Vorshlag camber plates, and Amy was in her 2011 GT again. Also, two of my buddies and I were doing our first track laps in our future ChumpCar, so it was a very busy day. It was so busy, in fact, that nobody got any pictures of Matt's BRZ on track! Doh. It looked so purdy with all of the decals... oh well.



He did get a little in-car video with his new GoPro Hero3. Not the best audio, but you can get some idea of what this car looks like on track.



For NASA TTD competition (the NASA class we are building it for), it needs to run closer to a 2:05, but with coilovers and some other tweaks we think that is doable on these R-S3's. For SCCA we're building it around STX class, which allows up to a 265mm tires. I don't think that will fit as it sits, but with their poorly written rules concerning fender contours and lip rolling, "anything is possible". :)

What's Next?

Coilovers are the next obvious modification, but we don't have anything to install yet - still waiting on his AST 4150's. For now we will go ahead and install the production Swift lowering springs and confirm the data we have seen on Mark's car (1" drop, great ride). There are some additional Whiteline FT86 bushings that have made it to market (rear UCA bushings) and more are promised in late January - as are their adjustable FT86 sway bars. No power mods will be done until there is a proper tuning solution, so 167 whp is where it will stay for a while.

We don't have any autocross or track events until February, but if we get in some parts before then we'll post up again. Sorry for the long update today, bu we had almost three months to cover. I will try to be more prompt in my updates in the future.

Cheers,

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Project Update for August 20, 2013: It looks like we had a huge delay since our last project build thread update on the BRZ Project; it hasn't been discussed since December of 2012. There were some lengthy delays waiting on shocks that were a bit out of our control, which we will explain below. We also got very busy with other projects and racing in other cars. But in the past few months a lot has happened behind the scenes with our in-house 2013 BRZ and we've finally installed proper monotube adjustable coilovers that actually fit these cars at lowered ride heights. We put these to good use at an autocross recently with surprisingly good results. Read more below...


What a difference a year makes! Left is bone stock, right is last week on MCS TT1 shocks, 17x9" Enkei RPF1's and 255 BFG Rivals.

One more thing. Starting in early 2013, all of the pictures in my forum posts can be clicked for higher resolution versions, unless they are posted in-line with BIG format pictures. This takes more time and makes the character count of my posts longer, but we feel it is worth the extra effort to split up posts into multiple sections. With a professional photographer on staff, we WANT you to see our images in higher detail. As always, these watermarked pictures are all copyrighted by Vorshlag, so we ask other shops NOT to steal them (yes, it happens). Anyway, if you see something you like, click that pic!

Where Were We? Waiting On Coilovers...

At the end of my last post (What's Next?) in December we had mapped out future suspension mods. Coilovers were the obvious next modification slated, but that didn't quite pan out as we had expected. There were some early coilover shock options for the FT86, most of which were straight off of the Subaru Impreza that this FT86 chassis was loosely based on. But as we saw, many of those early kits were compromised in some way - namely in the fact that the front struts were not utilizing the room under the spindle for extra travel. Unlike the AWD Impreza, the RWD-only FT86 has several extra inches that could be exploited up front for more strut travel, using the area that the AWD Impreza front half shafts would have been. None of the rushed-to-market coilover solutions used that room. The rest of the kits we saw were all twin tube shocks, which we are not fans of.


This picture was made for a photo shoot last year with stock shocks/springs/sway bars. Handling was pretty awful.

Without proper coilovers to install we weren't about to try to autocross or track this car seriously, either. Sure, the production Swift lowering springs arrived and they looked good, but with the stock length struts and shocks there just wasn't a ton of compression travel to be had. And no lowering spring is going to be significantly stiffer than the OEM bits, not enough to matter for performance handling. Sorry, that's just the truth. Lowering springs are 90% for looks and 10% help handling by lowering the CG. When we see folks arguing one brand of lowering spring over another regarding performance, or one model of OEM spring vs another (BRZ vs FR-S), we have to bite our tongues... because we know it is completely pointless internet talk.

Real coilovers geared towards competition use can work with substantial increases in spring rates. Not 0-30% stiffer, like most lowering springs add, but 100-500% stiffer spring rates. Spring rate changes like this cuts way down on chassis roll/heave/dive, and that's where we've seen the biggest gains over the years with suspension changes - spring rate. And no, the spring rates I'm talking about do no automatically mean "bone crushing ride", not if used with proper monotube shocks. The relatively massive pistons in monotube shocks (relative to twin tube shocks, like the OEM bits) make for a massive increase in low speed sensitivity to movement, so they react more quickly to bumps than any twin tube shock ever could, no matter how stiffly valved. And the large range of adjustment in most aftermarket monotube adjustable shocks means they can work with much stiffer rates and still provide a good ride when the valving (knob) is turned down for street use. These reasons are why Vorshlag ONLY sells monotube shocks - we've seen the glaring limitations of twin tube shocks and just don't want to be a part of that "solution". Sure, Twin Tubes shocks are cheap to make and they have their share of budget-oriented fans, but they don't belong on a car that will be used in competition, and are never going to be something we recommend or sell. Yes, some folks call us shock snobs - but we have our reasons.



Nearly 8 months after we ordered the first prototypes we finally got a set of coilovers from a monotube company to test. We tested their set-up on Matt's BRZ several times over 2 days, with and without springs, and we found several issues. These included brackets that didn't fit the mating hoses, mounting holes drilled the wrong sizes, and strut and shock lengths that were completely wrong. There was no easy fix for the strut length problems, either, other than running them at stock ride heights - which we weren't about to settle for. These tests were a real set-back and we knew this would turn into another huge delay. Still, we had hope, so we spec'd out the proper front strut and rear shock lengths and waited to hear back about a new set that could actually work at a lower ride height.

More months of waiting turned up nothing. It was a problem with the supplier, who was unwilling to make any changes - even if every issue we noted was true. Nobody involved came out ahead on this one. We wasted months waiting for a fix that never came and lost a lot of time in the FT86 suspension market. Matt's BRZ was just tooling around on nice wheels, good bushings, and lowering springs - all dressed up but not race worthy. After seeing how this car fared on track with the stock shocks and soft springs, we knew it would be better suited to proper coilover spring rates and dampers, and really wanted to move to the next step.

I cannot fully put my frustration into words, but I'm not throwing any names around. I'm just going to leave it at that. So after we ran out of patience waiting we broke down and looked at other vendors making quality monotube coilovers for the FT86.

Monotube Coilover Solution Found in the MCS TT1

A relatively new shock company we've been eyeing for a while was Motion Control Suspension (aka "MCS"). This is an American company started in 2011 that has the same principles that formerly ran Moton for 12 years. We had seen that they had made their new MCS non-reservoir single adjustable monotube coilovers for the FR-S/BRZ and the SCCA C Stock guys seemed to love them. This run of FT86 coilovers were made explicitly for this class's unusual shock rules: where OEM spring must be used and the shock length can be no more than 1" different from stock.


Left: Moton 2-Way Dampers we built for SCCA Stock Class BMW 135i. Right: Custom perches for F Stock use on S197 Mustang

The MCS solution for this class was sold with adapters to convert them from adjustable height coilovers normally holding 60mm springs over to fixed height struts that worked with the OEM springs. As crazy as that sounds, we have built shocks like this with other shock companies in the past. It is a very small, niche market of a few dozen racers a year that buy shocks for SCCA Stock class. They can easily cost upwards of five thousand of dollars for custom built double adjustable, remote reservoir shocks that work within the narrow confines of the SCCA Stock classes, and they do find performance benefits in a few loopholes... but nothing like a set of proper coilover springs would give them if they weren't saddled with that class' oddball shock/spring rules.

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We loved the quality and durability we've seen in Motons, and I run Moton Doubles with remotes on my personal NASA-TT3 Mustang. But while Moton never offered a single adjustable shock, the folks at MCS did, releasing their non-remote single adjustables in early 2013. A Single adjustable non-remote reservoir monotube coilover is one of the areas we at Vorshlag really excel in. This type of shock has a big chunk of the performance benefits of a 2 or 3-way remote reservoir monotube (that can costs $4500-8000+) but at about half the cost of "remote doubles", and without the hassles of mounting reservoirs/hoses. Monotube Singles are a great solution for 80% of the coilover users out there, and we really needed this "internal single monotube" coilover if we were going to play in the FT86 market.



Since stock springs and stock length struts and shocks aren't what 99% of the FT86 crowd wants, we saw a glimmer of hope in MCS, and wanted to give them a try. We talked to MCS, set-up Vorshlag as a dealer, and ordered one of these FT86 sets in our initial stocking order. We knew they might not be the right length but were willing to test them and see, and they said they'd be willing to customize them to our specs.


Left: MCS TT1 singles for FT86, kit priced as shown is $2750. Right: Vorshlag pinned spanner fits the ride height perches perfectly.

We got our first FT86 set in and they looked absolutely beautiful. We could see they already had a lot problems we saw in other brands solved. The included strut bracketry was made to fit the hoses and lines on the BRZ perfectly. They had a nice solution for the slotted holes found in many struts using precision CNC machined fixed offset insert slugs. The coilover perches were all metal (not plastic) and 2-piece, that clamped in place with spanner wrenches (not bolted) and one of the Vorshlag pinned spanners we've made for other brands of coilovers fit perfectly.


Testing the strut and shock lengths on the first set of MCS singles - almost there...

Sure enough, as the MCS folks expected, their "C Stock" length singles were too long to work at the lowered ride heights we wanted to run this BRZ at. And they should have been, as they were initially intended to be SCCA Stock class legal (it is nearly impossible to make anything legal for Stock class work at properly lowered ride heights - without some major compromise somewhere). You see, we had been looking at NASA Time Trial and SCCA STX to run in, and in those classes we could lower the ride height and use true coilover springs in any rate we wanted - a novel idea that almost any competitor would want.



That day we went through the same battery of measurement exercises with the MCS singles as we always do on any new set of shocks we test. We re-spec'ed them with our desired ride heights, then measuring bump and droop travel at the wheels, with and without springs installed. We sent along our wish list of drawings and measurements and shipped this first set of coilover shocks back to MCS, hoping they would make us a set of housings, shafts and lengths that would work.

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Lo and behold, they delivered a new set built to our specs in less than 2 weeks. We were floored, as this turn-around time was much quicker than we had even hoped for. We took the 2nd set and tested these on the BRZ again, going through our full sweep of tests with and without springs once again. By now we had burned about 4 days of shock testing on this poor car over the previous few months and hadn't driven one mile on anything but the stock shocks. Luckily the third time was a charm, and the 2nd MCS set was a winner. They fit with the lowered ride heights we wanted and now offered real usable bump and rebound travel at both ends. Hot damn!


Left: New Vorshlag tender spring. Right: The MCS TT1 shock worked with the stock rear top mount, Hyperco spring & our tender.

This may seem like a trivial thing to some of your readers, but getting these MCS "TT1" shocks built correctly and onto this car, with real spring rates and usable travel in both bump and rebound directions, was a long time coming. Big thanks to Lex and the folks at MCS for getting these re-made so quickly and for working with us and our needs. So now we needed to know - how do these dampers RIDE and HANDLE?

The ride aspect was easy - let's go drive it. With the initial set of springs we went with a 450 #/in spring at both ends. If you look at the charts below of the OEM and lowering spring rates, which we measured here at Vorshlag, you will see that we nearly tripled the front rates and doubled the rear rates. That's usually a good starting point for us, and we also based the 450F/450R rates on our years of Subaru GD chassis shock sales, testing and racing. To keep the rear spring seated at full droop we added our new Vorshlag 60mm ID tender springs (shown above) on the rear shocks, too.


Left: Stock 2013 Subaru BRZ spring rates, front and rear. Middle: Stock 2013 FR-S rates. Right: Swift BRZ progressive rate lowering springs

A few drives on our 2 mile "shock test loop", a couple of rebound knob changes, and we had the ride set to "Amazing". Yes, with triple the front spring rate it was handling bumps better than the stock shocks did with lowering springs, which often bottomed out. It was firmer but not at all jarring, and we quickly knew this would be a big seller.

Note: We have renamed MCS' line of shocks with actual model names that are easier to type and remember. We began referring to the non-remote single adjustable shock as the "TT1". This refers to the fact that in many forms of Time Trial racing you get dinged points for remote reservoirs, so these non-remotes are better for that sport, hence TT. The "1" refers to the number of valving adjustments. There are TT1 and TT2 models for most MCS applications - yes, the elusive double adjustable monotube without remotes does exist. We've already sold several sets of TT2s from MCS. And the RR2 and RR3 are "Remote Reservoir" 2 or 3-ways. Get it?



Of course we used our Vorshlag camber plate solution, mated to our custom built 60mm radial bearing upper spring perches. These worked perfectly, giving the car an extra .75 degrees of positive caster over stock (by moving the strut pin backwards). The camber setting range is huge, and at this lowered height we were able to get a max reading of -3.4° camber in the front and -2.6° rear (with the stock rear arms). Our technicians corner balanced the car and the final ride heights at 13" front and rear, approximately 2 inches lower than stock. And yes, it clears the big 255/40/17 BFG Rivals with ease.

Now, when could we find a competition event to run this in?? There was a Texas Region SCCA autocross (Aug 18th, 2013) only a few days away, so Matt and I signed up...

What's Next?

Well this forum update has already run far too long, and I barely covered the MCS TT1 install. Sorry - it was such a long wait getting proper coilovers on this car, you have no idea. I am going to cut it short and cover the rest in another installment in about a week, before we head off to the NASA National Championship event to compete in our TT3 Mustang (we're thrashing to finish up some front aero work on that car in our shop this week) and visit with other customers there.


Left: The BRZ with MCS shocks was surprisingly fast at its first autocross. Right: MCS RR2 remote doubles being installed onto an FR-S at Vorshlag

In our next BRZ Project Thread update I will show details of another set of 17x9" wheels we tested, how a set of 255/40/17 BFG Rivals felt, cover an autocross event we ran in the BRZ with 2 drivers, and show off some MCS RR2 shocks we're installing onto a customer's BRZ track car this week. We have several more autocross and track events planned in the car this year as well.

Thanks for reading,

[juxt3r]

Good read! Looking forward to further updates.