Vorshlag S197 Development Thread

[Vorshlag-Fair]

continued from above

JAMIE BECK'S S197 - FROM STREET CAR TO RACE WINNER

We have done a lot of work to Jamie's S197 race car over the past 5 years and I wanted to continue along with the upgrades we performed in this thread. In my last post from July 2015 I showed an upgrade on Jamie Beck's S197 Mustang where we went from AST monotube single adjustables to MCS Remote Doubles.



This was back when he was getting more serious about his dedicated track car, which we were converting into the W2W car it is today. He was running more and more HPDE events, getting faster each month, but still running on 315mm BFG Rival-S street tires and 18x11" wheels. This tire was chosen to give him more track time per set, and they were managed like a race tire (as the Rival-S and RE-71R should be). These are a little easier to manage than a Hoosier R7 or especially A7 (he uses both now for race and quali sets).



This car was still running the 14" 4 piston Brembos at the time, too. We had been managing the brake caliper/fluid temps with brake cooling but it was still going through front and rear rotors and pads very quickly.



The car was already converted from street car to W2W full safety gear. Full gutted interior, full roll cage, seats, harnesses, fire system, race defroster, remote power cut-off. We did the bulk of this work in late 2013, and he enjoyed running the car with the safety these upgrades provided at local tracks like ECR, MSR-C, TWS, etc. He was on track 1-3 times per month, getting more familiar with these tracks, and of course more seat time.



UPGRADED HALO STYLE SEAT

When we first converted this into a race car we supplied Jamie with Cobra Sazuka seats. We had them in our car and in our showroom, and they are a great seat for an intermediate driver or dual purpose HPDE/street car. But as Jamie's lap times dropped he wanted a more secure seat.



The next step up from this seat is one with a head restraint built in, or a "HALO" seat. We moved up to this in our S197, even though it was a "street car" and only had a 4-point roll bar. I really liked the added safety of the Cobra Evolution seat we added - also moving up from the Suzuka seat. At the time we were selling more Cobra seats but we were transitioning over to more Sparco seats. We also use a smattering of RaceTech, Corbeau, and some OMP seats as well.


Cobra Evolution seat that we ran in our 2011 GT has head restraint built in with these "visibility" holes, which were handy

Sparco make three series of seats with HALO style headrests. We keep two of these in stock so people can "test sit" and see which fits them better. As similar as these seats look, they are very different once you sit in them.


The Circuit (2nd from right) and Pro-ADV (far right) are 2 of the 3 common Sparco HALO seats

For my torso length the Circuit seat style fits me better. For Jamie it was the PRO-ADV. The differences is in the base, with the Circuit having another 2" of height hidden in the bottom. We want to see the shoulder harnesses holes right at your shoulders - not inches above (bad) or below (worse), to get proper belt contact with your body.



So we upgraded Jamie to the PRO-ADV seat, which is a more serious seat for more serious race cars. His Suzuka was legal, but the HALO seats will crash better and they have more shoulder support for hard lateral turns. As he progressed up to Hoosiers it was a welcome bit of support, too.

WEIRD REAR PAD WEAR = CLOCKED WRONG

One of the many times we changed rear pads before his next event we saw the rear pads worn all kinda of crazy on Jamie's car...

Brad took these out and came to show me - wow! How did that happen?



Its actually pretty easy to do. As you compress the piston on the rear sliding caliper on the S197 Mustang it has to be turned with a tool that has two tits that fit into the slots of the piston. These must be "clocked" properly to line up with the pad, otherwise they will get into a bending moment and once they get hot they can warp like this. Somebody changed pads track side and they didn't line up the two tits. So if you ever see this (we have seen this several times since) just line up the piston.

DIGITAL DASH UPGRADE

The stock gauges in an S197 leave out a lot of data, and with a smaller diameter race steering wheel they can sometimes be blocked...



A Motorsports digital dash was an exotic thing just a few years ago, but it has become more mainstream - especially in cars like the late S197 that has CANBUS outputs from the engine computer.

continued below

 

[Vorshlag-Fair]

continued from above



These can be mounted in the stock gauge binnacle or right out on the column (more common), to give better visibility with a small steering wheel or altered driving position. This is actually more of a benefit than you might think. The bright LED warning lights and progressive color LED shift lights are very handy, too.

The AiM MXL we helped Jamie pick out also has an external GPS, data acquisition (acclerometers/GPS/CAN data), predictive lap timer and on-board memory - so it can display everything the CAN system outputs, you can set up warnings and alarms, the user can scroll through different screens to see more data on the fly, and of course you can see your actual & predictive lap times.



It took Ryan less than 3 hours to make a bracket, mount the digital dash, connect it into the CAN wiring, program the screens and alarms, and wrap up the install. Very easy compared to running discrete wires to all new sensors for individual gauges - which can eat up 8-10 hours or more. Keep that in mind when you are thinking of "adding gauges" to a modern car like this that has CAN... the factory sensor data is all there for the taking!

TIGER RACING HOOD

In this same round of mods we installed a vented Tiger Racing fiberglass hood and AeroCatch hood latches to secure the front - in place of the factory 2-step, cable release hood latch.



And I'll be honest - I'm not a huge fan of this particular hood. The vented openings are in weird places, too far back for proper ducted venting. But for a "bolt it on and go" hood (without the effort of adding a radiator duct box) it does a decent job of getting some heat out of the hood.

Jamie bypassed some potential issues in two ways. First, he picked the fiberglass instead of the carbon fiber hood. We've heard of too many CF hoods from this company cracking. The fiberglass version is cheaper, heavier, but seems to be more durable over time. Second, he bought one pre-fitted, pre-painted, and used. One of the painters I use has installed a dozen of these and says they need to be left in the sun for a week to "stabilize" (shrink) before he will do the bodywork needed to fit these to a car. This one had already been on a car for a while, had "settled" and been painted, so a huge time savings.



We adding the AeroCatch lathes to this one, as we have a lot more confidence in these and have used them on dozens of cars over the years. The "push lock" style latches we used on a previous S197 are a royal PITA to line up every time you close the hood, and are finicky to open. These just work.



Ryan takes the time to install these right. First he marks the areas with painters tape so the alignment of the centerline and proper spacing for the four latches can be marked. The pack of the package has a cut-out template that is easy to trace onto the tape. He then uses the hole saws of the exac diameter to make the two holes, then connects them with a body saw and grinds out the oval to perfect. A shop vac is handy during cutting to keep dust from going everywhere - including your eyes and lungs! Still use a respirator and protective eye wear, as shown.



You have to cut an even bigger opening on the inner layer of composite, to be able to access the hardware to bolt the AeroCatch latch in place.


Left: On Jamie's Mustang we used the exposed flange, top mount AeroCatch version. Right: On our car we used the smooth mount

We now always use the "exposed" upper flange version (above left) of the AeroCatch latch, not the "smooth mount" version. We used the smooth mount on my red 2011 GT (above right) and you have to be SUPER perfect on the install or there is a visible gap to the latch. The outer flange of the exposed style is also a bit stronger.



Adding and aligning the pins is tough, I'm not gonna lie. It takes a lot of mock-up, measurement, some alignment tricks, and some welding. Ryan uses four little raised spots from the radiator support that normally have rubber "bumpers" for the stock hood to weld in a nut that is threaded to fit the AeroCatch pins. These have to line up perfectly in height and angles in 2 axes to fit the hood latches when closed.

NEW WEIGHT SETUP

The new setup from the coilover swap and other mods listed above got the car into the 3400 pound range. The weight below is with half a tank of fuel (the lowest we can run in these cars with a stock tank) and driver.



The "ballast" of having a 1/2 tank of fuel you can never use became critical when the car and driver went into NASA ST3 class, which we solved with a surge tank. I will talk about this and more in a future post.

WHAT'S NEXT?

We will show more work on Jamie's ST3 build in the next installment, as well as some other S197 Mustangs we have tackled.



This track driven S197 got a similar Tiger racing hood (it fit the needs of this car) but instead of a rear wing we built a spoiler for this car. I will show the steps in that next time.

Thanks for reading!

 

[zquez]

I'm looking forward to reading about the surge tank you installed on Beck's car.

 

[Vorshlag-Fair]

Project update for January 29th, 2021: It has been a little while since we updated this S197 development forum thread, as we have not had an S197 "shop car" since we sold the red 2011 in 2015. We have done a lot of S197 development since then, and just brought another S197 into the shop for development earlier today (LS swap). But I'm not going to cover those other cars today - just this one.

RECAP OF JAMIE BECK'S 2013 MUSTANG

I am going to cover a car in more detail that we briefly covered in this thread before, but we skipped a LOT of the work we did to this car from 2014-2018. This update shows the development and class progression of Jamie Beck's 2013 Mustang GT in much more detail. Let's back up 3 shops ago and start where this car went from street car to gutted, safe, caged race car.



We worked on Jamie's Mustang a little in 2013, but in 2014 we turned this from a street driven dual purpose HPDE car (above) to a wheel to wheel race car, starting with some major work we begun at our K Avenue Plano shop.

2014 UPDATES



In July 2014 we took this car in, pulled the roll bar, fully stripped the interior, and got the starting weight (sans seats) down to 3276 pounds. This Track Pack 2013 GT car already had AST coilovers, 18x10" wheels, Whiteline Watts, and some other suspension upgrades.



It was the first car my then new hire Ryan caged at Vorshlag, and it was amazingly good work - still one of the nicest cages to come out of our shop. We also installed a lightweight heater/defroster, fire system, and more.



The Mustang was not rated for wheel to wheel racing in NASA, and the added wing made it more competitive, but Jamie spent the next 2 seasons gaining confidence, seat time, and getting some driver coaching in HPDE settings.

2015 UPDATES



In 2015 we upgraded his Cobra Suzuka seat to a Sparco ADV "halo" style seat, with the upper head restraint. We also changed out a Whiteline upper control arm with the Multimatic spherical version, with another spherical bushing added to the axle side.



He continued entering HPDE events, and used full safety gear, as he progressed up the ladder towards W2W racing. Seat time, coaching, etc.



Later in 2015, with his goals of W2W racing closing in, we upgraded the AST single adjustables to MCS Remote Double adjustable monotubes. There were some other changes to the hood (fiberglass vented design with Aerocatch latches), custom endlinks for the WL bars,



The stock oil pan was swapped out for a larger capacity road race pan, and the stock trans mount bushing was updated with this steel version we built.



The first Getrag MT82 let go, so a replacement and fresh Exedy clutch went in in late 2015.



2016 UPDATES

For the start of the 2016 season, it was time to move from 18x10" wheels and 295mm tires up to 18x11" wheels and 315mm tires - still 200TW for now, to maximize seat time costs.



After months of events and brakes starting to be a concern, the end of the 2016 brought an upgrade to Powerbrake 14" 6 piston front brakes, 4" brake ducting, a new brake duct inlet, and AJ Hartman dive planes.

continued below

 

[Vorshlag-Fair]

continued from above



The end of 2016 saw a move to Hoosiers and Jamie earned his provisional "R" license for NASA Wheel to Wheel. As you can see it initially started out in ST2 class...

2017 UPDATES



By 2017 began running in NASA Texas season, running all season in ST3 with 377 whp avg with a stock Gen I Coyote 5.0L engine, stock cats, and stock manifolds.



During the 2017 season we upgraded the plastic 302LS splitter to a fully 8" deep and much wider custom splitter, which we built from 3/16" aluminum. The splitter struts were mounted to the Ford Racing bumper beam he had installed previously at another shop, which already had torn the front bumper cover at the tow hook mount. I am not a fan of this bumper beam.



The splitter struts passing through painted part of the bumper cover wasn't my favorite thing, and we had done the same thing to my 2011 GT. Something just seemed off, but I let it go at this point. The bumper beam underneath was so narrow that there wasn't a lot of options. Ballast was run all season in ST3, bolted to a ballast rack we built in early 2017.



A typical wheel to wheel weekend with NASA usually involves an optional Friday practice day of 1-4 sessions, Saturday is Practice, then Quali, then Race, and another Race. Sunday is a repeat of Saturday. LOTS of time in the car, and when its hot you need some help - like this cool suit system we added in June of 2017.



By August of 2017, after the 2nd Getrag MT82 exploded, we installed a T56 Magnum XL (and changed rear gearing back to 3.73) and removed the stock cats, but he was still able to run ST3 with the right ballast.



The replacement flywheel was lighter, and with another Exedy clutch more pounds were dropped during the trans upgrade.



The 3.31 gears came out and a new set of 3.73 gears were installed. We also plumbed up a transmission cooler to the T56 Magnum XL, to protect that transmission investment for years ahead.



A Tilton pump was used and the AN hoses were routed to a cooler behind the right rear tire. A deflector was built and placed on the "tire side" to keep the cooler from getting sprayed with dirt and rocks.



A lot of track miles had racked up on the stock catalysts, and this was no longer street legal anyway, so to remove risks of a burned/blocked cat we replaced them with these "test pipes". We don't do this on street cars, EVER, but for this dedicated race car it made sense.



At the end of August 2017 this transmission and other associated work was done. The above weight is without driver, ballast, or fuel.



continued below

 

[Vorshlag-Fair]

continued from above

In October 2017 the Mustang was in for some additional AiM sensors (brake pedal sensor, oil temp sensor, etc), some fresh front hubs, cool suit wiring repairs, some trans pump wiring (now it runs automatically, with key on), and a new corner balance (above right) with ballast, fuel, and driver weight included. 3765 race weight with all of the ballast.



At the last race of the 2017 season, at NOLA, Jamie was setting a good pace. He was leading ST3 class and a back marker blocked him and they collided. Or something like that. Anyway, the Mustang fared a lot better than the other car, but still took some damage - and he finished the race. Jamie and some fellow racers did some post-race repairs, reattached one of the splitter struts that broke off at the Ford Racing bar, and finished the next race also. But not it was in the shop in November 2017 for repairs...



We removed the damaged bodywork and reinstalled the replacement LF fender, bumper cover, and repaired hood. We also repaired the bent frame horn on the left front. My earlier dislike of the narrow Ford Racing front bumper beam was proven true in this light accident - the LF corner took all the brunt of the impact and destroyed the headlight, bumper cover, fender, and hood. The hood was repaired (sort of) by a shop that we don't know or work with. We had some trouble fitting them, but we managed to get their repaired and replacement bodywork reinstalled.



To remedy the design issues with the now damaged bumper beam, we replaced it with this custom built version that was rolled and then bent to match the shape of the bumper cover. This much wider design should help protect more of the bodywork if the car is ever in another accident. It was built by one of my fab guys at the time, Aaron. Sadly he left after only half a year (got a good factory gig with really good benefits) and he was sorely missed.



Aaron was able to shorten and relocated the existing splitter struts (FTR) and make a much cleaner pathway for each one to mount to the new bumper beam. The stock lower grill and the foglight / brake duct openings were used for these pass-thrus, and not through the paint.



Proper, thin aluminum sheet radiator inlet ducts were also built to go with the replacement Mishimoto radiator. This seals up the front upper/lower grills with the radiator, as all of the stock plastics were smashed. Aaron also added this tow hook extension to the curved bumper beam, which reached down through thr lower grill opening to mount a proper tow hook.



The detail work Aaron did was simply amazing - the stainless mesh screen in the lower grill (to stop bugs and klag from fouling the radiator fins), the bumper beam, the splitter strut routing - it all really came out top notch.



The repair work for the crash damage, plus a host of other upgrades, was complete at the end of November 2017 and he was race ready again. I was so impressed with this wider, curved bumper beam design we have since added them to numerous race cars we have built.



JACKING RAIL REINFORCEMENTS

Being able to safely lift a corner or a whole side of a race car at the track, safely and quickly, is important.



Back in late 2016 we added this Watson Racing Jackplate kit, which is a great deal for only $75. Donnie who worked for me in 2016 did the stitch welding, and Jamie wanted this point placed on each side in the middle of the rocker seam - for a quick "one side" jacking point.



Well by December 2017, Jamie had realized that it would be helpful to have a jacking point closer to the front, so Aaron took some 1.25" square tubing, sliced it along the top edge, and stitched that over the rocker seam as shown.



With these welded in, seam sealed, primed and painted the rocker pinch weld is protect, and a notch was added to the plastic lower rocker panels to be able to access this jacking point.



One last update done in December 2017 was this dead pedal, which we added to the false floor already installed on Jamie's car. Aaron made a pattern, transferred to aluminum, bent it up, bolted it in place, and added grip tape to the surface. Still with plenty of room to the clutch pedal and built around the cage tubing there.

2018 UPDATES

In 2018 the ST3 field shrank, and Jamie had a lot of friends running in ST2, so he switched to this class. The power to weight ratio then changed from 10:1 in ST3 down to 8:1 in ST2 (before modifiers). This is a big jump...



The Mustang was back at Vorshlag briefly in February 2018, after he had another shop install long tube headers. We normally would have done that work but we were buried in work before our shop move a few months later. The peak power was up to 445 whp and 409 wtq, which is a great. Using NASA's average hp formula it showed to be 417 whp average.

LET'S RUN THE NUMBERS FOR ST2 (2018 Season)



With the new and improved average power dyno test (417 whp avg with long tube headers), using the Super Touring 1-4 class rules, the new minimum weight are easy to calculate.

• Super Touring 1 (ST1) = “Adjusted Wt/HP Ratio” equal to, or greater than, 6.00:1
• Super Touring 2 (ST2) = “Adjusted Wt/HP Ratio” equal to, or greater than, 8.00:1
• Super Touring 3 (ST3) = “Adjusted Wt/HP Ratio” equal to, or greater than, 10.00:1
• Super Touring 4 (ST4) = “Adjusted Wt/HP Ratio” equal to, or greater than, 12.00:1

The rules are pretty straight forward for ST1-ST6 classes, and the spread between the classes has been cleaned up in the last few years - its an even 2 lbs per whp jump from each class. 417 whp avg x 8.0 pounds per hp = 3336 lbs min weight. But then there are weight modifiers...

continued below

 

[Vorshlag-Fair]

Continued from above

Since that 3336 is above the threshold for "running lighter than 3000 lbs" penalties, so there was actually a bit more he could have gained (weight bonus) - if he could run even more power. Which with a Coyote, becomes a real issue - the "reliable" power limit is about 450 whp on a Gen I engine. This car doesn't have a sequential, dog box, non-DOT tires, or any other bonus or penalty modification. When he ran the car in ST3 at over 3800 pounds race weight (with ballast, fuel and driver) he had a +0.5 bonus (from total weight) to his 10:1 power to weight ratio (9.5:1), so he could run even more power - but not the new 417 whp average after adding headers.

3700 pounds / 417 whp = 8.87 pounds per whp (ie: the REAL number)

With the current minimum weight goal we could get the car + driver + minimal fuel load (around 3700 lbs) and the 417 whp avg his ACTUAL power-to-weight ratio was really 8.87 pounds per hp. That is solidly RIGHT BETWEEN classes ST2 and ST3. I ran into the same problem in my 2018 Mustang when running in TT3 and TT2 for 2 seasons (which use the exact same rules as the ST classes) - as soon as we upped the power level, the power and weight calculation always put this car in between these two classes' numbers, too. That's not a fun place to be when you are competing against cars at the bleeding edge of a class' p-to-w.



In both Jamie's S197 and my S550 (above) there was no way we could get to the limit of the power-to-weight of the ST2/TT2 class. The chassis don't get light enough and the Coyote engines just don't make enough power to reach that (it would need to make roughly 550 whp peak, and Coyote engines built to take that live "ones of laps" at that level). At Jamie's car's real 3700 race weight, to be at the limit in ST2 he would need to make....

3700 lbs / [ST2 8.0 - 0.5 "bonus" = 7.5 pounds-per-whp avg ] = 493 whp average (theoretical limit)

So at 417 whp avg, he would be running effectively 76 horsepower under the limit of the ST2 class. Getting DOWN to the minimum weight calculated the other way (3336 lbs) was not possible without MAGICAL means (you would have to cut away too much - there just isn't a way legally to get an S197 that light in Super Touring). He knew this, and just decided to run the car in ST2 "heavy" at 3700 pounds with driver, or 364+ pounds overweight. We did the same thing in our 2018 GT, with fairy dismal results. But he still wanted to go to ST2, so ALL of the ballast could come out (the ballast rack in the trunk) as well as unnecessary fuel ballast.



Everyone who has tracked an S197 hard knows this - the OEM saddle tank is notorious for fuel starving BADLY when below 1/2 tank in a left hand corner. To remedy this and add much needed ballast for ST3, we asked Jamie to run his tank nearly full before every session (which is nearly 100 pounds of fuel). Now, with a huge minimum weight drop it was time to remove the fuel ballast, and to do that we needed to remove the fuel starvation issue at lower fuel levels.



We didn't want to re-wire the car to use an aftermarket EFI system, so instead the stock pump was kept in the tank as a LIFT pump to then feed this Radium Engineering external surge tank, which had its own internal pump and fuel pressure regulator.



Aaron performed the wiring and plumbing work, and without having to re-plumb the whole car or do any EFI magic we were able to get this accumulator system added which allows the stock tank to work "down to the last drop". The extra capacity of the surge tank is always kept full, so he can finish a race with just what's in the surge tank if needed. In the end the fuel surge tank worked GREAT and it has run flawlessly for the years since we did this in 2018.

2018-2020 HIATUS...

Jamie ran most of the 2018 season in ST2, and did surprisingly well even down power / overweight for the class. But then another out of class competitor somehow missed the big Mustang bearing down on him at Hallett in the Summer event, turned into him, and there was another incident. Maybe the car should be painted hot pink and have a red flashing light on top??

With all of the costs of wheel to wheel racing, entry fees, travel budgets, tire budgets, and then the previous repairs from the 2017 incident, the costs got too high and Jamie put the car on ice before attempting the repairs. It sat in his trailer for more than 2 years, but in late December of 2020 he was ready for the car to come in for repairs, and his budget had recovered enough to stomach what would come next.

2021 UPDATES

"Don't hate the player, hate the game". Nobody likes paying for crash damage, and we don't like "making money" this way, but its all part of the W2W game.



Just getting the car out of the trailer was tough, and took nearly 2 hours. The RF wheel was busted, the control arm and spindle was badly bent, and a tire was rubbing the inner fender. It wouldn't even roll, so we dragged it out with my tractor while the front end was on skates. Getting into the shop took some work.



Amazingly the same splitter we built back in early 2017 survived another car to car contact, and looked like it would need almost zero repair to be fully functional again. THIS is why we don't make splitters out of carbon fiber or sign shop material - you just LOOK at those funny and they shatter and fly off. This car was DRAGGED across the asphalt on the leading edge of the splitter, onto a flat bed and then into his trailer. It's just a scratch...



The structural damage was more this time - it must have been a bigger hit. The front subframe was bent, a control arm was bent, RF spindle and strut housing were bent, as well as the RF fender, corner of the hood, and one headlight.



We took the MCS dampers off and sent the whole set in for inspection and rebuild/repairs. The new spindle and subframe were quite affordable and arrived new from Ford within 24 hours. After securing the engine from above Brad dropped the front subframe and suspension out.



On Dec 31st, 2020 the new subframe, old steering rack, new spindle and control arm went into the car. Good work for the last day of the year.



In the first week of 2021 the dampers arrived, with the RF housing replaced and the others rebuilt (it was time). Brad reinstalled the shocks out back and reinstalled the Seals-It 2-piece grommets for the pass-thrus in the trunk.

continued below

 

[Vorshlag-Fair]

continued from above



After the struts were installed a rough alignment got the car to roll. Then a new OMP halo seat we had in stock was installed, since the old Sparco had been reinstalled into one of Jamie's Miatas.

By January 6th the car was repaired enough to go to the painter - Heritage Collision who does all of our repair work - for bodywork and paint.



The crew at Heritage did an excellent job sourcing new Ford fender and bumper cover. They also straightened the radiator support and reworked some poor bodywork done by another shop. They painted the whole right side of the car, replaced (and matched out lightening work) the passenger door, and blocked/painted the fiberglass hood. I stopped by January 19th to take the pics above and discuss the repairs.



The Mustang returned to us at Vorshlag on January 25th and we got to work. The front nose needed a lot of little tweaks and mods to fit around the splitter struts, to add the dive planes, to install the brake inlet ducts, so I asked the painter to just "set it in place". We kept the old bumper cover to use as a template for many of these items and changes we needed to make.



While the car was at the painter's we received some replacement parts needed: the Maximum Motorsports bump steer tie rod kit that was bent was installed (above left) and the new Safekraft belts were also put in - as well as a dozen other little things.



We knew the bumper beam took a hit, but after the car was pulled and everything straightened on the chassis it was more apparent. The RF corner was really bent inboard and the whole beam had tilted "up" on the mounts.



The only things to hang off of this bumper beam were the tow hook (which was missing/destroyed) and the splitter struts, so we didn't have to be perfect within 1/16", but the whole side was off by inches. It took some drastic repairs but Zach cut the flanges flattened out and the bent section spliced, repaired, and plated for strength. This DOM tubing is mega strong, by the way, and definitely absorbed some energy in the impact that could have bent the frame or worse.



There was a lot of little detail work done to the bumper cover - the grills had to be repaired and remounted, the dive planes installed, the brake inlet ducts repaired / drilled / installed, and more.



After less than 4 days of work the bodywork was all reassembled, the bumper beam repaired, the splitter reinstalled, and the fender liners repaired and installed.



Brad even tackled some maintenance - the pads were checked, full nut and bolt of the car, brake fluid was flushed and bled, things along that line.



The nets we installed in 2014 were now out of SFI spec (5 years) so replacements for those were installed as well, to make everything up to date.

continued below

 

[Vorshlag-Fair]

continued from above



Instead of replacing the 4" brake duct hoses every few races Jamie listened to our advice and we installed our S197 brake cooling deflectors onto the control arms. We installed a new tow hook to replace the damaged one, too.



We hustled until after 5 pm on the 28th but in almost 4 weeks we had done our repairs, sent the car to paint, they did their thing, and we had it race ready once again. Jamie was super happy to get the car back after the 2.5 year hiatus and signed up for a March race and had a February coaching/test session scheduled as well.



LET'S RUN THE NUMBERS FOR ST3 (For 2021 Season)

Jamie's car ended up at almost 3500 pounds when we finished the repairs on January 28th, and here's where we need to run the numbers again. Happily this time Jamie is looking at ST3 once again, and we know the car can be more competitive there - It will take both some added ballast to get the weight up AND a re-tune of the engine to get the power down. We will run numbers both ways for him before his dyno tune that is scheduled for next week.



With the nearly 3500 pound weight above (low fuel, no driver), let's assume a 3750 pound minimum race weight and check ST3 and ST2 numbers at various power and ballast levels. ST3 has one different rule than ST2 - the "BTM Aero Bonus" - but Jamie's big wing, dive plane, massive splitter setup is NOT anywhere close to the Base Trim Level aero for a 2013 Mustang GT. So that can be ignored.

With Hoosier R7 or A7 tires (qualifying on As, race on Rs):

• Option 1 for ST3: 417 whp avg (current) x [ 10.0 pounds per whp - 0.5 bonus for race weight = 9.5 ] = 3962 lbs
• Option 2 for ST3: 395 whp avg (returned down) x 9.5 = 3750 lbs (no ballast needed)
• Option 3 for ST3: 406 whp avg (split the difference) x 9.5= 3857 lbs (107 pounds of ballast needed)

Option 1 is pretty heavy and would require 212 pounds of ballast. The weight rack could take that but the consumables (tires, pads) would wear faster than ever before. Option 2 is no additional ballast but the average power would have to be chopped back 22 whp, which is a chunk. Option 3 splits the difference on ballast (107 pounds needed) and power loss from current levels (only 11 whp reduction). If this were my car, that's the weight and power I would run. We regularly ran that heavy in TT3 (3802 min) in our 2011 Mustang back in the 2014-15 seasons, and still won every event we entered. Of course we had 335/345 tires, which helped.

Jamie is thinking of running with non-DOT Michelin race tires, for various reasons, and that effects the numbers considerably. I don't think the "juice is worth the squeeze" with these tires, so I wanted to show the numbers for this case also. As you can see in the chart above, the non-DOT penalty in ST3 is pretty large at -0.7. So that more than wipes out the "3750 pound" bonus of 0.5, for a net power-to-weight ratio of 10.2:1.

ST3 with Michelin non-DOT race tires:

• Option 1 for ST3: 417 whp avg (current) x [ 10.2 pounds per whp] = 4254 lbs (+504 pounds of ballast!)
• Option 2 for ST3: 395 whp avg (returned down) x 10.2 = 4029 lbs (+279)
• Option 3 for ST3: 406 whp avg (split the difference) x 10.2 = 4142 lbs (+392)
• Option 4 for ST3: 367 whp avg (3750 / 10.2) = 3750 pounds (no ballast)

None of of these are great options. The ballasted minimum weights are pretty dang high for a 315mm tire to last any meaningful amount of time. The 4th option with effectively no ballast is going to cost him 28 whp on the non-DOT tires vs the same ST3 setup on Hoosier R7s (367 vs 395 whp).

Let's run the ST2 numbers with non-DOTs, below. That is jumping up to 8.0:1 base ratio class, then taking the + 0.5 bonus, but then a -0.5 non-DOT penalty (this penalty is not as harsh in ST1/ST2). That leaves it at a straight 8:1 ratio, which is still too far away for the weight and power he has to start with.

ST2 with Michelin non-DOT race tires:

• Option 1 for ST2: 417 whp avg (current) x 8 pounds per whp = 3336 pounds
• Option 2 for ST2: 468 whp avg x 8 = 3750 pounds (no ballast)

So if he sticks with the Michelins he is back to running 414 pounds heavy in ST2, or looking for a magic 51 whp average gain - which just isn't possible with the Coyote engine platform - not reliably, not for a road race car, and not without several tens of thousands of dollars of spending for a very custom, short lived race engine. An LS swap with a built race engine would be easier and cheaper - but that swap it is neither cheap nor easy.



Earlier today we began LS swap development for the S197 chassis, but I know Jamie isn't ready for that right now. Still, if he really wants to run ST2, that's the best way to make the power goal to get to the limit of the ST2 class, without drastic weight losses.



That's where we are with the numbers. Jamie has the dyno session scheduled, as well as a race alignment/corner balance at Texas Track Works. I will share later what class / weight / tires Jamie decided to run, and we will support him in whatever route he chooses.

Thanks for reading,

 

[cholmes1]

Incredible work. Excited to read more when the race season ends