Project LOUDCAR - 2018 GT350 - J0006 - Autocross focused street car

[mavisky]

Swapped out the Steeda rear camber adjusters for the SPC camber arms. The arms are lovely, but the guys doing the alignment weren't the happiest. Sent the car in with them at max negative rear camber and the car was at like -3.5 degrees. As such they had to play around with re-positioning the inner hex to get it right but finally got the rear settled at around -2 dergrees on both sides with a slight amount of toe-in. We quickly confirmed the front alignment settings (-3.2 degrees camber and a mild amount of toe-out) and I went to attend the AXS autocross series at Atlanta Motorsports Park again. The track was again incredibly tight with me just buzzing the limiter in 1st a few times at the end of the longest straight but with the complexity we still had a fairly long course. I ended up winning my class and running the fastest time of the day with a 49.5 second run which give you an idea of how tight the course really is if you're taking that long and it's all in 1st gear in my car.

Anyway, here's some photos from the event.

New SPC arms going in.

Throwing some sparks from the titanium skid pucks on the bottom of the splitter.

Here's the only video I was able to capture from in car.


and from outside the car

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[mavisky]

do you have any more pics of this SN?

Yea, car started out pretty basic and ended with a solid amount of bolt-ons. Intake, cam, heads setup with some interior and exterior mods and suspension to go with it. Honestly didn't take as many photos of this car as I did with many of my others because I never truly fell in love with it, although it certainly had some redeemable qualities.

IMG_1421_zps539a301e by Kyle Mavis, on Flickr

DSC_0221 by Kyle Mavis, on Flickr

DSC00959 by Kyle Mavis, on Flickr

DSC00958 by Kyle Mavis, on Flickr

DSC00957 by Kyle Mavis, on Flickr

 

[mavisky]

Latest event and another 1st place finish and fastest time of the day.

2nd fastest run of the day as the footage for my fastest run was corrupted. Run was starting off decently but over the first crest the car crosses a set of steel plates for the tracks wet skid pad and this threw the car into a fit. The car threw a service stabilitrac light on the center gage cluster and moved the car from Track mode to Normal mode. First time I've ever had this happen and this was the only run it happened on all day. Still resulted in one of the top 3 fastest times of the day. for some reason the audio also glitches about halfway through the video and dropped in volume.

The run after this the system stayed fully functional and was able to drop a full 2 seconds off of my time. In the end I was able to set the fastest time of the day at that point by about 3 seconds so called it a day and headed home to shower and pick up my daughter to bring her back for the trophy ceremony. One other car ran an even faster time later, but with a cone penalty he slid back behind my time overall. Would have stayed and got a few more runs to get my money's worth, but I have an event on Sunday the 13th with the Peacthree Porsche Club, an event on the 20th with the SCCA, and a local one our city puts on the 25th and 26th where the fastest car gets $500. Needless to say saving the tires a bit was in my best interest today.

 

[mavisky]

Ran my second event of the weekend yesterday. A lot of time standing in parking lots in 95+ Atlanta heat.

Ran this event at Atlanta Motor Speedway where I usually run with the SCCA, but this event was with the Peachstate Porsche Club. Much faster course (actually had to go to 3rd on one of the straights) and a nice flowing course that still saw the best times at right around the 1 minute mark. Compared to the 6 runs we get with SCCA we got two sets of 5 runs with PCA which was appreciated. It turns out with this event it was needed too as I was struggling on the faster course with so many of my recent events being much slower. Braking points were off, had a massive spin on one run, and generally struggled to find speed. While they have a ton of different classes for all of the different Porsche models there, the rest of us are lumped into either stock or modified non-Porsches so I had no idea what I'd be up against. In the end I was in 3rd most of the day in class behind my buddy in his well build 2014 GT and a guy with a supercharged Miata on some sticky tires. Ended up putting down my fastest time on my 10th run of the day to just sneak ahead of the Miata and claim 2nd. Waiting to see the final results for the overall times, but the guys in the Cayman GT4's and Boxster Spyders were putting down some seriously fast times in their lighter PDK equipped cars with stickier tires than I run in my usual classes.


Edit- Results came in and just snuck out 3rd place by 5/1000 of a second over one of the 718 Boxster Spyders.

Fastest Lap


Big spin with a scary moment of the car pointing at some massive concrete barriers and a 6" curb.

 

[WItoTX]

What splitter is that? I might have missed it in your thread.

 

[mavisky]

What splitter is that? I might have missed it in your thread.

Custom built this offseason using a special type of plywood for concrete forming due to it's epoxy content and water resistance along with some molded in GT500 style splitter fences from ZL1 Addons. I figure i'm about $800 all in after the mounts, splitter materials, coating, and the titanium pucks and AJ Hartman spring loaded supports.

 

[mavisky]

Put in another SCCA event two weekends ago and finished 2nd again behind my buddy in his 2014 Mustang GT. Need to get back ahead of him as he's now got one more class win than I do this year after I missed an event.

I'm going to be softening the rear bar as the car is a bit twitchy on corner exit and running the front and rear bars on max to try and limit roll has helped some with transitions, but I've had to really tip toe around corner exit. This high bar setting paired with the super high rear spring rates is probably what led to the spin from the Porsche event. I'm leaving the front bar where it is for now but I'll be looking to add Steeda's front ride height spacer kit which should raise the front 1/2". This should transfer some weight back to the rear axle (tiny amount), but should also help keep the splitter off the ground. When it's riding the titanium pucks it's basically going to an infinite front spring rate and understeering. It also gets me warning and concerned discussions in grid about course workers seeing sparks under the car while it's out on course.

I'm going to also add in Steeda's DSC controller which should help out some, but eventually I'll need to probably move to a stiffer spring rate up front to keep the car off of it's nose. Wanting to try some stiffer shock valving and the small ride height adjustment for now though.

 

[kz]

What's your current front spring rate ?

Also - have you considered buying a controler from DSC rather than Steeda's (which is locked and you can't really do anything with it other than use their calibrations) and talking to Tim about a map for it ? That also leaves you opportunity to tune it yourself should you ever want to.

 

[mavisky]

What's your current front spring rate ?

Also - have you considered buying a controler from DSC rather than Steeda's (which is locked and you can't really do anything with it other than use their calibrations) and talking to Tim about a map for it ? That also leaves you opportunity to tune it yourself should you ever want to.

I'm on the Steeda dual rate springs right now as they're seemingly the best off of the shelf springs avaialble with a 220-350 rate (which should really be like 300-500 in my opinion).

In regards to the DSC, I don't have the time to second guess everything and I'm more likely to screw things up with the vast array of adjustments available vs taking a solid step forward with the Billy Johnson developed Steeda maps designed to pair with my exact spring and swaybar setup.

If I decide I want to go more hardcore than this I'd likely just remove magride altogether, but don't see myself going that far.

 

[mavisky]

Well wrapped up the final 2 events of the season this past weekend. First video in 2 events as I discovered I had a corrupted memory card in the GoPro, but got that all fixed thankfully.

No major changes to the car at this point. Had purchased a Steeda DSC magneride controller, but for some reason it's not working with my car. Steeda and I are working with DSC to try and diagnose what's going on here and why my car is being finicky. With that in mind I headed out into some of the worse weather we've had all year for two tricky events.

Event 1 was the AXS season finale at Atlanta Motorsports Park. Event started 40 and raining. Given the state of my now year and a half old Kumho race tires, I played it safe and put on the Michelin PS4S thinking I wouldn't be giving up that much grip in the rain and would have a much safer drive to the event. I had also already locked up my class win on season points in all of my previous events, so not finishing top of the pack wouldn't ruin anything major. This strategy worked perfectly until the rain stopped and the course dried. Being the first one on course meant that my runs were almost all in damp weather. Meanwhile the last two heats had runs with an almost completely dry track and were able to put some blistering times down. As such ended up finishing third in class for the day which was only the 2nd time I've ever run at this event and not put down the fastest overall time of the day, much less in class.

As you can see though, definitely still some moisture in areas like heading up the hill after the start. Car grabbed a ton of oversteer trying to put the power down up hill here. Also, due to overcast skies my car was peaking their sound meters. Unfortunately one of the pre-requisites for them building this new racetrack was a sound ordinance at all times that is only removed on July 4th. They're trying to make amends to get this lifted so they were being extra cautious this day. Thanks to the AWE controller though I can force the exhaust valves to stay closed.





Event #2 was the SCCA Champion of Champions event. After getting whooped on street tires, I threw the Kumho's back on as it was dry by my house. When I got to within about 20 minutes of the location, it was obvious it had still been raining some over night south of Atlanta. Another damp 50 degree day with moisture on the ground. Not actively raining, but it didn't dry out until the very end of the day. The issue with this event is that you run 2 different course (reversed, but with some changes) for only 3 runs a piece and my car sat for about 4 hours in between runs. Given the surface temps and gap in runs I was never able to build heat in the tires on the rear and only barely got any temp in the front tires. On top of that these tires are now ancient and without getting smoking hot they're way down on overall grip. You can see how little grip the rear has in both runs as I try to power through the finish.

Damp morning run


Dry afternoon reverse run

 

[mavisky]

Finally swapped out the factory trunk lid and spoiler for a trunklid from a wrecked 2018 GT and added a Verus UCW onto the car. To fill in the holes left in the center I used a carbon fiber filler plate from APR. It's nearly impossible to find a Orange Fury trunklid without spoiler holes of some kind and this one alone took me 2 years to find at a decent price. This allows me to keep the OEM trunk and GT350 track spoiler on the shelf for re-install later if I want. Hoping to get the stripes back on this weekend and then she will be good to go for rear aero.

 

[mavisky]

I've received some questions about why I went with the Verus wing in particular on other forums, so thought I'd mention it here as well.

I asked Verus them about adding a gurney flap to their wing and they say that their testing doesn't show any improvement (which seems odd given that they seem to work on every other wing profile) and I also asked them about a dual element option such as what Nine Lives offers and they only offered me one of their monster $7,000 wings which don't utilize any stock mounting locations. Per their charts the Verus UCW wing is slightly better than the Nine Lives single element at 140mph and 10 degrees AOA with the Verus offering just over 400lbs and the Nine Lives coming in at just under 400lbs.

Once you add the gurney or the dual element kit though the Nine Lives takes a step ahead offering up to 500 or even 600lbs. I'll be running the Verus in it's most aggressive 15 degree setting which should net me around 80 - 100lbs of downforce at 60mph which should keep me on par with what I could have achieved with even the Nine Lives dual element configuration or 3/4" gurney flap.

This is Verus's chart for the single element UCW Wing

Nine Lives Racing Single element wing

Nine Lives with Gurney or Dual Element

 

[kz]

Those are some great looking downforce charts

 

[mavisky]

Those are some great looking downforce charts

How weird. I have no idea what those photos are as they aren't mine at all. Weird copy pasta shit going on. Let me fix.

 

[mavisky]

New tires for the season.


Moving from the 305/30-19 Kumho V730 to a 295/35-19 Yokohama A052. These are the same tires and size that won nationals on a Mach 1 last year in one of the stock classes so they should be worth a few tenths for sure. Will be interesting as this will be the first time my primary competitor locally will be on the same tires and sizing as I am.

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