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S550 mavisky's "LOUDCAR" Build Thread Profile - S550 Mustangs

Race tires and aero on the car for the first event this weekend. Splitter is about 2.75" off the ground up front and mounted at a 0.5 downward angle. Total invested is probably around 500-600 between the mounts and the splitter and the coating. Holds my body weight easily. We will see how well it lives over some of the dips on course. I expect to remove some material until I get the new Steeda springs on the car.
View attachment 266087

Looking at this photo makes me realize how badly.i need to treat the factory plastics after 5 years of ownership as they're all a little less rich and shiny than I'd like.
At this point it's just a low spoiler while I hunt down a proper trunk lid replacement. For autocross it will be a little front aero heavy but thay should help the current setup. I have a smaller splitter for any higher speed use.
So my response to that is to try and duplicate a proven race setup like the Gt4, that has been in a wind tunnel, and uses a front splitter sorta kinda maybe close to yours.20221210_074914.jpg20221208_170526.jpg
So my response to that is to try and duplicate a proven race setup like the Gt4, that has been in a wind tunnel, and uses a front splitter sorta kinda maybe close to yours.View attachment 84453View attachment 84454

The goal is definitely to go to a wing. The class I run in just made wings available in late December I think. I was in the process of developing a large rear spoiler to offset the front splitter (per the old class rules) when the spoiler I purchased turned out to be too flimsy and unable to support the additional load I'd be asking of it. I'm in a holding pattern now but will likely be working with AJ Hartman Aero, APR, or 9 Lives Racing for a wing before the end of the season.
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Exp. Type
Exp. Level
Under 3 Years
Pretty impressed with them so far. I haven't been autocrossing since the early 2010's so it's been a decade of tire technology I've missed out on, but they have impressive amounts of grip compared to my PS4S.

I shaved around 1.8-2 seconds on our average 56 second courses we run here in Atlanta over the PS4S with no other changes. They also like really low pressures. I run like 28PSI hot in them compared to 35 hot on the PS4S. They seem to come up to temp pretty quick so that's great, although I did read some reviews online of them not holding up the best on long track sessions on heavy cars like ours.
Hello again.
At the track now and started at 25 cold. What is your cold pressure(s)?

contemplating 23-24 cold
With the 305 Kumho's and our air and ground temps today I wasn't able to get them hot enough to need to bleed air until run 3.

Car ran well, but the new splitter took some abuse due to a big dip on the course being placed right in a dip before the finish. Splitter itself is totally fine, but the aluminum mounting pucks for the Longacre splitter rods are just about nonexistent after today. Should be fun getting these screws out. Looking at some titanium skids to protect them in the future.

Exp. Type
Exp. Level
Under 3 Years
With autocross I start at 28 ans aim to keep it there all day honestly.
Okay. I do see what you meant by these tires liking low pressures. Didnt touch near the sidewall until I started at 23 cold (at -3* camber). I tried 25 at first and coming off, they were at 32/33. Tires were not bad for a 25 min session.
Hot ALWAYS dictate cold..

Even at autocrosses
This makes sense now and I see why pressures are taken when the car comes off track. There was a Trans Am/ GT1 car out there testing and I was wondering why there were taking pressures after each session. Thank you
These may work as well.

Currently looking at these. Seems the Titanium would be a little heavier, but also much stronger than the Carbon.

Also looking to get more info on these from AJ as I always like supporting site vendors and members if their products meet my end goals.

Swapped out the Ford Racing spring and swaybar kit for a full Steeda Suspension.

Dual Rate Magneride Springs
Compeition Swaybar Setup
Adjustable Endlinks front and rear
Front strut mount opened for further camber adjustment with Steeda camber plates (plates were already on the car)
Rear camber adjustment mount

At this point the entire suspension and bracing setup is all from Steeda.

Unfortunately we're boarding a cruise ship next weekend when our next event would take place but trying to get an alignment next week to get the car ready for when I get back. Maybe try and squeeze in a PCA event until our next regional SCCA event the first weekend in May.

Good news is that the car is much stiffer (as expected) based on standing on the front splitter and bouncing the car and it's a bit higher off of the ground too. I was bottoming out bad at my first event with the new splitter and even after adding some Professionally Awesome titanium skid pucks, it will be nice to have a little more ground clearance.
Another weekend of racing, but the weather caused me to shift my plans. Was originally going to attend a fast and open autocross with the Peachstate Porsche Club down at the place I usually run with SCCA at Atlanta Motor Speedway, but the weather was going to call for heavy rain and lightning all Sunday morning. With the real possibility of a complete rainout and potential cancellation of the event due to lightning I decided to look elsewhere. Atlanta Motorsports Park (considerably closer to my house than Atlanta Motor Speedway) was going to host their first AXS autocross series. They run this on a portion of their paddock and their skidpad which means that it's going to be very tight. I knew this going in but figured it might still be a good shakedown event for the changes.

The course was so tight I never had a good place to even change into 2nd gear and instead chose to simply buzz the limiter in the fastest section instead of wasting time changing to 2nd then back to 1st. That being said I was still able to hustle this 3,750lb behemoth through the course faster than all but one other competitor and not only won my class, but put down the 2nd fastest time of the event behind a 1,500 lb Honda CRX on slicks at all 4 corners. Below is the fastest run of the day and you can see just how tight this course is, but the new suspension really helps the car rotate at will. Will be interesting to see how this translates at higher speeds as it may be a little too willing to rotate.

Sadly there was a little bit of carnage with the front splitter as the course contained a fast downhill section that saw heavy braking into the dip. The titanium splitter pucks under the splitter kept the actual splitter free from damage, but I think I may have them mounted a little too far forward and instead the splitter support rods took a lot of abuse. Luckily I have spares at home, but will probably look into some of the alternate options from either AJ Hartman or Professional Awesome.


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