kellyjmcd
kellyjmcd
5/5/23 4:46 a.m.

So long story short, I missed a call from the Pike's Peak tech director, and my 2023 application (converted Wells Coyote open wheel) was deemed not suitable for pavement; however, I am determined to race this event. I've always loved the 356 Coupe body style, but in my head, I'm thinking that I also really like the redesign of the 935, like Jeff Zwart's car. It is not so far along yet, but I've had this idea for about 2-3 years, and working within a limited budget as a 25-year old I believe I am making steady progress. 

 

Chassis-

DOM 1.5 .095" steel tube, designed in Bendtech, imported into Fusion 360 for the plasma cut pieces. I am very pleased with how the chassis is turning out. The control arms are 1" steel tube with an ID appropriate for 3/4 -20 tapping, for rod ends. I modeled the suspension geometry in 2D to achieve a slight increase in camber under compression, and the inner mounts are adjustable for anti-dive or anti-squat geometry. The suspension uprights are also designed in CAD, I wanted to make them as modular as possible. The upper mount is bolted on, so as to be able to adjust scrub radius with different mounting distances. They fit a Dodge Intrepid wheel bearing, which is a three-bolt bearing with 33 splines. I also designed the rockers, in order to add a provision for a link to an ARB. The aluminum parts and the mounting posts for the rocker were ordered through Xometry and came out awesome after sending some technical drawings along with the 3D model. The chassis needs to stay under 2500 lb to maintain it's legality for 1.5" .095 DOM. 

 

Now, I'm not going to claim I am something which I am not. I am not an automotive engineer. However, I love learning about these things. This project is in good fun and I have been having a blast building it. It has really helped me sharpen my skill set. I am using practical knowledge, ~10 years of W2W racing in NASA, and a lifetime of being around cars to guide my decisions. 

Bodywork-

I am planning on building the body in three carbon shell sections. the middle will be semi-permanently attached to the chassis. I have a decently sized CNC router at my disposal, so I sectioned the model into 4" tall pieces that will fit a 4'x8' foam board. These boards are generic EPS insulation that can be had at Home Depot for around $20 each. I needed to seal the foam mold plug to be able to utilize body filler (polyester resin based). I opted for a mix of mod podge matte and acrylic black paint, to keep track of the coverage and make sure it was completely covered. I then used a lightweight body filler to fill the gaps and smooth the tool marks. I am in the process of making a multi-piece mold for this front end clamshell. 

Drivetrain-

 

Initially, I was interested in putting a 1300cc suzuki chain drive motorcycle engine in the rear of the car; however after seeing how unintentionally well a 5.3L Chevy fit in a mid-engine front config, I think I have made the decision to use the LS platform. The 5.3 is a boat anchor in weight, but is around the same form factor of much more potent SBE LS platforms from Chevy, so when I get to the point of using an aluminum block/more displacement, it is a fairly easy change. The transmission is a GS7D36SG DCT from a BMW M3. Using Maxxecu, I can control the factory mechatronics over CAN BUS. This has become a new up and coming transmission swap, and I'm ashamed to say I fell victim to the hype of HTG Tuning at first. You shouldn't have to fiddle with tuning your transmission and getting it to work right out of the box, more than you would have to with your engine in an ideal world. I am aiming for simplicity in my setup. for the rear, I plan on a winters quick change differential. 

 

Brakes and suspension-

 

Planning on Wilwood Superlite calipers with wilwood discs and hats. I will likely design a ducting system for brake cooling once I get the chassis sitting on all four wheels. For suspension I am using Ohlins KT303 dampers. I may need to adjust springrate depending on loads and curb weight. 

 

 

 

 

Thank you for reading! as much as I'd like to do frequent updates, this is about a ~5 year project for me. I will update this thread periodically though. smiley Like I said, I'm not an engineer. this is my hobby and I have so much fun doing it and get a lot of satisfaction out of it. I can't wait to drive it in a few years. 

 

wheelsmithy (Joe-with-an-L)
wheelsmithy (Joe-with-an-L) GRM+ Memberand PowerDork
5/5/23 6:11 a.m.

Bitchin'

OHSCrifle
OHSCrifle GRM+ Memberand UberDork
5/5/23 6:27 a.m.

Welcome to GRM forum. That's a helluva way to introduce yourself! 

DrMikeCSI
DrMikeCSI Reader
5/5/23 6:30 a.m.

Wow this is great. I love the 356 / 911 mashup.  

DocRob
DocRob Reader
5/5/23 8:38 a.m.

Oh that foam board idea is AWESOME. And I'm stealing it for one of my own projects.

And also this whole thing is awesome. 

californiamilleghia
californiamilleghia UberDork
5/5/23 1:20 p.m.

Great job ,

too late now probably but a lot of the 914 guys are using Audi motors and gearbox , lots of power and low weight , well lpwer weight than a SBC

fouckhest
fouckhest New Reader
5/8/23 11:27 a.m.

Great project, looking forward to following along

kellyjmcd
kellyjmcd New Reader
5/12/23 10:38 p.m.

Haven't gotten to work on it much lately as I've been getting the open wheel ready for Temple Canyon next weekend but I just wanted to drop by and thank you all for the warm welcome! Again I will be updating periodically, just getting busy with racing season smiley

loosecannon
loosecannon SuperDork
5/12/23 11:03 p.m.

I like the ambition and vision of this project

78CobraII
78CobraII Reader
5/13/23 2:05 a.m.

Great project love the modular front uprights.

I saw a prototype named "Half11" on Hagerty in some coverage of a West coast LS Fest 2023.

 

TurboFource
TurboFource HalfDork
5/13/23 6:33 a.m.

Wow!!

Rigante
Rigante Reader
5/14/23 2:11 p.m.

Love this so much, I have similar plans, but with Audi v6 and slightly less mad bodywork, 

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