Intro and some questions.

[Jungle Gym]

I haven't bought a kit yet, but I wanted to share some Utah DMV info and links over in that section so that viewers don't have to go dig through UDMV's website for it. So I registered, posted and figured I'd introduce myself and ask some questions.

I'm in South Ogden, UT and have been turning wrenches either professionally or recreationally for almost 28 years. I used to be really into cars, but when I moved here ten years ago, I discovered off roading and sport bikes and my interests shifted. I still love off roading, but the interest in bikes is waning and feel that a Goblin will fill that gap (and that space in the garage) quite nicely. I was doing some daydream math about power and torque to weight ratios and all- up costs, and I'm figuring that a turbo Goblin with 325ish WHP will have similar acceleration performance as a new high end 1000cc sport bike and will cost a little less. Full disclosure: I fully intend to buy one of these for a winter project and have it on the road next spring. I've been around the internet long enough to know that everyone talks big and I always roll my eyes when someone's first post talks about turbo this and that, so we can talk more about that when the parts start rolling in this winter.

So in the mean time, I hope to have some answers to my questions and will otherwise sit back and quietly enjoy all your build threads.

• What is done for a parking brake? Most states will require this to pass inspection. Since the Cobalt front brakes are now the rears, they provide no provisions for a parking brake.
  
• How did you arrive at the tire size combos you mention? I ask because I was looking on Tire Rack's site and it's very difficult to impossible to find matched tires in the size combos you recommend in something other than a slick or a 100 treadwear gumball. Since tire size is somewhat fluid, what treadwear rating would you recommend for the street? As this thing weighs half of anything I've ever owned, my experience with what lasts for how long goes out the window. Would a 100 treadwear give decent life? Would something with a 280 treadwear be too hard?
  
• Have you attached an accelerometer to the car to get a rough idea of the cornering forces it's able to generate?
  
• What initial alignment settings, ride height and tire pressures do you recommend?
  
• What sort of intercooling solution do you have for the turbo engines? I'm assuming it's going to be a water to air unit with the heat exchanger somewhere on the side behind the passenger space?
  
• Can there be a reduction in cost if a component such as the exhaust or brake rotors isn't needed?
  
• What brakes are used for the rear- the stock Cobalt fronts?
  
• What's the most power you've put down with this car so far? What's the limit; is my daydream of 325 WHP going to just end in uncontrollable wheel spin, or can this car handle more?
  
• Can the fenders be ordered wider to fit over wider tires?
  
• Are you willing add small things at the customers request like, say, a bar to mount shoulder belts to so that a five point harness may be used?
  
• I would really like more pictures of the car in various stages of completion, but I know you're very busy so I'll wait patiently for the build threads to provide those.

I'm sure I'll have more questions down the road. I appreciate your time and all the work you're putting in to this. I look forward to my build!

 

[Adam]

• Hey Jungle Gym. Thanks for joining and sharing so much information. Here are answers to some of your questions:
  
  • What is done for a parking brake?.
  
  We are going to be adding a spot brake to both rear rotors that will be cable operated.
  
  • How did you arrive at the tire size combos you mention? Would a 100 treadwear give decent life? Would something with a 280 treadwear be too hard?
  We picked tire sizes close to the Ariel Atom 3 sizes (205/50-15, 225/45-16). We have just a little bit more rear weight than the Atom so we went with a slightly smaller front (195/50-15) to give a good front to rear balance but you could run the Atom sizes if you want. For the track, we are going to run the 205/50-15 front and 245/45-16 rear.
  
  For the SS, it is a little harder because of the lug pattern. It is hard to find 15 inch wheels so we are running 16 front and 17 rear with 205/45-16 and 245/40-17.
  
  One thing I've run into on TireRack is that when I put in both sizes of tires, it sometimes doesn't show all possible matches. For example, consider the combo of 195/50-15 and 225/45-16. I know this combo exists on TireRack because we bought these. However, when you search for both tires together, you end up with no results:
  
  
  
  If I don't search as a combo, I can see that the Dunlop Direzza ZII Star Spec is available in both sizes:
  
  
  
  The same is true for the Potenza RE-71R, the Toyo Proxes R1R and more. Search for the smaller tire size (195/50-15 or 205/50-15), select a tire and see if it has the larger size available as well. Until their search is fixed, you'll have to work to find tires.
  
  I would stick to 200 treadwear. It is grippy without wearing too quickly on such a light car.
  
  • What sort of intercooling solution do you have for the turbo engines? I'm assuming it's going to be a water to air unit with the heat exchanger somewhere on the side behind the passenger space?
  
  We do plan to run water to air cooling for boosted cars. We want to install a heat exchanger at the front. It will collect fresh air through ducts near the control arms so that it doesn't use the air from the radiator. Just like with the suspension settings, this is something we are going to experiment with.
  
  • Can there be a reduction in cost if a component such as the exhaust or brake rotors isn't needed?
  
  That could be possible.
  
  • What brakes are used for the rear- the stock Cobalt fronts?
  The stock front calipers and rotors from the 4 lug Cobalt are used for the rear brakes. We redrill the rotors for people with the 5 lug pattern. The front brakes are the base calipers and rotors from the 5 lug Cobalt: 11 inch rotor, extended caliper bracket. This combo makes the fronts lock up just before the rears (which is much safer than the other way around). We are happy with how the brakes have worked out.
  
  • What's the most power you've put down with this car so far? What's the limit; is my daydream of 325 WHP going to just end in uncontrollable wheel spin, or can this car handle more?
  
  The most power is from our supercharged P2. It is probably around or just over 200hp. You have to act like a bonehead to get the tires to spin, even with the old tires we have on it. Dumping the clutch with the engine revved up is the only way to spin them.
  
  We are going to try to get our SS turbo car going soon so that we can see how that works out.
  
  • Can the fenders be ordered wider to fit over wider tires?
  
  We are going to be making some wider fenders but we probably aren't going to support much wider than 245.
  
  • Are you willing add small things at the customers request like, say, a bar to mount shoulder belts to so that a five point harness may be used?
  
  All Goblins have a shoulder bar at the right height for mounting shoulder belts (for an averaged sized seat). There is also a tab for mounting the anti-submarine strap

 

[Jungle Gym]

Adam, thank you for taking the time to answer my questions so quickly. I've spent some time on the Tire Rack website and it is somewhat tiresome to navigate. Thank you for the screen grabs as well; when the time comes, they will be very helpful. I'm looking forward to further developments!