GRM Exclusive Reveal: Exocet Spec-A

z31maniac wrote:

Keith Tanner wrote: Yes, I read what you typed correctly. And I can see that the drawing shows a ridiculously low profile tire, meaning that you can't assume the same sidewall height as an "appropriately low profile tire". It's almost all wheel. Looks like Warren and I are on the same page here, my eyeball and his ruler are pretty close. A 19" wheel does not imply a 27" tire OD. Heck, I've seen Miatas with 18" wheels and approximately 24" tire OD. You're imagining a fairly high profile tire on that 19" of yours, the same sidewall found on a Miata with 14" wheels. In other words those are SUV sizes. Now, Warren's new renders, that shows a 15" wheel with 23" OD tires :) Which is how most Exocets will be fitted.

Is a 35 series considered low-profile? A 255/40/19 is 27.2, a 285/35/19 is similar as well. Either way, we continue to prove that everyone will argue anything on this forum with the goal of having the last word and being RIGHT!

35 is only part of the equation, of course. You can't really separate it from the section width. You're quoting SUV sizes. How about a 235/30-19 (24.6") Michelin Pilot, in stock at Tire Rack? And of course, the drawing was a fantasy render so why stick to actual available sizes. That drawing is running something like 255/5-27 tires.

I agree the "trunk" is challenging on an Exocet. It's there to hide the fuel tank, and, well, it looks as if it's there to hide something. If it was tied into the roll bar braces or somehow looking as if it were involved in the body instead of just dropped over top of something ugly, I think it would look more integrated. Look at the Atom "bodywork", all of the panels flow nicely into tubes.

Of course, with the design brief to make this bodywork backwards compatible, there are limitations as to what can be done. I know that new trunk is much more functional. The previous one didn't allow much in the way of options for fitting lights and the fuel tank filler was basically non-functional. This one's better on both counts.

Being in CA, a windscreen is a must for SB100. I see that the renderings have a windscreen, will this be part of the package?

kazoospec wrote: For what its worth, I really, really like the front end. Not sure the "trunk" is quite there for me yet. Looks a little like its tacked on as an afterthought. Its not horrible, just not quite there. I think its the slight rake up from the roll bar to the back end I don't like.

I'm with him. The nose is fantastic. The tail is dreadful. Just dump the whole thing and try again.

SB100 is an emissions waiver, nothing to do with windscreens. FYI. But one is under development.

I have to amend some of my comments about the tail. This one is better integrated into the framework than the old one was. It drops down below the level of the fuel tank "shelf". We'll see how it looks in person soon enough.

Javelin wrote:

kazoospec wrote: For what its worth, I really, really like the front end. Not sure the "trunk" is quite there for me yet. Looks a little like its tacked on as an afterthought. Its not horrible, just not quite there. I think its the slight rake up from the roll bar to the back end I don't like.

I'm with him. The nose is *fantastic*. The tail is dreadful. Just dump the whole thing and try again.

+1 Nose looks great. Tail section.....eh......

Yeah I think a more angular rear end with different taillights (that don't have the Harbor Freight trailer look) would be a big improvement.

I know you want to use taillights that are available off the shelf, but even a cluster of smaller lights (you want Euro-market-legal indicators and reverse lights too right?) would look way better.

You get to pick the lights you want, that's just what Warren stuck in the render. I wish he hadn't, it's caused an amazing amount of misdirection. And there's no way it would be legal as-is.

Here's what we'll be supplying. The outer ring is the taillight, and has a nice glow. The inner circle is a spectacularly bright turn/brake light, and the tail ring always lights up with it. For reverse, I'm going to tuck some lights in the angled section near the bottom of the tail panel.

Brakes and tails on.

Lights off. I haven't been able to get a picture of just the tails that represents them well.

Tallights are one of the most easily identifiable components of a car - and one of the most expensive to put into low volume production. So they're always going to look like they came from something else. 4" round and oval lights are widely available and inexpensive because they're a standard.

You could use beehive lights or tails like my old Land Rover. But then you'd get rear-ended, as they don't really light up well.

FWIW I like the tail. I would like it better if there were an indented cove in back that the lights and plate would fit into, but I bet molding it would be an issue. Having the cove would make it easy to black out that portion of the tail like an old musclecar. I just like the look.

I like the nose too but the lights up there by themselves still look silly to me. Are they there for regulatory reasons or just because thats where most people put them? I like XP3's headlights much better.

Junkyard_Dog wrote: FWIW I like the tail. I would like it better if there were an indented cove in back that the lights and plate would fit into, but I bet molding it would be an issue. Having the cove would make it easy to black out that portion of the tail like an old musclecar. I just like the look. I like the nose too but the lights up there by themselves still look silly to me. Are they there for regulatory reasons or just because thats where most people put them? I like XP3's headlights much better.

The headlights could look better if you used something like these: It would be more in the style of the body.

I definitely appreciate the effort to update the bodywork, but the render looks a little off to me. Possibly it's just the shading/quirks of the 3D modeling software.

I'm very much looking forward to seeing the first production set. This whole project has had me shopping for donor Miatas!

Hey guys, thanks for the feedback. We definitely weren't expecting so much focus on the rear taillights! Those are just render mockups.

The tail has large flat areas in the rear where the lights are mocked up. There is no frenching for indentation for the lights, so you can run anything you'd like. We'll offer a standard lighting package with a cluster of DOT-spec tail, brake, turn, and reverse lights, but one thing we've learned is that builders want freedom of choice. Locking you guys in to a particular taillight style wouldn't be as fun. Positioning can be done with a PDF template we'll provide. Flush-mounting is very easy, and you of course don't have to run those standard 4" round lights if you don't want to.

I'm away from my desktop, but the rear cover looks a bit more complete with the rear wing, fuel cap, and maybe possibly a secret rear double diffuser (you didn't hear that from me). You guys are right, there were a lot of constrains on that rear cover. It had to cover all the emissions crap from the '01+, a motorcycle battery, allow for proper fuel filler neck routing, have space for harness-bar-mount seatback braces, fit on the rear deck without trimming and within the constraints of the downtubes, allow for various types of rear license plates, allow a wide variety of lighting choices, generate zero lift if not downforce, reduce the trailing wake, and clean up the flow under the wing. The biggest constraint: it had to be a single-piece mold. That's right, that rear cover actually has healthy draft angles. Any undercuts would increase the cost of the kit by at least $500 due to extra tooling, maintanence, post-mold sanding and polishing, and a longer layup process. Every part of the new bodywork is single-piece, keeping with the project mission of low cost without sacrificing quality.

Another fun fact: every surface you see except for the (bolt frenches on the cowl) is single curvature, which means you could form each surface's shape with a sheet of paper. This will let me cheaply CNC-cut the plugs without requiring the use of a CNC-router. I'll explain later, but it's basically all a giant origami structure. I haven't seen this particular method done before, but if it works half as well as the Exocet's self-fixturing, it'll be pretty fun. Doing this the lazy way (5-axis CNC router) would cost us about $40k-60k and would require the kits to go up to around $10k.

My workstation is making a spinny video for you guys to show off the rear. The whole design went through many iterations and was reviewed by many designers. The "boxy" comments were made by the designers I worked with until they saw the live 3D model. There's more shape in there than you realize, and it really looks complete with a rear wing.

22 actually before you account for putting a 195/45 16 on an 8 inch wide wheel

Keith Tanner wrote: They're not 19". Given that they're level with the top of the main tube, that means they have to be closer to 28" in diameter. Compare to this - the tire is about 23" in diameter. I think there were some issues with this not actually being possible to produce. Or, at least, in an affordable way. There's a lot more to designing a body than simply trying to draw the Lost Transformer. How would those panels come out of a mould?

I like the new bodywork. When will the transition to the new bodywork happen? I'm especially interested in the wider fenders since I think 225s will probably be a better size for a supercharged track car with downforce.

All new orders will be for the 2014 bodywork, and we are working everything out for those on the waiting list.

I actually recommend 205-width tires on 8" low-offset wheels. 225s are slower unless you bring the pressure down to the low teens, and then they're not as responsive. We went back-to-back at Atlanta Motorsports Park where one of our customers was running 225s with a turbo. We dropped XP-3 down to 205s, and it felt a lot better. XP-3 is putting down 252whp, which is more than you want to go with a supercharged motor with stock internals. When the entire car is 1500 lbs, 205 is plenty of tire, especially when it's cooled by a bunch of airflow.

We can't stop customers from running wider tires, but I'll say 205 is the sweet spot until you add the weight of a v8.

The only tire I would run in 225 is an A6 or true racing slicks. 225A6 will be the autocross setup to beat.

Warren v wrote: I actually recommend 205-width tires on 8" low-offset wheels. 225s are slower ...

That makes sense. We'll probably be on Goodrich g-Force R1 or A6s so the 225 width might be right.

We have another datapoint for weight and balance! We got XP-3's numbers while it was facing down a hill at VIR, so we suspected they were a little nose-heavy.

Here's one of the prototypes with a similar loadout to XP-3. The prototype frames were around 220 lbs, while the production cars (like XP-3) are 190±2 with powdercoat. Most of that extra weight is in the firewall, too, so production cars will be a little less front-heavy. This car has a 2560R turbo, intercooler, and exhaust that ends before the diff. A naturally-aspirated car would have ~40lbs less weight on the front tires and more weight on the rears with a muffler. This is with a full tank of gas, and the seats are set for a driver around 5'10" (forgive me David if I'm wrong on the height). I like to sit about 2-3" more rearward.

Uninhabited

1548 lbs, F: 54.8%

Don't take that front % to heart, as it's such a light car that empty distribution is meaningless. Most drivers will be >10% of the car's overall weight.

With a 175 lb driver:

1725 lbs , F: 52.6%

With 300lbs of driver/passenger:

1850 lbs, F: 52.2%

Forgive the cross weight wonkiness, this is not on a perfectly level floor and the perches haven't been leveled.

For the inevitable toilet-seat-racers out there, 52% F is plenty balanced, especially for Miata geometry. Miata's ain't 50/50; check the bottom of this spec sheet if you don't believe me:

I found a must have Exocet accessory at the store today:

Your must have accessory shows up as two black lines, with white in between...

Warren, how is it loading onto a trailer with that front wing? My trailer has drop axles so it is pretty low, but not that low. Any chance making that front wing assembly removable with spring loaded pins or something like that? Otherwise, I assume it means paying the ransom for those plastic Race Ramps. Your car has intercooler plumbing to deal with, mine would not. Either way it is what it is but making the loading / unloading process easier would be a nice plus.

Jim

XP-3 had maybe an inch of ground clearance when that picture was taken. With the recommended racing ride height (4" clearance), the lowest part of the wing mount is 4.4" off the ground and 32" in front of the tire. The approach angle is 7.8°. That said, the wing mounts are well inside where your ramps would be. That's how we loaded it, the wing dips a little under the ramps until the car pitches up. Street ride height will give you an inch more clearance.

TLDR: I designed them to hit at a greater angle than you would center-hang the car. If the trailer is level to the ground, that is.

Perfect.

Kevin asked me to tell you guys to be patient if you're waiting to hear back from Info@Exomotive.com. He's been utterly swarmed with inquiries and phone calls, especially since the bodywork release.

I made a spinny for you guys: http://www.youtube.com/watch?v=xHGFJ7Cy5MI

Warren v wrote: I made a spinny for you guys: http://www.youtube.com/watch?v=xHGFJ7Cy5MI

The back end looks a lot better with the wing.

Man I need to finish up some projects to get to this...

Warren, did I see where you were working on a tool for playing with color combos or was that for internal use only? (buying signal)