GRM Exclusive Reveal: Exocet Spec-A

v8exocet wrote:

ProDarwin wrote: I quickly plugged in some #s into a accel spreadsheet I had from powertrain class in college.... and using Saturn drag #s (likely a lot lower Cd (0.345), but bigger A (1.83sq m)), it shows a 1700lb w/ driver exocet with FMII turbo kit (this dyno: http://www.flyinmiata.com/tech/dyno_runs/1995_new_vs_old_FM_II.pdf) going 0-60 in 3.7 seconds, and doing the 1/4 mile in 11.4 @ 135.2 mph Obviously just a ballpark, but interesting. FWIW, the Saturn #s from school were about 0.8-1 second too slow, and about 5mph high on the trap speed. Not sure where the trap speed discrepancy comes from, but the time discrepancy is from the launch, as it basically calculates using a rolling start at 0.1kph, so power values are effectively 0 at that point (~11 rpm). Using a constant accel (spinning tires), or constant ~2000rpm power figure for the first .5-1 seconds (slipping clutch) would probably be a lot closer to reality.

so how about 1700lbs, 300hp, 225/50 15 slicks and 3.23s?

Its a more complex calculation than that.... got a dyno? Got a datalog of your max forward accel? What gear ratios in your transmission?

Grant,

Alternatively, you could, you know, have someone run it at the strip since it's already built and all...

So, when are you going to run it at the strip?

Warren v wrote: Grant, Alternatively, you could, you know, have someone run it at the strip since it's already built and all...

come get it and do it

ProDarwin wrote: Its a more complex calculation than that.... got a dyno? Got a datalog of your max forward accel? What gear ratios in your transmission?

i run a carbed small block ford. Im not that smart :P i leave that to warren

Warren - if you guys are looking to sell bodywork from your new '99 donor, I'm local and looking for parts!

nderwater wrote: Warren - if you guys are looking to sell bodywork from your new '99 donor, I'm local and looking for parts!

Donor (Kevin plasti-dipped the wheels black just to make fun of my car):

My DD:

I've got dibs on the driver's front quarter panel, the driver door is pending when I figure out whether or not I can replace my '01 door shell with a '99 shell without too much effort.

Our local Spec Miata buddies / Exocet Race builders have dibs on everything else. I'll let you know if they back out on the deal.

I'd be looking for the hood, front bumper and headlights. Thanks for keeping me in mind if they become available.

nderwater wrote: I'd be looking for the hood, front bumper and headlights. Thanks for keeping me in mind if they become available.

Headlights should be up for grabs. I'll message you when we work out the tub situation.

NA donor exocets are ending up weighing around what?

I know a guy with a NB built into sort of a DP car and he has taken 600lbs out of it

Jaynen wrote: NA donor exocets are ending up weighing around what? I know a guy with a NB built into sort of a DP car and he has taken 600lbs out of it

I think elsewhere it's been stated around ~1450ish?

Jaynen wrote: NA donor exocets are ending up weighing around what? I know a guy with a NB built into sort of a DP car and he has taken 600lbs out of it

1500 is a realistic number for using the stock Miata fuel tank and two seats. There are lighter Exocets out there, but I don't want to set unrealistic expectations. My NB weighs 2450, 600 lbs still only gets you to 1850lbs, and the new Exocet chassis is a lot more rigid than the braced NBs.

I had to register just to say how excited I am about this! I,d been tossing around the thought of a first gen Boxster with an LS swap... The Exocet is way more up my alley. I'm curious to some extent about titling? Obviously the sb100 thing has been beat to death. Still why not keep the miata title? An OBDI Miata as the donor, and swap whatever post 95 motor you want? I'm in cali, and have every intention of keeping it smogable, but it can't be impossible to do it that way can it?

Warren - Do you guys have any plans to build DBR1 chassis here, or just to import them? Do you think you'll do any of the frame analysis / modifications that you did for the Exocet?

I am in Cali as well and was pondering the same thing Osxuser.

Osxuser wrote: I had to register just to say how excited I am about this! I,d been tossing around the thought of a first gen Boxster with an LS swap... The Exocet is way more up my alley. I'm curious to some extent about titling? Obviously the sb100 thing has been beat to death. Still why not keep the miata title? An OBDI Miata as the donor, and swap whatever post 95 motor you want? I'm in cali, and have every intention of keeping it smogable, but it can't be impossible to do it that way can it?

While you retain the engine, transmission, diff, front subframe, rear subframe, and PPF brace, I would hesitate to call the finished product a Miata simply because you remove all of the unibody. We have had many customers call the PPF brace the "frame" and run it as a Miata, but we really like to tell people to take our MSO/MCO and register it as an assembled vehicle. From what we've been told, customers running their car as a Miata have not had issues with their insurance companies covering the car after the "modification", but I would really get something in writing that they will cover your liability if you stuff the car.

In Cali, you will need to retain every stock part of the emissions system. We have an '01 being built right now, and even the big '01+ EGR/charcoal canister system does fit underneath the rear tank cover. The huge stock airbox and filter system doesn't easily fit underneath the hood, so you'll pretty much need to find a CARB-exempt "cold air" intake. That state is annoying.

One of our customers invited the MX-5 Atlanta crew to help him build his Exocet (US #003) tonight. Check out his after-action report: http://www.mx5atlanta.com/forums/showthread.php?18328-Exocet&p=261218#post261218

From turbo Miata to Exocet roller in 4 hours. I knew the redesign would be a lot quicker to build than the UK version, but holy cow!

Meanwhile, the guys building #2 asked if we had a spare hood that they could use to mockup the engine bay. That car is the prototype for a Spec Exocet series, and they're keeping everything original Miata component under the hood (EGR, evap, charcoal filter, etc). We have an old set of mockup bodywork we made to test catalyzation ratios and our layup schedule, but it wouldn't fit in his Accord DD. Thankfully, Miata is always the answer:

So, now that the Exocet is taking off there should be some rust free shells sitting around for us northerners.

NA6R @ MX5Atlanta.com wrote: Last night was just under 4hrs. I think with 3-4 experienced wrenches and the right donor. A build could be running in under 8hrs. Maybe as little as 6.

The biggest thing keeping my dad and I from ever attempting a kit car project is the enormous time commitment required. In the Cobra replica community, it seems like most builds take at least a year of nights and weekends. But a few hours? Dude, that's AWESOME!!

DeadSkunk wrote: So, now that the Exocet is taking off there should be some rust free shells sitting around for us northerners.

Ill happily let you have the one off my NA when I do it but it will be on the west coast

nderwater wrote:

NA6R @ MX5Atlanta.com wrote: Last night was just under 4hrs. I think with 3-4 experienced wrenches and the right donor. A build could be running in under 8hrs. Maybe as little as 6.

The biggest thing keeping my dad and I from ever attempting a kit car project is the enormous time commitment required. In the Cobra replica community, it seems like most builds take at least a year of nights and weekends. But a few hours? Dude, that's AWESOME!!

I wouldn't BS you guys. All that's left on that car is reinstalling the Miata plumbing, reconnecting the harness, installing the seats, bolting in the gas tank, and slapping on the bodywork. So helpful when Mazda basically made the Miata out of Legos.

The UK builds averaged around 100-120 hours. The point they got last night is about the equivalent 40-50 hour point on a UK build. I think 8 hours is a stretch, but 10 might actually be possible if you know your way around a Miata. After seeing chassis #2 and 3 slap together so quickly, I'm confident in saying the majority of you guys could finish one (without Exocet experience) in well under 50 man-hours.

Sooooooo, I can just tow my Miata down to ATL on THursday, buy everyone a weekends worth of beer and pizza, and trailer it back to OK on Monday?

z31maniac wrote: Sooooooo, I can just tow my Miata down to ATL on THursday, buy everyone a weekends worth of beer and pizza, and trailer it back to OK on Monday?

I can't wait to get our new shop set up. We will offer a Local Motors-style "factory assembly" option, whereby you drive down your donor, strip it, split it on a two-post, and end up with a driveable roller. With at least one participant familiar with the process, it would be pretty easy to do that same-day.

The idea is to have them open to the public and build up pictures and video for a nice YouTube series of video instruction manuals.

Warren v wrote:

nderwater wrote:

NA6R @ MX5Atlanta.com wrote: Last night was just under 4hrs. I think with 3-4 experienced wrenches and the right donor. A build could be running in under 8hrs. Maybe as little as 6.

The biggest thing keeping my dad and I from ever attempting a kit car project is the enormous time commitment required. In the Cobra replica community, it seems like most builds take at least a year of nights and weekends. But a few hours? Dude, that's AWESOME!!

I wouldn't BS you guys. All that's left on that car is reinstalling the Miata plumbing, reconnecting the harness, installing the seats, bolting in the gas tank, and slapping on the bodywork. So helpful when Mazda basically made the Miata out of Legos. The UK builds averaged around 100-120 hours. The point they got last night is about the equivalent 40-50 hour point on a UK build. I think 8 hours is a stretch, but 10 might actually be possible if you know your way around a Miata. After seeing chassis #2 and 3 slap together so quickly, I'm confident in saying the majority of you guys could finish one (without Exocet experience) in well under 50 man-hours.

Wow, now I'm getting some serious interest as well.

Warren v wrote:

z31maniac wrote: Sooooooo, I can just tow my Miata down to ATL on THursday, buy everyone a weekends worth of beer and pizza, and trailer it back to OK on Monday?

I can't wait to get our new shop set up. We will offer a Local Motors-style "factory assembly" option, whereby you drive down your donor, strip it, split it on a two-post, and end up with a driveable roller. With at least one participant familiar with the process, it would be pretty easy to do that same-day. The idea is to have them open to the public and build up pictures and video for a nice YouTube series of video instruction manuals.

You keep making me more and more interested in building one of these cars.