Crusher
 

Some of you have already seen pics of our new enduro car. Just wanted to post a few more detailed pics for those that are interested.

The car is built specifically for the NASA 25 hours at Thunderhill Dec 3-4. It's an E2 car mapped from PTD. The VVT engine is purpose built, tuned exactly to the 148whp we are capped at for the class power to weight ratio.

The car's job is to gain the most track position for the least amount of fuel. Within that, the car must be able to run hard for 25 hours, at night, in the rain. It needs to be easy to diagnose and service. It needs to have the best possible safety equipment.

The car has no fuses or relays, instead relying on a solid state power switching unit, the Smartwire by Racepak. The fuse box you see in the engine bay is empty. Just an emergency spot to tap into hot leads in the engine bay should the need arise. The little box on the tunnel below the shifter is a Racepak USM (Universal Sensor Module) for our fuel level sender.
We were fiddling with the capacitor for the sequential COP conversion, hence the electrical tape (orange!) sliced open there. ESS Automatic fire system not completely installed in this photo.

More details on the build can be found on our blog; Behind the Wheel.

Center spot LED light bars not mounted in these pics

https://www.miataturbo.net/attachmen...ine=1320393096
https://www.miataturbo.net/attachmen...ine=1320393096
https://www.miataturbo.net/attachmen...ine=1320393096
https://www.miataturbo.net/attachmen...ine=1320393096

Car is a blast to drive. I'm glad to be part of the team!

Can't see pics.... :/

Its beautiful. Good luck with everything.

I wish I could do this!

Its kinda baller and I'm definitely getting a boner. Is it an actual NB2?

Effectively, yes. Rules allow swapping parts between NB1 and NB2 since they are both on the same line. You just have to replace whole assemblies like in SCCA solo. So this car has both NB1 and NB2 parts.

Fixed a bunch of stuff since you drove it. Misfire was bad cam angle sensor. New trans. Dash display all set up. Fuel gauge calibrated.
Bigger diameter steering wheel (350 from 330) gives a lot more leverage. New front subframe fixed alignment issue so we could raise it up to get proper bump travel and more camber. Yup, it's fun to drive!

it's missing something vital.

Beautiful car, Emilio. Your pictures show extreme attention to detail.

Are you running ABS?

I'm also really curious about your motor. Are you going to share your build plan at some point? I'm curious what made 148hp, and on what dyno... and what (if any) combinations you found made more power. I assume you probably don't want to give up certain info before the event, and that's cool too.

ABS for those 5am, rainy moments where slight of mind meets racecar driver.

Cool car, needs more orange though.

enduro car means inboard side mirrors. nice.

now about those aerodynamically-challenged 6UL wheels... time to make the 0CD (zero coeff of drag, not obsessive compulsive disorder) wheel design...

is this the vvt car you called me about? are dyno plots still top secret?

:brain:

That is the most simple engine bay i have seen in my entire life. looks like a dream to work on.

Yup, ABS. No brainer for the rain. Also reduces of driver error flat spots in the dry. About .5- .7 sec slower at sprint pace but we almost never need to push that hard in enduros. The abs can be toggled off by the driver and has a brake bias knob next to the radio (not in these pics).

NASA performance touring has two classing options. One which assess a points value for every modification with a 19pt cap to stay within a class. The second classing option allows builders to submit dyno sheets with actual whp and skip adding up points for each mod. When dyno classed, you have a nearly free reign for the engine as long as you stay under your self imposed whp cap. I can tell you that Crusher makes good torque with a broad powerband. Think WRC :)

We are not a big time pro team but our approach to the challenge of endurance racing is. Thus, we will keep some of the more innovative details of Crusher within the team until we have reached our racing goals.

Crusher is a bad bitch......Very nice indeed.
If I understood your wrc comment correctly than this thing probably has the best n/a miata torque curve imagineable

I have seen the dyno plot for this car.

I was impressed.

That's all I'm allowed to say. :D


And yeah, it is a very well put-together piece of machinery. This is the car I did some minor tweaking on the ECU of a few weeks ago, and even though it was still in pieces at the time (no doors / windshield / fenders / etc) you could really tell that all the folks who wrenched on it had done top-notch work. A lot of high-dollar race cars look great from 15 feet away, this one looks great up-close as well.

I heard it will make you rethink your entire exisitence.

Very nice, and you have my best wishes for competition!

Cool stuff!

What AFR's are you running?

I always thought modern day ABS was faster then not having ABS. Given that you guys have a brake bias valve so brake balance is not a issue, how does the ABS make you .5-.7 seconds slower?

What will happen to brake cooling?

I guess you should use VVT to limit topend power to the rules.

https://www.miataturbo.net/attachmen...ine=1320423462

I would be excited to see the dyno plot myself once made public. I have toyed with the idea of using a tuned N/A VVT motor in my Exocet, but will be going the way of a turbo motor.

It always makes me happy to see the attention to detail that seems to be put into this car. It makes me even happier to see it done by a group of guys that you know are doing it themselves to race against some of the factory backed teams. Kudos.

The solid state relay system makes me wet. Super impressive car.

Those must be some pretty dam bright LEDs to house them behind the lens... same ones you had mounted on the hood last year?

^ I believe they also mount a second pair of those LEDs in the bumper opening for a total of 4.

Correct.

Wow, that smartwire unit is really expensive. Unless someone uses all the channels it provides, it might be more economical to go with OTS solid state relays.

I will mount your bumper opening.

Yeah, this is what I was thinking. I guess we'll see eventually.

Very nice job Emilio.

Damn. Nicely done guys. I've always wanted an obnoxiously orange miata.

I need to change my pants now. Looks absolutely amazing Emilio! As always, best of luck out there!

Do it ******~! :jerkit:

that's the key. there is nothing modern about the ABS unit in Crusher. that is probably a 15 years old design at best.

12.8 through midrange, 13.0 on top. Cal is very finely tuned for economy.
Runs on CA91 pump gas.

The difference is that the Smartwire is fully programmable, values can be displayed on dash, logic circuits can be set up (turn off lights when cranking, turn off fuel pump if fire system triggers, etc). You want the defroster to trip the "fuse" at exactly 13.5amps? No problem. You want it to reset after exactly 4.5 seconds, you bet. You want it to attempt reset no more than 3 times, OK. You want to datalog all system voltages, amps, switch status, it'll do that too. Want to set a warning light on the IQ3 dash if the fuel pump draws more the 7.6 amps for more than 2.3 seconds, sure.

The stuff the Smartwire will do is endless. It ain't cheap but you are going into a cutting edge OEM realm of power control for even a home built project car.

What is the matting in the driver's footwell? I need to get some of that as a bare floor is so freakin' slippery in the wet!

Soooooo fired up to drive this car! Honored to be part of the the team with one of the BEST prepared enduro cars out there. I hope I can figure out what all those switches do... :)

Cheers,

Dean

What kind of EGT's you seeing at the end of the main straight?

Did you guys do anything like run the exhaust cam retarded to help control EGT?
Or use Inconel exhaust valves?

man that is a beast. What was done besides the intake to get the vvt to 148 whp. that seams like a very good power for a na bp motor.

high(er) comp pistons and tuning ? cams ?

that's a thermal mat. there are also some of that underneath the car also. but it also double as a friction pad.

you can get one of those stick on skateboard tape also.

What brand are you using? I've heat soak issues in the driver's footwell, not during track day sessions but on the multi-hour drive to/from the event.

The stuff in the floor is Koolmat. Still a bit slippery when wet but great in the dry.
The inside of the tunnel has Thermo-Tec adhesive backed barrier. Image here. Header and exhaust are wrapped to rear axle with DEI 2" header wrap. Car has almost no radiant heat inside. Putting a ton of thermal barriers on the cockpit side of the tunnel is a waste of time. Exhaust will heat all the sheet metal from the firewall to the rear bulkhead to 180° and radiate buckets of heat even if the little heel protector mat is saving your right foot. Keep the tub from getting hot in the first place and you don't need to go crazy in the interior.

We're honored to have you on the team Dean. For those of you who don't know who Dean is, he's one of the fastest Miata drivers in the country. There isn't anyone faster around Thunderhill IMO. I feel like we have a superteam with all the talent we have gathered.

Supertech SS valves and other measures. No EGT sensor which is an oversight on my part actually. We ran the motor ridiculously lean for quite a while in testing for. Oil, leakdown, compression and borescope all show no harm done. Experience has shown that our target AFR's are safe for a bone stock motor so we know we are good.

Stock junkyard USDM VVT motor will make 148whp with I/H/E and ECU on pump gas. JDM 10.5:1 motor with square top closer to 160whp with same bolt-ons.

What size wheels/tire widths?

I'm planning on going this type of NA next year before heading into the boosted world. Should be a nice jump up from a 94 ECU controlled 97 motor. Need to know if I should order some 15x8s or 15x9s, haha.

205/50 on 15x8's or 225/45 on 15x9's, depending on the event. Nothing unusual.

Curious why you have it running richer in the mid vs the top? I used to tune the higher RPMs 13.0 or slightly richer to help keep it cool, maybe I was doing it wrong? Anything below ~75 kpa I tuned it to 14.9 for more economy.

Because thats how N/A engines are tuned with it's VE peak somewhere in the midrange. You ran 14.9 at full load? That's deep into piston melting territory even N/A. We run a bit richer than 13.0 near the VE peak and close to 13.0 where it runs out of cam on top. Just back from full load, around 80kpa, we abruptly dial it back to 14.7 then leaner at very light load. Most of the fuel savings comes from carefully dialing in transient and closed throttle. We want as much torque as possible so we're not starving it for fuel where it wants it.

Thanks for clearing that up.

The 13.0 v 12.8 sounds about right, it sounds like it has a healthy "area under the curve." I simply always thought 13.2 was prime for N/A, so I always followed that, and tuned it richer in the higher RPM to keep it cool, even if it was losing power.

I tune 14.9 anything UNDER ~75 kpa (not sure where is best to transition, 70kpa or 80kpa)-- not at full throttle. I know the engine would be toast by now if I did lol.

Every motor is a bit different. Some might make peak power above or below 13.0. The rental motor we did two years ago made best power at 13.2 like you have observed. Much leaner than that on a stock long block is getting risky. For this tune, we played with AFR, spark, injection timing, VVT, exhaust cam timing to see where it made the most torque everywhere up to our 148whp limit.

A big part of this tune is track testing every tweak we do. Might look awesome on the dyno but drive like poo. We still have one or two more visits to our neighbors dyno so I can tune the map how I really want it.

Intentionally reducing engine VE by retarding the intake cam at all RPMs below 80 kPa can improve BSFC aka fuel economy because it reduces pumping losses.

Exactly. That's one of the reasons we chose to use a VVT engine.

Did you consider retarding the intake cam gear a tooth retarded from stock?

FWIW my car likes full retard by around 5800 RPM IIRC. At WOT / mid RPM it doesn't like even halfway to full advance. So if I jumped it a tooth I could get even more retard, and still have margin for full advance.

Perhaps the extra retard would further improve part-throttle BSFC.

Looking forward to the race. I'll be driving either a 2012 Grand AM Spec Civic Si or a RSX-S that was built for enduros. I'm not sure if our cars are E0 or E1, but either way we won't be racing you guys. So good luck in E2 and see you guys in a few weeks.

I had some advance headroom after I found peak torque below 5000 rpm. I bet there's enough to account for the extra tooth. I think I ended up at at about 36 or so crank degrees of advance from full retard to get max torque. that leaves another 10 or 15ish of additional advance. One tooth off is 15.6 degrees...

You two are both turbo right? I'm using all of the advance in one part of the map. Not sure how much I would benefit as it is already detuned on top. Andrew Kidd of TSE will be our head mechanic for T25. He also suggested the skip tooth.

Happy to hear the miss is all squared away. Best of luck. What a machine.

Yes I have a turbo, I don't know if y8s still does. (Wuss!) AFAIK he did his VVT tuning *with* the turbo.

All of the advance? That's pretty surprising.
Although a turbo motor would tend to want less advance.

Certain you didn't time the intake gear wrong?
Or set up the ECU wrong to that either
- you think you're at full advance but you're not
- you clipped the max advance in the setup, far from the VVT's actual max advance

Jason,

ECU and timing belt are correct. We are where we want to be. All of the advanced tuning ideas have been implemented. We're just fine tuning now.

of course i still have a turbo!

and I dont know that it affects how the vvt works all that much. it may change things a bit due to changes in charge density, but it's still very much tied to RPM and not so much to manifold pressure.

I need to do some more testing and tuning now that I have a better way to control it with the MS3.

Emilio, you're running all 48ish crank degrees of advance? Is it before 4500?

Y8s,

Shoot me an email for more info on the tune.

With my GT2560 I find that it wants less advance (less overlap) in the midrange, at 15 psi, than at 10 psi.

It stands to reason that as the limits of a turbo are reached, backpressure increases faster than manifold pressure, and thus it wants less overlap.

I see a re-route in use - you are using the BP26-10-271 head gasket? Did you open any additional passages through the gasket or leave it as is?

It's not charge density that wants to change VVT phase, it's the relative exhaust port backpressure (aka TIP, turbine inlet pressure) vs. manifold pressure.

ie the charge flow slows when TIP gets higher relative to MAP?